REVIEWAND PERSPECTIVES

Mesenchymal tumours of the mediastinumpart II

Michael A. den Bakker1,2 & Alexander Marx3 & Kiyoshi Mukai4 & Philipp Strbel5

Received: 24 June 2015 /Revised: 6 August 2015 /Accepted: 11 August 2015# The Author(s) 2015. This article is published with open access at Springerlink.com

Abstract This is the second part of a two-part review on softtissue tumours whichmay be encountered in the mediastinum.This review is based on the 2013 WHO classification of softtissue tumours and the 2015WHO classification of tumours ofthe lung, pleura, thymus and heart and provides an updatedoverview of mesenchymal tumours that have been reported inthe mediastinum.

Keywords Mediastinum .Mesenchymal tumours .Soft tissuetumours

Introduction

In this second part of a two-part review, the 2013 WHO clas-sification of soft tissue tumours and the 2015 WHO classifi-cation of tumours of the thymus form the basis to summarizecurrent knowledge about soft tissue tumours in the mediasti-num. This comprehensive review covers published reportsfrom the English and Japanese literature. In the first of thesereviews, general aspects, adipocytic, fibroblastic/

myofibroblastic, fibrohistiocytic tumours and soft tissue tu-mours arising as somatic components in germ cell tumours,were discussed. We now turn to mediastinal smooth muscle,skeletal muscle, vascular, chondro-osseous, nerve sheath andmiscellaneous tumours of uncertain differentiation, includingundifferentiated sarcomas. Since most of the tumours de-scribed here closely resemble soft tissue tumours elsewherein the body, we will focus our review on defining criteria,epidemiology, clinical findings and prognosis, rather than his-tological descriptions. For in-depth coverage of the histologi-cal aspects of these tumours, the reader is referred to specificliterature.

Smooth muscle tumours

Smooth muscle cell tumours resemble normal smooth muscleand retain many of their immunohistochemical markers. Few-er benign smooth muscle cell tumours (leiomyomas) than ma-lignant smooth muscle tumours (leiomyosarcomas) have beenreported in the mediastinum.

To qualify as a primary mediastinal leiomyoma, tumoursshould arise from the somatic soft tissue of the mediastinum,whilst esophageal and large vessel primaries should be ex-cluded. If these criteria are applied, primary mediastinalleiomyoma is very rare with approximately 20 reported casesin the literature [14, 19, 136, 139, 149, 162, 180, 205, 227].Mediastinal leiomyoma is twice as common in females as inmales and is mainly seen in the posterior mediastinum of olderadults (age range 2375 years; median age 50 years). Thesetumours may remain asymptomatic, or patients may complainof dyspnea or chest pain. The tumours may grow to a largesize (up to 1,600 g). The morphology of mediastinalleiomyoma is similar to its counterparts elsewhere in the bodyand is defined as a neoplasm resembling normal smooth mus-cle cells and devoid of pleomorphism and necrosis and with a

* Michael A. den Bakkerbakkerma@maasstadziekenhuis.nl

1 Department of Pathology, Maasstad Ziekenhuis, PO Box 9100,3007, AC Rotterdam, The Netherlands

2 Department of Pathology, ErasmusMC, Rotterdam, The Netherlands3 Institute of Pathology, University Medical Center Mannheim,

University of Heidelberg, Heidelberg, Germany4 Department of Diagnostic Pathology, Saiseikai Central Hospital,

Tokyo, Japan5 Department of Pathology, Universittsmedizin Gttingen,

Gttingen, Germany

Virchows ArchDOI 10.1007/s00428-015-1832-6

very low mitotic rate (

The differential diagnosis of the rare primary mediastinalrhabdomyosarcoma is the much more common rhabdomyo-sarcoma as a component of a germ cell tumour [23, 35, 69,120]. In germ cell tumours with somatic-type malignancy, theprognosis is determined by the somatic (i.e. sarcomatous)component and in the setting of rhabdomyosarcoma is dismal.Rhabdomyoblastic differentiation has been reported in bothlow-grade (thymoma) [29, 129, 174] and high-grade (thymiccarcinoma, carcinosarcoma) [41, 48, 145] thymic epithelialtumours and thus enters the differential diagnosis of rhabdo-myosarcoma [29, 41, 48, 129, 145, 174]. Identification of anepithelial component by appropriate immunohistochemicalstaining will aid the accurate diagnosis. Rhabdomyoblasticdifferentiation may also occur in MPNST, which are thencalled malignant Triton tumours. Nine cases have been report-ed in the mediastinum (reviewed by Ren et al. [166]). Thetypical spindle cell MPSNTcomponent usually predominates,whilst cells with rhabdomyoblastic differentiation commonlyform a minor component of the tumour. These tumours carry avery poor prognosis.

Vascular tumours

Amongst mesenchymal neoplasms in the mediastinum, vas-cular (endothelial) tumours are not uncommon with well over100 cases reported in the literature.

Benign and intermediate-grade vascular tumours

Benign blood vessel tumours (hemangioma variants) havebeen reported as individual cases and have been summarizedin several reviews [32, 39, 127, 130]. Endothelial tumours ofintermediate grade (hemangioendotheliomas) are character-ized by local infiltrative growth and rare metastases.

Mediastinal hemangiomamay originate in the soft tissue ofthe mediastinum or may arise in the thymus [5, 32, 154].Mediastinal hemangiomas span a wide age range, from thenewborn to the elderly, with most cases occurring in youngadults. Of the reported cases, 5075 % were located in theanterior mediastinum [32, 130]. Up to 50 % of cases wereasymptomatic. Patients with symptomatic tumours presentedwith pain, cough and rarely with signs of compression of vitalstructures by the tumour, such as Horners syndrome, neuro-logical signs and superior vena cava obstruction [32]. Tumoursize ranged from a few centimetres to 20 cm [32, 130] andincluded both capillary and cavernous hemangioma subtypes.In the series by Moran and Suster, associated histological fea-tures included fatty metaplasia, fibrosis, smooth muscle over-growth and inflammation [130]. Surgical resection is curativein most cases, although recurrence may rarely occur [32].

Lymphangioma has been reported as a cystic mass in themediastinum of children and is very uncommon in adults

(Fig. 1) [61, 147, 156]. Lymphangiomas are not considered trueneoplasms but rather malformations of the lymphatic vasculaturewith progressive cystic change resulting from obstruction of lym-phatic drainage [80]. The progressive growth of these lesionscauses dyspnea. Surgical resection is curative in most cases, al-though recurrences may require repeated surgery [156].

Vascular endothelial tumours of intermediate malignancy(with local aggressive behaviour and/or rare metastases) havebeen reported in the mediastinum as case reports and caseseries. These include kaposiform hemangioendothelioma(KHE) and a single case of composite hemangioendothelioma[24].

Less than 15 cases of exclusively mediastinal KHE havebeen reported, in addition to a number of cases where largeKHEs extended contiguously from the neck into the medias-tinum [51, 77, 81, 89, 114, 140, 210, 211, 220, 226, 234]. Thereported mediastinal KHE cases were exclusively seen in in-fants (016 months of age) with almost equal sex distribution.Thrombocytopenic consumptive coagulopathy (Kasabach-Merritt syndrome) was present in almost all of the reportedcases and is a major cause of fatality in this tumour. Medias-tinal KHE is histologically similar to its soft tissue counter-parts and is characterized by poorly circumscribed nodules oftightly packed small capillary-sized vessels, Kaposi sarcoma-like areas with spindled cells and absence of HHV-8 immuno-reactivity. A component of larger lymphatic vessels is oftenpresent. The prognosis of KHE is variable. Complete surgicalremoval may provide a cure but may not be possible in caseswith extensive infiltration. Variable success has been achievedby medical treatment with interferon and chemotherapy. Theprognosis is often determined by the haematological compli-cations rather than the local tumour effects. In the mediastinalcases with follow-up information, six patients were alive with-out evidence of disease, two patients were alive with diseaseand two patients died of disease.

A single case of composite hemangioendothelioma, a rarevascular neoplasm of intermediate grade with variable histo-logical components, was described in the central mediastinalarea of a 50-year-old female. There was evidence of disease13 months after surgical resection [24].

Malignant vascular tumours

Malignant vascular tumours comprising epithelioidhemangioendothelioma (EHE) and angiosarcoma (AS) havebeen reported in the mediastinum.

Mediastinal EHE is a malignant endothelial neoplasm withapproximately 30 cases published mostly as case reports [7, 16,25, 27, 56, 60, 88, 103, 109, 115, 121, 143, 151, 191, 202, 215,216, 229] and a single series of 12 primary mediastinal casesdescribed by Suster et al. [191] All cases occurred in adults(median age 46 years, age range 1969 years) with twice asmany cases reported in males as in females. A considerable

Virchows Arch

proportion of EHE was discovered incidentally on imagingstudies for other indications. Symptomatic patients complainedof chest pain, cough and dyspnea. All reported cases were lo-cated in the anterior or anteriorsuperior mediastinum and anumber of reports document involvement of or an origin fromlarge veins (superior vena cava and innominate vein in partic-ular). The tumours were often partially encapsulated but oftenat least focally contained infiltrative areas. Mediastinal EHEshowed the typical histology with epithelioid endothelial cells,often with intra-cytoplasmic lumina (blister cells), set in avariable hyalinizedmyxo-collagenous or chondroidmatrix. Os-teoclastic giant cells and metaplastic bone were reported inseveral cases [191]. Intra-nuclear cytoplasmic inclusions areanother feature typically observed in EHE. A recurrent geneticaberration in EHE, including mediastinal cases, is translocationof the CAMTA1 gene on chromosome 1p and fusion with theWWTR1 gene on chromosome 3q [7, 53]. A subset of EHEharbour a different genetic abnormality in which a YAP1-TFE3 fusion gene is generated from YAP1 sequences on chro-mosome 11 and TFE1 sequences from the X-chromosome [9].To date, the YAP1-TFE3 fusion gene has not been reported inmediastinal EHE.

The differential diagnosis of EHE includes epithelioidangiosarcoma (EAS) and metastatic adenocarcinoma. Theintra-cytoplasmic lumina in EHE may easily be mistaken forglandular differentiation, which in conjunction with thecytokeratin expression seen in up to 40 % of EHE may leadto an erroneous diagnosis of metastatic carcinoma. The diag-nosis of EHE can be established by recognition of the vascular

differentiation by immunohistochemistry (with CD31, CD34,ERG or FLI staining) (Fig. 2).

Epithelioid angiosarcoma shows high-grade cytologyand usually lacks the typical myxoid, hyaline or chondroidstroma of EHE. Features more commonly associated withEAS include capillary vessels, vascular lakes and papillarygrowth [7]. The genetic changes identified in the EHEhave only been identified in a single case of EAS andthus may serve to distinguish the two entities. The prog-nosis of mediastinal EHE is not unfavourable; of the 15cases with follow-up, 13 patients showed no evidence ofdisease following surgical removal, one patient died ofcomplications of the surgical procedure, and one patientdied of the tumour 9 years after initial presentation (nosurgery was performed). A subdivision into low- and high-grade EHE on the basis of cytonuclear features has beensuggested [7].

Mediastinal AS has almost exclusively been reported inthe anterior mediastinum. Less than 40 cases are on record[7, 42, 67, 69, 93, 151, 195, 217, 230]. Although olderreports frequently described a favourable outcome evenafter marginal resection, it should be noted that many ofthese did not include immunohistochemical confirmation,raising the possibility that the reports may have incorpo-rated entities that would currently not be diagnosed as AS.Furthermore, the prognosis and the demographics of thepatients in older series are in marked contrast with morerecently described cases. In a recent series of mediastinalEAS, 12 of 13 patients succumbed to the disease [7], whilst

Fig. 1 Lymphangioma. Anteriormediastinal mass considered to bea benign cystic lesion wasdiscovered during routine check-up in an 81-year-old male. Themass increased in size from 16 to22 mm in a period of 8 years. Norecurrence 1 year after thesurgery. aNon-enhanced CTaxialimage shows a smallhomogeneous mass withattenuation. b Axial fat-saturatedT2-weighted MR image shows ahyperintense signal with smallinternal septations. c HE stain ofresected tumour. Irregular thin-walled vascular structures inadipose tissue. d D2-40 stain,supporting the lymphaticdifferentiation of the liningendothelium

Virchows Arch

in older reports with follow-up data, no evidence of diseasewas documented in seven of ten patients after surgical remov-al (follow-up 636 months) [42, 67, 69, 93, 195, 217]. Simi-larly, in a more recent series, there was a distinct male pre-dominance with a median age of 67.5 years, whilst in the olderreports, an equal gender distribution with a median age of42 years was recorded. The demographic and prognostic dataof the recent series are more concordant with the high tumour-related mortality reported for AS in other organs [57]. In con-trast to EHE, all cases of AS were symptomatic with painbeing the most common presenting symptom. Most AS mea-sured less than 10 cm in largest dimension and showed aninfiltrative growth pattern. There are too few well-documented cases to draw firm conclusions on treatmentand prognosis. The main differential diagnoses are other vas-cular neoplasms, in particular EHE. However, AS is an infil-trative neoplasm with high-grade cytology and usually lacksthe peculiar fibro-myxoid stroma of EHE. It is not uncommonto observe AS as a component of somatic type malignancy in

mediastinal germ cell tumours [35, 47, 69, 120, 131, 171,230].

Chondro-osseous tumours

To qualify as a primarymediastinal osteo- or chondrosarcoma,an origin from bony structures, chest wall soft tissue, tracheo-bronchial structures and a putative relationship with a germcell tumour must be excluded. Bearing these restrictions inmind, about ten cases of primary extraskeletal mediastinalosteosarcoma cases occurring in all compartments of the me-diastinum have been reported [28, 70, 84, 86, 110, 186, 196,208, 221]. However, similar to neoplasms described in previ-ous paragraphs, several reports predate current concepts andideally would require substantiation. Although reported casesspanned a wide age range (1977 years), six cases occurred inyoung adults (1930 years). Four patients were females, andsix were males. A single case was most likely a radiation

Fig. 2 Epithelioid hemangioendothelioma. Anterior mediastinal mass in56-year-old female. Angiosarcoma was diagnosed on needle biopsy. Thetumour was subsequently excised and diagnosed as epithelioidhemangioendothelioma. The presence of a CAMTA1-WWTR1translocation was confirmed by RT-PCR. The patient remains free of

recurrence 23 years post-surgery. a The HE stain shows myxo-collagenous matrix with epithelioid cells with intra-cytoplasmicvascular spaces consistent with so-called blister cells. b MembranousCD31 staining confirming the vascular nature of the tumour cells

Fig. 3 Ganglioneuroma. Paraspinal tumour in the mediastinum of a 45-year-old female, extending from the cervical region to the diaphragm. Themass was excised, the patient remained disease free. a CT image showing

the cervical aspect of the paraspinal mass. b HE stain of the tumour,revealing a schwannian background with scattered ganglion cells. cNeurofilament stain revealing elongated slender cytoplasmic extensions

Virchows Arch

induced osteosarcoma following radiotherapy for Hodgkinsdisease [28]. Most patients presented with chest pain or dys-pnea. Synchronous secondary deposits were reported in sev-eral cases [110, 186, 196, 221]. Tumours ranged in size from4.5 to 16 cm and were often partially encapsulated. Of eightpatients with follow-up data, five died of disease, one patientwas alive with disease and two patients showed no evidenceof disease after therapy, including one patient who developeda recurrence, which was treated with radiotherapy. Osteosar-coma has only rarely been reported as somatic type malignan-cy in germ cell tumours [131, 204].

Less than ten cases of extraskeletal mediastinalchondrosarcoma have been reported, six cases were describedin a single series [189] and the remaining cases as case reports.Tumour location in the anterior as well as in the posteriormediastinum was described for both conventional and mesen-chymal chondrosarcomas. Patients ranged from 11 to 36 yearswith no obvious sex predilection [91, 189]. Tumours ranged insize from 5 to 15 cm and were mostly encapsulated. Themesenchymal chondrosarcomas contained areas of primitivesmall cells and more mature cartilaginous areas, whilst theconventional chondrosarcomas were composed of hyalinecartilage with increased cellularity and atypical chondrocytes.In the cases with follow-up, recurrences occurred in five pa-tients, two patients died of disease (one after a recurrence) andtwo patients were alive without disease (one after a recur-rence). Chondrosarcoma arising in a germ cell tumour appearsto be extremely uncommon with only a single reported case inthe mediastinum [125].

The histological differential diagnosis of mediastinal oste-osarcoma and chondrosarcoma is very limited. Osseous meta-plasia may occur in other tumours including thymoma [183]but is unlikely to be confused with the atypical cells of oste-osarcoma. Bone or cartilage tissue of variable maturity may bea component of a mediastinal teratoma but does also not showthe irregular texture and cellular atypia of osteo- andchondrosarcomas. Osteosarcomatous differentiation has alsobeen reported in malignant peripheral nerve sheath tumours[44].

Ewing sarcoma/primitive neuroectodermal tumour(PNET)

In the WHO classification, Ewing sarcoma (ES)/PNET is in-cluded in the classification of bone tumours despite the factthat up to 20% of cases are extraskeletal (extra-osseous Ewingsarcoma, eES) and are located in various soft tissue sites andeven in parenchymal organs. Furthermore, the cell of originand differentiation of ES/PNET remain currently unknown.As stated above for chondro-osseous tumours, an origin frombony structures such as vertebrae and chest wall must be ex-cluded in order to qualify as primary mediastinal eES/PNET,leading to the exclusion of several reported cases where

tumours extended to these structures or where insufficientdetails were given [112, 231]. Less than 20 convincing casesof eES/PNET have been reported in the mediastinum [3, 50,74, 75, 100, 102, 119, 153, 164, 169, 178, 231]. The casesmostly occurred in young individuals (median age 28 years,range 566 years) with equal gender distribution and in allcompartments of the mediastinum. The presenting symptomswere non-specific; pain and dyspnea were frequent. Sometumours extended through the foramina and caused nervecompression symptoms [100, 119, 169]. The characteristicgenetic translocation involving the EWSR1 gene on chromo-some 22was confirmed in several cases [75, 119].Multimodaltherapy was given in a number of cases with variable results.Long-term cure was achieved in isolated cases.

The differential diagnosis is broad and includes eES/PNET with variant translocations and eES-like tumours un-related to EWS (small blue round cell tumours), as well assynovial sarcomas and undifferentiated pleomorphic sarco-mas with a small cell morphology. In the anterior medias-tinum, T lymphoblastic lymphoma (TLBL) is a major dif-ferential diagnostic consideration, especially since both tu-mours express CD99. Immunohistochemical staining forlymphocyte markers and TdT will exclude lymphoma.Small cell neuroendocrine carcinoma (both primary medi-astinal and metastatic) can be excluded by its high-gradecytologic features and expression of neuroendocrine and(sometimes weak) epithelial markers and TTF1. In the pos-terior mediastinum, neuroblastoma must be excluded,which is usually CD99 negative and does not show EWSR1gene translocations.

Nerve sheath tumours and tumours derivedfrom the autonomic nervous system

Neural tumours are the most common mesenchymal tumoursin the mediastinumwith an estimated incidence of 1219% ofall mediastinal tumours. Aspects of these tumours have beenthe subject of several comprehensive reviews [65, 116, 122,165, 167]; the various entities will therefore only be coveredin general terms in this review, for specific details the reader isreferred to these reviews. Neural mediastinal tumours may becategorized into tumours of nerve sheathschwannian deri-vation, which are predominantly seen in adults and those ofthe autonomic (neuronalganglionic/sympatheticparasym-pathetic) nervous system, which are much more common inthe paediatric age group. Tumours which are thought to ariseform embryonic remnants of the neural tube, such as rareexamples of ependymoma (Table 1), constitute a third catego-ry [43, 54, 222].

Schwannomas are the most common of the mediastinalneural tumours and are considered to arise from spinalnerves. They are therefore mainly seen in the posterior

Virchows Arch

mediastinum, although cases located in the anterior medi-astinum are also on record [193, 206]. A significant pro-portion of cases are asymptomatic and discovered inciden-tally by routine imaging investigations. Symptomatic casespresent with chest pain, cough or compression symptoms,in particular in tumours extending through spinal foramina.There is no gender predilection for schwannoma; they aremost common in young- to middle-aged adults. Similar toother locations, these are circumscribed encapsulated tu-mours, which may undergo cystic degeneration and degen-erative (ancient) changes. Surgical removal is curativewith extremely low recurrence rates.

The cellular variant of schwannoma, which may be mistak-en for a malignant tumour owing to its increased cellularityand lack of Verocay bodies, is particularly common in themediastinum. Its benign behaviour has been confirmed in sev-eral series [58, 113, 218, 223]. A more aggressive variant ofschwannoma, previously designated melanotic schwannoma,has been shown to have a high recurrence and metastatic ratewith associated 27 % mortality in a single series, promptingthe prefix malignant to its name [201]. Malignant melanoticschwannoma may be associated with the Carney complex and

typically originates from spinal nerves in the posterior medi-astinum or retroperitoneum.

A single hybrid nerve sheath tumour sharing features ofperineurioma and schwannoma has been reported in the pos-terior mediastinum. These hybrid tumours are commonlyfound in superficial soft tissues and require immunohisto-chemistry to confirm their hybrid nature [157]. Because oftheir coexpression of vimentin and EMA, they need to bedistinguished from meningioma, type A thymoma and follic-ular dendritic cell sarcoma. A single case of myxoidneurothekeoma/nerve sheath myxoma in the superior medias-tinum was recently reported [176].

Neurofibroma, similar to schwannoma, occurs mainly inthe posterior mediastinum. Up to 45 % of neurofibromas oc-cur in patients with neurofibromatosis type I (vonRecklinghausens disease; NF1), in this setting, the tumoursoccur at a younger age and are often multiple [116]. Plexiformneurofibroma is pathognomonic for NF1 and carries a risk oftransformation to MPNST. The anatomical location and ill-defined borders (in contrast to schwannoma) of plexiformneurofibroma hamper removal resulting in a higher recurrencerate.

Table 1 Summary of mediastinal neural tumours

Neural tumours

Derivation Type Behaviour Location in mediastinum/age of onset

Nerve sheath/schwannian Schwannoma Benign Post./adult

Cellular schwannoma Benign Post./adult

Malignant melanoticpsammomatous schwannoma

Malignant Post./adult

Nerve sheath myxoma Benign NA

Hybrid schwannomaperineurioma Benign NA

Neurofibroma Benign Post./all ages

Plexiform neurofibroma Benign Post./young adult

MPNST Malignant Post./all ages

Malignant Triton tumour Malignant Post./all ages

Granular cell tumour Benign Post./young adult

Malignant granular cell tumour Malignant Post./adult

Ganglionic/autonomousnervous system

Sympathetic ganglia, neuronal/neuroblastic

Ganglioneuromas Benign Post./ped./young adult

Neuroblastoma Malignant Post./ped.

Ganglioneuroblastoma Malignant Post./ped.

Paraganglioma Anterior mediastinalbranchiomericchemodectoma

Benign/malignant

Ant./adult

Posterior mediastinal paraganglioma(50 % functional/adrenergic)

Benign/malignant

Post./young adult(male)

Embryonal neural tube remnants Ependymoma Low-grademalignant

Post./na

Neuroectodermal Melanotic neuroectodermal tumour Low-grademalignant

Ped.

Virchows Arch

Malignant peripheral nerve sheath tumours are high-gradesarcomas which typically arise in association with larger nervetrunks and carry a poor prognosis. MPNST, in particular thosearising in NF1-associated neurofibromas, can occur in youngpatients [45, 46]. Similar to other nerve sheath tumours, me-diastinal MPNST is typically located in the posterior compart-ment, although cases may also arise in the anterior mediasti-num [92, 99, 148, 166, 232]. Complete surgical resection mayprovide a cure [105, 124], but overall, these are aggressiveneoplasms with high rates of local recurrence and metastases.Variants of MPNST, which have also been reported in themediastinum, may show divergent mesenchymal differentia-tion with components of skeletal muscle (rhabdomyosarcoma,the so-called Triton tumour) [105], osteosarcoma andchondrosarcoma [44]. MPNST, including the Triton tumourvariant, has been reported as a somatic component of medias-tinal germ cell tumours [33, 118, 131].

Granular cell tumour (GrCT) shows differentiation alongneuroectodermal lines and shares similarities with Schwanncells. GrCT occurs in the posterior mediastinum, in keepingwith its proposed neuroectodermal/neural derivation. Lessthan 20 cases of GrCT have been reported in the mediastinum[1, 4, 8, 15, 40, 76, 87, 95, 98, 117, 137, 159, 168, 170, 179,184, 185, 224], including cases with malignant behaviour oratypical features suggestive of malignant GrCT [40, 76, 137,185]. Benign mediastinal GrCT occurred twice as frequentlyin females as in males; malignant GrCT (four cases) wereequally distributed in males and females. Benign GrCT wereseen in young- to middle-aged adults (range 1153 years, me-dian age 27 years) with an average size of 4 cm and oftendiscovered incidentally. Malignant GrCTs were symptomaticand occurred in older individuals (range 5966 years, medianage 63 years) and were larger (range 5.415 cm, average size10.3 cm).

A very rare tumour with proposed neuroectodermaldifferentiation based on electron microscopic compara-tive studies, melanotic neuroectodermal tumour of infan-cy (retinal anlage tumour, melanotic progronoma),which most commonly occurs in the jaws of infantshas twice been reported in the mediastinum [36, 128].These tumours show a biphasic morphology with smallcells of supposed neural origin which are immunoreac-tive for neuronal/neuroendocrine markers such assynaptophysin and chromogranin, surrounded by largercells with (neuro)ectodermal differentiation evidencedby staining reactions with EMA, cytokeratin andHMB45. Two cases have been reported in the mediasti-num; one case presented in a 7-month-old infant andsecond case was reported in a 23-year-old female whodied of metastases [36, 128].

Neuroblastic tumours with variable ganglionic differenti-ation originating from sympathetic ganglia range from be-nign ganglioneuromas through to malignant neuroblastoma

and the intermediate form, ganglioneuroblastoma [116]. Inline with their postulated cell of origin, most of these tu-mours develop in the posterior mediastinum. Malignantneuroblasticganglionic tumours (neuroblastoma andganglioneuroblastoma) are very rarely encountered in theadult population [11], whilst ganglioneuroma is seen inchildren and young adults and is a benign and oftenasymptomatic tumour (Fig. 3) [116]. Whilst a significantproportion of neuroblastomas present in the mediastinum,it has been suggested that these tumours differ from themore common adrenal neuroblastomas by their pathogene-sis and a more favourable prognosis [116]. A single case ofneuroblastoma as a somatic component of a mediastinalgerm cel l tumour was repor ted , in which theneuroblastemous component metastasized and resulted inthe demise of the patient [144].

Mediastinal paraganglionic tumours of the autonomousnervous system have not infrequently been reported in themediastinum as case series and single case reports, many ofwhich have been included in recent reviews [66, 104, 132,141, 142, 146, 150]. Mediastinal paragangliomas may occurin the anterior mediastinum, where they are associated withaorticopulmonary, vagal, subclavian, carotid and coronaryvessel (branchiomeric) paraganglia. Branchiomeric(aorticopulmonary) paraganglia (chemodectomas) are rarelyfunctional [219].

Paragangliomas located in the posterior compartmentderive from the sympathetic chain and are located in thecostovertebral sulcus and secrete catecholamines in up to50 % of cases, resulting in systemic symptoms (extra-adrenal pheochromocytoma). Mediastinal paragangliomaoccurs over a wide age range; those located in the ante-rior mediastinum are slightly more common in females,whilst paravertebral paraganglioma has slightly more fre-quently been reported in young adult males [66, 132].The biological behaviour of these tumours cannot reli-ably be predicted based on morphological features. Upto a quarter of cases may metastasize [104]. Owing tothe close vicinity of branchomeric paraganglia to medi-astinal vessels and organs and associated surgical consid-erations, the prognosis of this subgroup is worse than forparavertebral paraganglioma.

Remnants of the embryonic neural tube may on very rareoccasions give rise to tumours located in the mediastinum. Sixcases of mediastinal ependymoma, including one case ofmyxopapillary ependymoma, have been published, whichwere summarized in a case report by Estrozi et al. [54]. Allcases occurred in the posterior mediastinum of adult females(age range 3571 years; median age 40.5 years). The tumoursranged in size from 5.0 to 9.0 cm. Of four cases with follow-up, three patients were alive without disease after surgicalresection, and one patient suffered metastases to the pleuraand mediastinal lymph nodes.

Virchows Arch

Tumours of uncertain differentiation

The WHO classification of soft tissue tumours includes achapter on neoplasms with unclear histogenesis, some ofwhich have been reported to occur in the mediastinum(Table 2) and are described in the following section. It isconceivable that a number of these tumours may not actuallyhave a normal tissue counterpart but instead reflect the conse-quence of genetic aberrations in which translocations and oth-er genetic errors culminate in histological patterns, which arenot encountered in normal tissue. A number of the entitiesincluded in this section of the WHO classification are site-specific, such as intra-muscular myxoma, and are not encoun-tered in the mediastinum; those that have been reported in themediastinum are listed in Table 2 and are described in thefollowing section. The term malignant mesenchymomawhich was used in the past for sarcomas with two or moretypes of differentiation is no longer recommended since therespective tumours are now classified as sarcomas with areasof divergent differentiation (e.g. dedifferentiated liposarcomaor Triton tumour).

Angiomatoid fibrous histiocytoma

Despite its name, angiomatoid fibrous histiocytoma is gener-ally considered a tumour of uncertain histogenesis rather thana true fibrohistiocytic tumour (see part I of this review). Twocases of angiomatoid fibrous histiocytoma, which were bothresected without further disease activity, have been reported inthe mediastinum [12, 38].

Ossifying fibromyxoid tumour

Two cases of ossifying fibromyxoid tumour (OFT) havebeen reported in the mediastinum, both in the anterior

compartment [49, 197]. One case presented as a large mass(1,052 g) in a 50-year-old female who complained of chestpain [197]. No evidence of recurrence or metastasis wasnoted 1-year after surgery on follow-up. The second casepresented as an 11-cm tumour in a 59-year-old female; nofollow-up data was provided [49].

Myoepithelial tumours including parachordoma

There have been no convincing reports of myoepithelial tu-mours in the mediastinum. A single case of a myoepthelialtumour located in the inferior mediastinum in close associa-tion with the carina was suggested to originate from heartmuscle and thus cannot be considered a bona fide tumour ofmediastinal soft tissue [10].

Synovial sarcoma

Synovial sarcoma (SySa) is a high-grade spindle cell sarcomaof uncertain histogenesis, often with epithelial differentiation,most commonly occurring in deep soft tissue of the extremi-ties in young adults. SySa is one of the more frequently en-countered sarcomas in the mediastinum.

Salah et al. performed a literature survey of mediastinalSySa and identified 40 cases in the English language withappropriate descriptive details [173], including 15 patientsdescribed in a series by Suster et al. [190]. The majority ofcases occurred in young adults (age range 383 years; medianage 30.5 years) with a male predominance (2.9:1). Seventypercent of cases were reported in the anterior mediastinumwith tumour size ranging from 5 to 20 cm (median size11 cm). Pain and dyspnea were the most common presentingsymptoms.

Most cases were monophasic spindle cell SySa on histolo-gy. A specific chromosomal translocation, t(X;18)(p11;q11),involving the SS18 (SYT, SSXT) gene on chromosome 18 andthe SSX1, SSX2 or SSX4 gene on the X-chromosome is acharacteristic feature of SySa and has been demonstrated inmediastinal SySa [94, 172, 203].

Complete surgical resection was achieved in 57.5 % ofpatients, which was combined with either radiation or chemo-therapy in eight patients. Progression occurred in 67 % ofpatients. Eleven of 30 (37%) patients with follow-up data diedof disease, nine (30 %) were alive with disease and nine(27%) patients were alive with no evidence of disease; diseasestatus was unknown for two patients. Complete resection wasidentified as the sole factor influencing survival.

The differential diagnosis of mediastinal SySa comprisesother spindle cell sarcomas, in particular MPNST, malignantsolitary fibrous tumour (SFT) and pleomorphic sarcoma NOS.Type A thymoma and sarcomatoid carcinoma may also enterthe differential diagnosis.

Table 2 Mediastinal mesenchymal tumours of uncertain differentiation

Tumour type N

Angiomatoid fibrous histiocytoma [12, 38] 2

Ossifying fibromyxoid tumour [49, 197] 2

Myoepithelioma/myoepithelial carcinoma/mixed tumour/parachordoma [10]

1a

Synovial sarcoma

Type A thymoma is usually composed of uniform non-hyperchromatic epithelial spindle cells, whilst the cells in sy-novial sarcoma are hyperchromatic andmitotically active. Theglandular and epithelial components in biphasic synovial sar-coma may be mistaken for elements of type A thymoma.

Immunohistochemistry is very useful. Although synovialsarcoma is usually positive for cytokeratin and EMA, stainingis typically weak and/or focal, whilst type A thymoma is typ-ically diffusely cytokeratin positive. TLE1 and CD56 arecommonly expressed in SySa and not found in type Athymoma, whilst bcl2 expression is found in both. Demon-stration of the t(X;18) translocation by FISH is diagnostic ofSySa, and this genetic abnormality has not been identified inother tumours.

MPNST may be very difficult to distinguish from synovialsarcoma without molecular analysis, as these tumours sharesome morphological and immunohistochemical features.S-100 staining may be seen synovial sarcoma, and converselyMPNST is frequently completely negative for S-100. Similar-ly, staining for TLE1 may also be positive in MPNST andSFT. SFT may be distinguished from SySa by CD34 andSTAT-6 immunohistochemistry, as both markers are notexpressed in SySa.

Epithelioid sarcoma

A single case of mediastinal epithelioid sarcoma was identi-fied in the literature. The tumour was located in the posteriormediastinum of a 1-year-old male infant. After radiotherapyand chemotherapy, no evidence of disease was recorded aftera follow-up period of 44 months [71].

Alveolar soft part sarcoma (ASPS)

Two well-documented cases of primary mediastinal ASPShave been reported to date. ASPS is a rare tumour with adistinctive histology and characteristic genetic translocationwhich arises in the deep soft tissue of the lower limb girdle,most commonly in young individuals. ASPS ultimatelycarries a poor prognosis, and metastases may occur after longtime intervals. The two mediastinal cases described in a reportby Flieder et al. were located in the anterior mediastinum of a23-year-old male and in the posterior mediastinum of a 22-year-old male [59]. One of these patients presented with syn-chronous metastatic disease in the lungs and brain, and thesecond patient was lost to follow-up after 14 years withoutevidence of recurrence or metastasis. A third putative case ofprimary mediastinal ASPS was reported in the anterior medi-astinum of a 13-year-old female. However, during work-up, atumour was later identified in the thigh, which most likelyrepresents the primary location [177].

Clear cell sarcoma of soft tissue

Two cases of clear cell sarcoma (CCS;melanoma of soft parts)have been reported as primary tumours in the mediastinum[194, 199]. A 15-cm tumour was excised from the superiormediastinum of a 59-year-old female in the report byTirabosco et al. [199]. Although the histology was represen-tative for CCS, immunohistochemical staining for HMB45and Melan-A was negative. The diagnosis was supported bydemonstration of a translocation involving the EWSR1 geneby FISH analysis; the partner gene was not identified. Meta-static disease developed 16 months post-surgery; no furtherfollow-up was provided. A second case of CCS was resectedbyVATS from the superior mediastinum of a 63-year-oldmale[194]. A tumour of 8.5 cm was removed and showed thetypical histology for CCS with positive staining for HMB45and S-100 protein. Melan-Awas negative and no genetic anal-ysis was performed. At 15 months of follow-up, there was noevidence of disease.

Extraskeletal myxoid chondrosarcoma

One case o f med ia s t i na l ex t r a ske l e t a l myxo idchondrosa r coma was inc luded in the se r i e s o fchondrosarcoma of Suster et al. [189].

Extrarenal rhabdoid tumour

Extrarenal rhaboid (ERRT) tumour is an exceedingly rare tu-mour, which is histologically similar to its renal and centralnervous system counterparts. ERRToccurs typically in younginfants and carries an exceptionally poor prognosis. TheSMARCB1 (INI1) gene, located on chromosome 22q11, ismutated or deleted in ERRT. Despite its rarity in somatic softtissue, several cases, mainly included in series, have beenreported in the mediastinum [73, 155, 158, 198]. All fivepatients with sufficient clinical details died of disease. Onefemale patient was diagnosed at the age of 26 years, and twopaediatric patients were infants (8 months and a congenitalcase).

PEComa

Tumours with assumed perivascular differentiation and an ep-ithelioid morphology (PEComa) include angiomyolipoma,which contains a variable component of mature fat and mostcommonly arises in the kidney. PEComa cells have a distinctmorphology and immunophenotype with evidence of smoothmuscle and melanocytic differentiation with variable stainingfor smooth muscle actin, desmin and melanocytic markerssuch as Melan-A and HMB45. Since their first description,PEComas have been described in many anatomical locations.

Virchows Arch

PEComa may arise in the setting of tuberous sclerosis andlymphangioleiomyomatosis.

To date, less than 15 cases of PEComa have been reportedin the mediastinum, which have all behaved in a benign fash-ion [6, 18, 26, 63, 78, 96, 97, 134, 200, 212214]. Threequarters of the reported cases were discovered incidentallyby imaging studies for other reasons, symptomatic casesmainly presented with shortness of breath. The marked femalepredominance seen in non-mediastinal cases was less pro-nounced in the mediastinal tumours (2:1). The cases werereported over a wide age range (2263 years; median age54.4 years). Anatomically, the cases were evenly distributedin the anterior (n=5) and posterior (n=4) mediastinum withsingle cases in other compartments, with sizes ranging from 4to 15 cm (average size 7.8 cm). Three of reported cases arelikely to have arisen in association with tuberous sclerosis/lymphangioleiomyomatosis [134, 200, 212].

Desmoplastic small round cell tumour

A single case of desmoplastic small round cell tumour(DSRCT) was reported in the anterior mediastinum of a 22-year-old male [138].

Unclassified/undifferentiated sarcoma

High-grade undifferentiated sarcomas were previously oftenclassified as malignant fibrous histiocytoma (MFH). Follow-ing the current understanding that there is insufficient supportfor histiocytic (or any other specific) differentiation, these tu-mours are now categorized as undifferentiated sarcomas in theWHO classification. So-called MFH cases have been de-scribed in the mediastinum but do not show any further char-acteristic features. A series of 34 so-called MFH cases in themediastinum were reviewed by Murakawa et al. [135], andfurther individual case reports haven been published. As inother soft tissue sites, these tumours are seen over a wideage range but mainly in older adults, with an equal genderdistribution. As would be expected, these tumours have a verypoor prognosis despite therapeutic intervention.

Acknowledgments The authors wish to thank Dr. Satoshi Kaneda(Department of Radiology, Saiseikai Central Hospital, Tokyo, Ja-pan) for providing radiological images, Dr. Ieneke Hartmann (De-partment of Radiology, Maasstad Ziekenhuis, Rotterdam,The Netherlands) for reviewing the radiological images and for pro-viding suggestions for the figure legends. The molecular analysis ofthe epithelioid hemangioendothelioma (Fig. 2) was kindly per-formed by Dr. Uta Flucke (Department of Pathology, Radboud Uni-versity Medical Center, Nijmegen, The Netherlands).

Compliance with Ethical Standards

Conflict of interest The authors declare that they have no competinginterests.

Human and Animal Rights and Informed Consent There was noresearch involving human participants and/or animals performed for thismanuscript.

Open Access This article is distributed under the terms of the CreativeCommons At t r ibut ion 4 .0 In te rna t ional License (h t tp : / /creativecommons.org/licenses/by/4.0/), which permits unrestricted use,distribution, and reproduction in any medium, provided you give appro-priate credit to the original author(s) and the source, provide a link to theCreative Commons license, and indicate if changes were made.

References

1. Abenoza P, Sibley RK (1987) Granular cell myoma andschwannoma: fine structural and immunohistochemical study.Ultrastruct Pathol 11:1928

2. Abiko T, Sato S, Futamata T, Kato R (2005) A case of pleomor-phic leiomyosarcoma of the posterior mediastinum. NipponKokyukigeka Gakkai Zasshi 19:819822

3. Ahmad R, Mayol B, Davis M, Rougraff B (1999) ExtraskeletalEwings sarcoma. Cancer 85:725731

4. Aisner SC, Chakravarthy AK, Joslyn JN, Coughlin TR (1988)Bilateral granular cell tumors of the posterior mediastinum. AnnThorac Surg 46:688689

5. Akiba T, Morikawa T, Hirayama S, Ohki T (2012) Thymichaemangioma presenting with a left innominate vein aneurysm:insight into the aetiology. Interact Cardiovasc Thorac Surg 15:925927. doi:10.1093/icvts/ivs340

6. Amir AM, Zeebregts CJ, Mulder HJ (2004) Anterior mediastinalpresentation of a giant angiomyolipoma. Ann Thorac Surg 78:21612163. doi:10.1016/S0003-4975(03)01512-1

7. Anderson T, Zhang L, Hameed M, Rusch V, Travis WD,Antonescu CR (2015) Thoracic epithelioid malignant vasculartumors: a clinicopathologic study of 52 cases with emphasis onpathologic grading and molecular studies of WWTR1-CAMTA1fusions. Am J Surg Pathol 39:132139. doi:10.1097/PAS.0000000000000346

8. Angeles RM, Papari M, Malecki Z (2005) Pathologic quiz case: a43-year-old woman with an incidentally detected posterior medi-astinal mass. Granular cell tumor of the posterior mediastinum.Arch Pathol Lab Med 129:e27e28. doi:10.1043/1543-2165(2005)1292.0.CO;2

9. Antonescu CR, Le Loarer F, Mosquera JM, Sboner A, Zhang L,Chen CL, Chen HW, Pathan N, Krausz T, Dickson BC,Weinreb I,Rubin MA, Hameed M, Fletcher CD (2013) Novel YAP1-TFE3f u s i o n d e f i n e s a d i s t i n c t s u b s e t o f e p i t h e l i o i dhemangioendothelioma. Genes Chromosomes Cancer 52:775784. doi:10.1002/gcc.22073

10. Arab M, Danel C, dAttellis N, Juvin K, Hernigou A, Fabiani JN,Riquet M (2005) A rare inferior middle mediastinal tumor resec-tion under extra-corporeal circulation. Ann Thorac Surg 79:14131415. doi:10.1016/j.athoracsur.2003.10.019

11. Argani P, Erlandson RA, Rosai J (1997) Thymic neuroblastoma inadults: report of three cases with special emphasis on its associa-tion with the syndrome of inappropriate secretion of antidiuretichormone. Am J Clin Pathol 108:537543

12. Asakura S, Tezuka N, Inoue S, Kihara N, Fujino S (2001)Angiomatoid fibrous histiocytoma in mediastinum. Ann ThoracSurg 72:283285

13. Auliac JB, Cuvelier A, Peillon C, Louvel JP, Metayer J, Muir JF(1999) Mediastinal leiomyosarcoma. RevMal Respir 16:210213

Virchows Arch

14. Baldo X, Sureda C, Gimferrer JM, Belda J (1997) Primary medi-astinal leiomyoma: an angiographic study and embolisation of thefeeding vessels to improve the surgical approach. Eur JCardiothorac Surg 11:574576

15. Bean SM, Eloubeidi MA, Eltoum IA, Cerfolio RJ, Jhala DN(2005) Preoperative diagnosis of a mediastinal granular cell tumorby EUS-FNA: a case report and review of the literature.Cytojournal 2:8. doi:10.1186/1742-6413-2-8

16. Begbie SD, Bell DR, Nevell DF (1997) Mediastinal epithelioidhemangioendothelioma in a patient with type IV Ehlers-Danlossyndrome: a case report and review of the literature. Am J ClinOncol 20:412415

17. Begin LR, Schurch W, Lacoste J, Hiscott J, Melnychuk DA (1994)Glycogen-rich clear cell rhabdomyosarcoma of the mediastinum.Potential diagnostic pitfall. Am J Surg Pathol 18:302308

18. Bertrand G, Bidabe MC, George P, Dubin P, Touzard C (1984)Angiomyolipoma of the central mediastinum. An apparentlyundescribed entity. Ann Chir 38:679681

19. Bhagotra R, Kapoor R, Singhal VS (1990) Leiomyoma of themediastinum. Indian J Chest Dis Allied Sc 32:133136

20. Boor A, Jurkovic I, Janik M, Vajo J, Kocan P, Ponist J, DudrikovaK, Krajcar R, Stubna J (2000) Benign glomus tumor of the supe-rior posterior mediastinum. Cesk Patol 36:156159

21. Box JC, Newman CL, Anastasiades KD, Lucas GW, Latouff OM(1995) Adult rhabdomyoma: presentation as a cervicomediastinalmass (case report and review of the literature). AmSurg 61:271276

22. Brindley GV Jr (1949) Glomus tumor of the mediastinum. JThorac Surg 18:417420

23. Caballero C, Gomez S, Matias-Guiu X, Prat J (1992)Rhabdomyosarcomas developing in association with mediastinalgerm cell tumours. Virchows Arch A Pathol Anat Histopathol420:539543

24. Cakir E, Demirag F, Gulhan E, Oz G, Tastepez I (2009)Mediastinal composite hemangioendothelioma. A rare tumor atan unusual location. Tumori 95:98100

25. Campos J, Otero E, Dominguez MJ, Gonzalez-Quintela A (2007)Epithelioid hemangioendothelioma in the posterior mediastinum.Eur J Intern Med 18:331332. doi:10.1016/j.ejim.2006.11.010

26. Candas F, Berber U, Yildizhan A, Yiyit N, Gorur R, Isitmangil T(2013) Anterior mediastinal angiomyolipoma. Ann Thorac Surg95:14311432. doi:10.1016/j.athoracsur.2012.07.066

27. Carassai P, Caput M (2010) Report of a case of epithelioidhemangioendothelioma of the anterior mediastinum metastatic topleura. Pathologica 102:112114

28. Catanese J, Dutcher JP, Dorfman HD, Andres DF, Wiernik PH(1988) Mediastinal osteosarcoma with extension to lungs in apatient treated for Hodgkins disease. Cancer 62:22522257

29. Chetty R, Reddi A (2003) Rhabdomyomatousmultilocular thymiccyst. Am J Clin Pathol 119:816821. doi:10.1309/QDJC-A1HX-QLHL-CFTM

30. Choi YJ, YangKH, Gang SJ, KimBK, Kim SM (1991)Malignantglomus tumor originating in the superior mediastinuman immu-nohistochemical and ultrastructural study. J Korean Med Sci 6:157163

31. ChuWP (2013) Anterior mediastinal alveolar rhabdomyosarcomain an infant: rare site for a common paediatric tumour. Hong KongMed J 19:458459. doi:10.12809/hkmj133714

32. Cohen AJ, Sbaschnig RJ, Hochholzer L, Lough FC, Albus RA(1987) Mediastinal hemangiomas. Ann Thorac Surg 43:656659

33. Comiter CV, Kibel AS, Richie JP, NucciMR, RenshawAA (1998)Prognostic features of teratomas with malignant transformation: aclinicopathological study of 21 cases. J Urol 159:859863

34. Conner WC, Fink GW, McGinnis KM, Alfieris GM (2004)Surgical management of leiomyosarcoma of the mediastinum.Ann Thorac Surg 77:334336

35. Contreras AL, Punar M, Tamboli P, Tu SM, Pisters L, Moran C,Czerniak BA, Guo CC (2010) Mediastinal germ cell tumors withan angiosarcomatous component: a report of 12 cases. Hum Pathol41:832837. doi:10.1016/j.humpath.2009.11.008

36. DAbrera VS, Burfitt-Williams W (1973) A melanoticneuroectodermal neoplasm of the posterior mediastinum. JPathol 111:165172. doi:10.1002/path.1711110304

37. DAiuto M, Veronesi G, Pompilio G, Gasparri R, Presicci F,Galetta D, Biglioli P, Spaggiari L (2005) Extended right pneumo-nectomy with partial left atrial resection for primaryleiomyosarcoma of the mediastinum. J Thorac Cardiovasc Surg129:694695. doi:10.1016/j.jtcvs.2004.07.057

38. Davies KA, Cope AP, Schofield JB, Chu CQ, Mason JC, KrauszT, Smith P, Denman AM, Walport MJ (1995) A rare mediastinaltumour presenting with systemic effects due to IL-6 and tumournecrosis factor (TNF) production. Clin Exp Immunol 99:117123

39. Davis JM, Mark GJ, Greene R (1978) Benign blood vasculartumors of the mediastinum. Report of four cases and review ofthe literature. Radiology 126:581587. doi:10.1148/126.3.581

40. De Luca G, Luciano A, Benincasa G, Sessa R, Petteruti F (2013)Giant malignant granular cell tumor (GCT) of the posterior medi-astinum. J Thorac Oncol 8:11071108. doi:10.1097/JTO.0b013e318299ad62

41. de Queiroga EM, Chikota H, Bacchi CE, Moran CA, Suster S(2004) Rhabdomyomatous carcinoma of the thymus. Am J SurgPathol 28:12451250

42. Deroux A, Destors M, Coudurier M, Lantuejoul S, Aubert M,Girard N, Moro-Sibilot D (2012) A case of mediastinalangiosarcoma. Rev Mal Respir 29:11201123. doi:10.1016/j.rmr.2012.04.009

43. Doglioni C, Bontempini L, Iuzzolino P, Furlan G, Rosai J (1988)Ependymoma of the mediastinum. Arch Pathol Lab Med 112:194196

44. Ducatman BS, Scheithauer BW (1984) Malignant peripheralnerve sheath tumors with divergent differentiation. Cancer 54:10491057

45. Ducatman BS, Scheithauer BW, Piepgras DG, Reiman HM,Ilstrup DM (1986) Malignant peripheral nerve sheath tumors. Aclinicopathologic study of 120 cases. Cancer 57:20062021

46. Ducatman BS, Scheithauer BW, Piepgras DG, ReimanHM (1984)Malignant peripheral nerve sheath tumors in childhood. J Neuro-Oncol 2:241248

47. Ehrenreich T, Freund AJ, Shapiro HN (1953) Hemangio-endothelioma arising in a mediastinal teratoma. Dis Chest 23:294303

48. Eimoto T, Kitaoka M, Ogawa H, Niwa H, Murase T, Tateyama H,Inagaki H, Soji T, Wang HJ (2002) Thymic sarcomatoid carcino-ma with skeletal muscle differentiation: report of two cases, onewith cytogenetic analysis. Histopathology 40:4657

49. Ekfors TO, Kulju T, Aaltonen M, Kallajoki M (1998)Ossifying fibromyxoid tumour of soft parts: report of fourcases including one mediastinal and one infantile. APMIS106:11241130

50. El Weshi A, Allam A, Ajarim D, Al Dayel F, Pant R, Bazarbashi S,MemonM (2010) Extraskeletal Ewings sarcoma family of tumoursin adults: analysis of 57 patients from a single institution. ClinOncol(R Coll Radiol) 22:374381. doi:10.1016/j.clon.2010.02.010

51. Enjolras O, Wassef M,Mazoyer E, Frieden IJ, Rieu PN, Drouet L,Taieb A, Stalder JF, Escande JP (1997) Infants with Kasabach-Merritt syndrome do not have true hemangiomas. J Pediatr130:631640

52. Eroglu A, Kurkcuoglu C, Karaoglanoglu N, Gursan N (2002)Primary leiomyosarcoma of the anterior mediastinum. Eur JCardiothorac Surg 21:943945

53. Errani C, Zhang L, Sung YS, Hajdu M, Singer S, Maki RG,Healey JH, Antonescu CR (2011) A novel WWTR1-CAMTA1

Virchows Arch

gene fusion is a consistent abnormality in epithelioidhemangioendothelioma of different anatomic sites. GenesChromosomes Cancer 50:644653. doi:10.1002/gcc.20886

54. Estrozi B, Queiroga E, Bacchi CE, Faria Soares de Almeida V,Lucas de Carvalho J, Lageman GM, Rosado-de-Christenson M,Suster S (2006) Myxopapillary ependymoma of the posterior me-diastinum. Ann Diagn Pathol 10:283287. doi:10.1016/j.anndiagpath.2006.03.015

55. Fergeson JO, Clagett OT, Mc DJ (1954) Glomus tumor of themediastinum; review of the literature and report of case. Surgery36:320326

56. Ferretti GR, Chiles C, Woodruff RD, Choplin RH (1998)Epithelioid hemangioendothelioma of the superior vena cava:computed tomography demonstration and review of the literature.J Thorac Imaging 13:4548

57. Fletcher C, Bridge J, Lee J-C (2013) Extra-pleural solitary fibroustumour, 4th edn, WHO classification of tumours of soft tissue andbone. IARC Press, Lyon, pp 8082

58. Fletcher CD, Davies SE, McKee PH (1987) Cellularschwannoma: a dis t inct pseudosarcomatous ent i ty.Histopathology 11:2135

59. Flieder DB, Moran CA, Suster S (1997) Primary alveolar soft-partsarcoma of the mediastinum: a clinicopathological and immuno-histochemical study of two cases. Histopathology 31:469473

60. Flucke U, Vogels RJ, de Saint Aubain Somerhausen N, CreytensDH, Riedl RG, van Gorp JM, Milne AN, Huysentruyt CJ, VerdijkMA, van Asseldonk MM, Suurmeijer AJ, Bras J, Palmedo G,G r o e n e n P J , M e n t z e l T ( 2 0 1 4 ) E p i t h e l i o i dhemangioendothelioma: clinicopathologic, immunohistochemi-cal, and molecular genetic analysis of 39 cases. Diagn Pathol 9:131. doi:10.1186/1746-1596-9-131

61. Fokkema JP, Paul MA, Vrouenraets BC (2014) Mediastinallymphangioma in an adult. Ann R Coll Surg Engl 96:e24e25.doi:10.1308/003588414X13946184901209

62. Folpe AL, Weiss SW (2002) Lipoleiomyosarcoma (well-differen-tiated liposarcoma with leiomyosarcomatous differentiation): aclinicopathologic study of nine cases including one with dediffer-entiation. Am J Surg Pathol 26:742749

63. Fukuzawa J, Shimizu T, Sakai E, Ido A, Fujita Y, Tsuji T, Ohki Y,Kimura T, Fujita M, Onodera S (1992) Case report ofangiomyolipoma of the posterior upper mediastinum. NihonKyobu Shikkan Gakkai Zasshi 30:464467

64. Gaertner EM, Steinberg DM, Huber M, Hayashi T, Tsuda N,Askin FB, Bell SW, Nguyen B, Colby TV, Nishimura SL,Miettinen M, Travis WD (2000) Pulmonary and mediastinal glo-mus tumorsreport of five cases including a pulmonaryglomangiosarcoma: a clinicopathologic study with literature re-view. Am J Surg Pathol 24:11051114

65. Gale AW, Jelihovsky T, Grant AF, Leckie BD, Nicks R (1974)Neurogenic tumors of themediastinum. Ann Thorac Surg 17:434443

66. Gallivan M, Chun B, Rowden G, Lack E (1980) Intrathoracicparavertebral malignant paraganglioma. Arch Pathol Lab Med104:4651

67. Gibbs AR, Johnson NF, Giddings JC, Powell DE, Jasani B (1984)Primary angiosarcoma of the mediastinum: light and electron mi-croscopic demonstration of factor VIII-related antigen in neoplas-tic cells. Hum Pathol 15:687691

68. Gomez-Roman JJ, Val-Bernal JF (1997) Lipoleiomyosarcoma ofthe mediastinum. Pathology 29:428430

69. Gonzalez-Vela JL, Savage PD, Manivel JC, Torkelson JL,Kennedy BJ (1990) Poor prognosis of mediastinal germ cell can-cers containing sarcomatous components. Cancer 66:11141116

70. Greenwood SM, Meschter SC (1989) Extraskeletal osteogenicsarcoma of the mediastinum. Arch Pathol Lab Med 113:430433

71. Gross E, Rao BN, Pappo A, Bowman L, Shearer P, Kaste S,Greenwald C, Michalkiewicz E, Pratt C (1996) Epithelioid sarco-ma in children. J Pediatr Surg 31:16631665

72. Gupta S, Jindal SK, Vashisht R, Singh H, Malik SK (1983)Leiomyosarcoma of the mediastinum. Eur J Respir Dis 64:6971

73. Gururangan S, Bowman LC, Parham DM, Wilimas JA, Rao B,Pratt CB, Douglass EC (1993) Primary extracranial rhabdoid tu-mors. Clinicopathologic features and response to ifosfamide.Cancer 71:26532659

74. Halefoglu AM (2013) Extraskeletal Ewings sarcoma presentingas a posterior mediastinal mass. Arch Bronconeumol 49:8284.doi:10.1016/j.arbres.2012.02.020

75. Halliday J, Soon SY, Monaghan H,Walker WS, Zamvar V (2010)Extraskeletal Ewings sarcoma presenting as a mediastinal mass.Ann Thorac Surg 90:10161017. doi:10.1016/j.athoracsur.2010.01.083

76. Harrer WV, Patchefsky AS (1972) Malignant granular-cellmyoblastoma of the posterior mediastinum. Chest 61:9596

77. Hartman KR, Moncur JT, Minniti CP, Creamer KM (2009)Mediastinal Kaposiform hemangioendothelioma and Kasabach-Merritt phenomenon in an infant: treatment with interferon. JPediatr Hematol Oncol 31:690692. doi:10.1097/MPH.0b013e3181a1c291

78. Hayashi K, Yamamoto M, Nishimura H, Inou N (1994)Angiomyolipoma of the anterior mediastinuma case report.Nihon Kyobu Geka Gakkai Zasshi 42:584587

79. Herlitzka AJ, Gale JW (1958) Tumors and cysts of the mediasti-num; survey of one hundred seventy-four mediastinal tumorstreated surgically during the past eighteen years at the Universityof Wisconsin Hospitals. AMA Arch Surg 76:697706

80. Hilliard RI, McKendry JB, Phillips MJ (1990) Congenital abnor-malities of the lymphatic system: a new clinical classification.Pediatrics 86:988994

81. Hiraiwa H, Hamazaki M, Tsuruta S, Hattori H, Mimaya J,Hasegawa S , Kohno S , Aok i K (1998) In f an t i l ehemangioendothelioma of the thymus with massive pleural effu-sion and KasabachMerritt syndrome: histopathological, flowcytometrical analysis of the tumor. Acta Paediatr Jpn 40:604607

82. Hirano H, Kizaki T, Sashikata T, Maeda T, Yoshii Y (2003)Leiomyosarcoma arising from soft tissue tumor of the mediasti-num. Med Electron Microsc 36:5258. doi:10.1007/s007950300007

83. Hirose T, Hasegawa T, Seki K, Yang P, Sano T, Morizumi H,Tsuyuguchi M (1996) Atypical glomus tumor in the mediastinum:a case report with immunohistochemical and ultrastructural stud-ies. Ultrastruct Pathol 20:451456

84. Hishida T, Yoshida J, Nishimura M, Ishii G, Nakao M, Nagai K(2009) Extraskeletal osteosarcoma arising in anterior mediasti-num: brief report with a review of the literature. J Thorac Oncol4:927929. doi:10.1097/JTO.0b013e3181a52c63

85. Hoseok I, Jeong YJ, Choi KU, Kim YD (2008) Symptomaticposterior mediastinal angioleiomyoma. Yonsei Med J 49:666668. doi:10.3349/ymj.2008.49.4.666

86. Ikeda T, Ishihara T, Yoshimatsu H, Kikuchi K, Murakami M(1974) Primary osteogenic sarcoma of the mediastinum. Thorax29:582588

87. Ishibashi H, Ota S, Hirose M, Tanio N, Fukuchi K, Muro H,Nakajima N (2010) Granular cell tumor in themediastinum; reportof a case. Kyobu Geka 63:496499

88. Isowa N, Hasegawa S, Mino M, Morimoto K, Wada H (2002)Mediastinal epithelioid hemangioendothelioma resected byhemi-plastron window technique. Ann Thorac Surg 74:567569

89. Iwami D, Shimaoka S, Mochizuki I, Sakuma T (2006)Kaposiform hemangioendothelioma of the mediastinum in a 7-

Virchows Arch

month-old boy: a case report. J Pediatr Surg 41:14861488. doi:10.1016/j.jpedsurg.2006.04.013

90. Iwata T, Miura T, Inoue K, Hanada S, Inoue H, Miyamoto Y(2012) Primary leiomyosarcoma of the anterior mediastinumencasing the aortic arch, left common carotid and left subclavianarteries. Ann Thorac Cardiovasc Surg 18:140143

91. Jeong SS, Choi PJ, Kim DW, Son C, Roh MS (2013) Primaryextraskeletal mesenchymal chondrosarcoma of the anterior medi-astinum. Korean J Pathol 47:492494. doi:10.4132/KoreanJPathol.2013.47.5.492

92. Kalra B, Kingsley PA, Bedi HS, Kwatra KS, Negi P (2014)Malignant peripheral nerve sheath tumor of the anterior mediasti-num: a rare presentation. Rare Tumors 6:5528. doi:10.4081/rt.2014.5528

93. Kardamakis D, Bouboulis N, Ravazoula P, Dimopoulos P,Dougenis D (1996) Primary hemangiosarcoma of the mediasti-num. Lung Cancer 16:8186

94. Katakura H, Fukuse T, Shiraishi I, Hayatsu E, Nishijo K,Toguchida J, Nakashima Y, Wada H (2009) Mediastinal synovialsarcoma. Thorac Cardiovasc Surg 57:183185. doi:10.1055/s-2006-955886

95. Kim do Y, Jeon HW, Kim KS, Park JK, Sung SW (2014) A rarecase of mediastinal granular cell tumor. Korean J ThoracCardiovasc Surg 47:494496. doi:10.5090/kjtcs.2014.47.5.494

96. Kim YH, Kwon NY, Myung NH, Kim EJ, Choi YH, Yoon SY,Choi EK, Park JS, Kim KY, Lee KY (2001) A case of mediastinalangiomyolipoma. Korean J Intern Med 16:277280

97. Knight CS, Cerfolio RJ, Winokur TS (2008) Angiomyolipoma ofthe anterior mediastinum. Ann Diagn Pathol 12:293295. doi:10.1016/j.anndiagpath.2006.12.007

98. Kocatas A, Dural AC, Sever N, Kankaya B, Dogan M, Yegen G,Gonenc M, Bilgic BM, Bedirhan MA, Alis H (2014) Minimalinvasive endoscopic management of synchronous granular celltumours in the colon and posterior mediastinum. J MinimAccess Surg 10:3436. doi:10.4103/0972-9941.124469

99. Koezuka S, Hata Y, Sato F, Otsuka H,Makino T, Tochigi N, IyodaA (2014) Malignant peripheral nerve sheath tumor in the anteriormediastinum: a case report. Mol Clin Oncol 2:987990. doi:10.3892/mco.2014.343

100. Koizumi K, Haraguchi S, Mikami I, Kubokura H, Okada D,Yamagishi S, Kinoshita H, Enomoto Y, Shimizu K, Maeda M(2005) Video-assisted thoracic surgery for Ewings sarcoma ofthe mediastinum in a 3-year-old girl. Ann Thorac CardiovascSurg 11:117120

101. Kuschill-Dziurda J, Mastalerz L, Grzanka P, Nizankowska-Mogilnicka E (2009) Rhabdomyoma as a tumor of the posteriormediastinum. Pol Arch Med Wewn 119:599602

102. Kuzucu A, Erkal HS, Soysal O, Serin M (2006) ExtraskeletalEwings sarcoma presenting with multifocal intrathoracic masslesions associated with mediastinal shift. Ann Thorac Surg 81:14871488. doi:10.1016/j.athoracsur.2005.03.116

103. Lamovec J, Sobel HJ, Zidar A, Jerman J (1990) Epithelioidhemangioendothelioma of the anterior mediastinum withosteoclast-like giant cells. Light microscopic, immunohistochemi-cal, and electron microscopic study. Am J Clin Pathol 93:813817

104. Lamy AL, Fradet GJ, Luoma A, Nelems B (1994) Anterior andmiddle mediastinum paraganglioma: complete resection is thetreatment of choice. Ann Thorac Surg 57:249252

105. Lang-Lazdunski L, Pons F, Jancovici R (2003)Malignant Tritontumor of the posterior mediastinum: prolonged survival afterstaged resection. Ann Thorac Surg 75:16451648

106. Lazure T, Essamet W, Palazzo L, Epardeau B, Fabre M (2001)Cytological findings of a primary mediastino-pulmonaryleiomyosarcoma. Report of a case diagnosed by endoscopicultrasonography-guided fine needle aspiration. Cytopathology12:410413

107. Lee DH, Park CK, Keum DY, Kim JB, Hwang I (2012)Leiomyosarcoma of the posterior mediastinum extending intothe adjacent spinal canal. Korean J Thorac Cardiovasc Surg 45:192195. doi:10.5090/kjtcs.2012.45.3.192

108. Lee TJ, Reddy GP, Leung JW, Gotway MB (2008) Mediastinalglomangioma: CT and octreotide scintigraphy appearance, andreview of the literature. J Thorac Imaging 23:289291. doi:10.1097/RTI.0b013e31817eee70

109. Li XM, Lin XY, XuHT, Yu JH,Wang L, Fan CF, Liu Y,Wang EH(2013) Mediastinal epithelioid hemangioendothelioma with abun-dant spindle cells and osteoclast-like giant cells mimicking malig-nant fibrous histiocytoma. Diagn Pathol 8:103. doi:10.1186/1746-1596-8-103

110. Lin J, Ho J, Chan A, Yeo W, Yip KM, Johnson PJ (1995)Extraosseous osteogenic sarcoma of the mediastinum occurringin a Chinese patient. Clin Oncol (R Coll Radiol) 7:200201

111. Lincoln JC (1965) Leiomyosarcoma of the anterior mediastinum.Thorax 20:362366

112. Linnoila RI, Tsokos M, Triche TJ, Marangos PJ, Chandra RS(1986) Evidence for neural origin and PAS-positive variants ofthe malignant small cell tumor of thoracopulmonary region(Askin tumor). Am J Surg Pathol 10:124133

113. Lodding P, Kindblom LG, Angervall L, Stenman G (1990)Cellular schwannoma. A clinicopathologic study of 29cases. Virchows Arch A Pathol Anat Histopathol 416:237248

114. Lyons LL, North PE, Mac-Moune Lai F, Stoler MH, Folpe AL,Weiss SW (2004) Kaposiform hemangioendothelioma: a study of33 cases emphasizing its pathologic, immunophenotypic, and bi-ologic uniqueness from juvenile hemangioma. Am J Surg Pathol28:559568

115. Maamouri F, Ennaifer Jerbi E, Tounsi Guettiti H, Boussen H,Dellagi K, Boubaker S (2008) Multicentric epithelioidhemangioendothelioma involving lung, mediastinum and liver.Tunis Med 86:616617

116. Macchiarini P, Ostertag H (2004) Uncommon primary mediastinaltumours. Lancet Oncol 5:107118. doi:10.1016/S1470-2045(04)01385-3

117. Machida E, HaniudaM, Eguchi T, KuraiM,Yamanda T, Amano J,Ota H (2003) Granular cell tumor of the mediastinum. Intern Med42:178181

118. Malagon HD, Valdez AM, Moran CA, Suster S (2007) Germ celltumors with sarcomatous components: a clinicopathologic andimmunohistochemical study of 46 cases. Am J Surg Pathol 31:13561362. doi:10.1097/PAS.0b013e318033c7c4

119. Manduch M, Dexter DF, Ellis PM, Reid K, Isotalo PA (2008)Extraskeletal Ewings sarcoma/primitive neuroectodermal tumorof the posterior mediastinum with t(11;22)(q24;q12). Tumori 94:888891

120. Manivel C, Wick MR, Abenoza P, Rosai J (1986) The occurrenceof sarcomatous components in primary mediastinal germ cell tu-mors. Am J Surg Pathol 10:711717

121. Mansour Z, Neuville A, Massard G (2010)Mediastinal epithelioidhaemangioendothelioma: a rare mediastinal tumour. InteractCardiovasc Thorac Surg 10:122124. doi:10.1510/icvts.2009.216978

122. Marchevsky AM (1999) Mediastinal tumors of peripheral nervoussystem origin. Semin Diagn Pathol 16:6578

123. Matsuoka H, Nishio W, Sakamoto T, Harada H, Sashikata T,Tsubota N (2002) Mediastinal angioleiomyoma. Ann ThoracSurg 73:16531654

124. McConnell YJ, Giacomantonio CA (2012) Malignant triton tu-morscomplete surgical resection and adjuvant radiotherapy as-sociated with improved survival. J Surg Oncol 106:5156. doi:10.1002/jso.23042

Virchows Arch

125. Michel M, Pratt JW (2004) Anterior mediastinal nonseminomatousgerm cell tumor with malignant transformation: a case report. CurrSurg 61:576579. doi:10.1016/j.cursur.2004.05.021

126. Miller R, Kurtz SM, Powers JM (1978)Mediastinal rhabdomyoma.Cancer 42:19831988

127. Mineo TC, Biancari F, Cristino B, DAndrea V (1995) Benignvascular tumours of the mediastinum: presentation of three casesand review of the literature. Thorac Cardiovasc Surg 43:361364.doi:10.1055/s-2007-1013811

128. Misugi K, Okajima H, NewtonWA Jr, Kmetz DR, Delorimier AA(1965) Mediastinal origin of a melanotic progonoma or retinalanlage tumor: ultrastructural evidence for neural crest origin.Cancer 18:477484

129. Moran CA, Koss MN (1993) Rhabdomyomatous thymoma. Am JSurg Pathol 17:633636

130. Moran CA, Suster S (1995) Mediastinal hemangiomas: a study of18 cases with emphasis on the spectrum of morphological fea-tures. Hum Pathol 26:416421

131. Moran CA, Suster S (1997) Primary germ cell tumors of the me-diastinum: I. Analysis of 322 cases with special emphasis onteratomatous lesions and a proposal for histopathologic classifica-tion and clinical staging. Cancer 80:681690

132. Moran CA, Suster S, Fishback N, Koss MN (1993) Mediastinalparagangliomas. A clinicopathologic and immunohistochemicalstudy of 16 cases. Cancer 72:23582364

133. Moran CA, Suster S, Perino G, Kaneko M, Koss MN (1994)Malignant smooth muscle tumors presenting as mediastinal softtissue masses. A clinicopathologic study of 10 cases. Cancer 74:22512260

134. Morita K, Shida Y, Shinozaki K, Uehara S, Seto T, Sugio K,Ichinose Y, Nishiyama K, Matsuo Y, Hatakenaka M, Honda H(2012) Angiomyolipomas of the mediastinum and the lung. JTho ra c Imag ing 27 :W21W23. do i : 10 . 1097 /RTI .0b013e31823150c7

135. Murakawa T, Nakajima J, Fukami T, Tanaka M, Takeuchi E,Takamoto S (2001) Malignant fibrous histiocytoma in the anteriormediastinum. Jpn J Thorac Cardiovasc Surg 49:722727

136. Nakamura M, Tachibana H, Mukaeyama T (1996) A case ofleiomyoma of the posterior mediastinum. Nihon Kyobu GekaGakkai Zasshi 44:20822086

137. Nakao M, Hishida T, Ishii G, Yoshida J, Nishimura M, Nagai K(2012)Malignant granular cell tumor of the posterior mediastinumwith dissemination. Asian Cardiovasc Thorac Ann 20:7173. doi:10.1177/0218492311421453

138. Nayak HK, Vangipuram DR, Sonika U, Kar P, Kumar N, KapoorN (2011) Mediastinal massa rare presentation of desmoplasticsmall round cell tumour. BMJ Case Rep 2011. doi: 10.1136/bcr.10.2011.5042

139. Niwa H, Kondou K, Sekiguchi K (1988) A case of mediastinalleiomyoma associated with cystic change and calcificationa re-view of 7 cases in Japanese literatures. NihonKyobu Geka GakkaiZasshi 36:21362139

140. ORegan GM, IrvineAD, YaoN, OMarcaigh A, Sheridan-PereiraM, Phelan E, McDermott MB, Twomey A, Russell J, Watson R(2009) Mediastinal and neck kaposiform hemangioendothelioma:report of three cases. Pediatr Dermatol 26:331337. doi:10.1111/j.1525-1470.2009.00913.x

141. Odze R, Begin L (1990)Malignant paraganglioma of the posteriormediastinum. Cancer 65:667694

142. Odze R, Begin LR (1990) Malignant paraganglioma of the poste-rior mediastinum. A case report and review of the literature.Cancer 65:564569

143. Ohebsion J, OConnor WN, Attili AK, Diaz-Guzman E (2010) A30-year-old man with facial flushing and a mediastinal mass.Chest 138:746749. doi:10.1378/chest.09-2847

144. Ohtsuka M, Satoh H, Inoue M, Yazawa T, Yamashita YT,Sekizawa K, Hasegawa S (2000) Disseminated metastasis ofneuroblastomatous component in immature mediastinal teratoma:a case report. Anticancer Res 20:527530

145. Okudela K, Nakamura N, Sano J, Ito T, Kitamura H (2001) Thymiccarcinosarcoma consisting of squamous cell carcinomatous and em-bryonal rhabdomyosarcomatous components. Report of a case andreview of the literature. Pathol Res Pract 197:205210

146. Olson J, Sayler W (1978) Mediastinal paragangliomas (aorticbody tumor): a report of four cases and a review of the literature.Cancer 41:24052412

147. Oshikiri T, Morikawa T, Jinushi E, Kawakami Y, Katoh H (2001)Five cases of the lymphangioma of the mediastinum in adult. AnnThorac Cardiovasc Surg 7:103105

148. Otani Y, Morishita Y, Yoshida I, Ishikawa S, Otaki A, Aihara T,Nakajima T (1996) A malignant Triton tumor in the anterior me-diastinum requiring emergency surgery: report of a case. SurgToday 26:834836

149. Ouadnouni Y, Achir A, Bekarsabein S, Bouchikh M, Smahi M,Msougar Y, Mahassini N, Benosman A (2009) Primary mediasti-nal leiomyoma: a case report. Cases J 2:8555. doi:10.4076/1757-1626-2-8555

150. Pachter MR (1963) Mediastinal nonchromaffin paraganglioma. Aclinicopathologic study based on eight cases. J Thorac CardiovascSurg 45:152160

151. Pachter MR, Lattes R (1963) Mesenchymal tumors of the medi-astinum II. Tumors of blood vascular origin. Cancer 16:95107

152. Panasuk DB, Bauer TL, Davies AL, Schneider C, Flynn C (2003)Commonmalignancies with uncommon sites of presentation: case1. Anterior mediastinal rhabdomyosarcoma. J Clin Oncol 21:44554456. doi:10.1200/JCO.2003.03.149

153. Pandit S, Mukherjee S, Bhattacharya S, Dattachaudhuri A,Bhuniya S, Deb J, Bhanja P (2012) A rare mediastinal tumourin a young male mimicking massive pleural effusion. Lung India29:6669. doi:10.4103/0970-2113.92368

154. Papagiannopoulos K, Sheppard MN, Goldstraw P (2000) Thymichemangioma presenting with recurrent pleural effusion. AnnThorac Surg 70:297299

155. Parham DM, Weeks DA, Beckwith JB (1994) The clinicopatho-logic spectrum of putative extrarenal rhabdoid tumors. An analysisof 42 cases studied with immunohistochemistry or electron mi-croscopy. Am J Surg Pathol 18:10101029

156. Park JG, AubryMC, Godfrey JA,Midthun DE (2006)Mediastinallymphangioma: Mayo Clinic experience of 25 cases. Mayo ClinProc 81:11971203. doi:10.4065/81.9.1197

157. Park JY, Park NJ, Kim SP, Kwon KY, Lee SS (2012) A soft tissueperineurioma and a hybrid tumor of perineurioma andschwannoma. Korean J Pathol 46:7578. doi:10.4132/KoreanJPathol.2012.46.1.75

158. Perlman EJ, Ali SZ, Robinson R, Lindato R, Griffin CA (1998)Infantile extrarenal rhabdoid tumor. Pediatr Dev Pathol 1:149152

159. Ponce FA, Killory BD, Wait SD, Theodore N, Dickman CA(2011) Endoscopic resection of intrathoracic tumors: experiencewith and long-term results for 26 patients. J Neurosurg Spine 14:377381. doi:10.3171/2010.11.SPINE09718

160. Qi Y, Chang B, Pang L, Liu C, Li F (2011) Solid alveolar rhab-domyosarcoma with spindle-shaped cells and epithelial differenti-ation of the mediastinum in a 68-year-old man: a case report andliterature review. J Cancer Res Ther 7:353356. doi:10.4103/0973-1482.87009

161. Quan GM, Irons S, Scripcaru G, Tang SK (2014) Posterior medi-astinal paraspinal angioleiomyoma causing thoracicradiculopathy. ANZ J Surg. doi:10.1111/ans.12639

162. Rajasingham AS, Cooray GH (1954) A large leiomyoma of themediastinum. Br J Surg 41:446447

Virchows Arch

163. Rasaretnam R, Panabokke RG (1975) Leiomyosarcoma of themediastinum. Br J Dis Chest 69:6369

164. Reali A, Mortellaro G, Allis S, Trevisiol E, Anglesio SM,Bartoncini S, Ruo Redda MG (2013) A case of primary medias-tinal Ewings sarcoma/primitive neuroectodermal tumor present-ing with initial compression of superior vena cava. Ann ThoracMed 8:121123. doi:10.4103/1817-1737.109834

165. Reeder LB (2000) Neurogenic tumors of the mediastinum. SeminThorac Cardiovasc Surg 12:261267

166. RenW, XuX, Yan J, Qian X, Liu B (2014) Malignant triton tumorof the anterior mediastinum: a case report. Oncol Lett 7:807810.doi:10.3892/ol.2014.1787

167. Ribet ME, Cardot GR (1994) Neurogenic tumors of the thorax.Ann Thorac Surg 58:10911095

168. Robinson JM, Knoll R, Henry DA (1988) Intrathoracic granularcell myoblastoma. South Med J 81:14531457

169. Romano R, Cesario A, Lococo F, Petrone G, Margaritora S,Granone P (2013) Successful multidisciplinary management of aprimary mediastinal Ewings sarcoma. Minerva Chir 68:121124

170. Rosenbloom PM, Barrows GH, Kmetz DR, Canty TG (1975)Granular cell myoblastoma arising from the thoracic sympatheticnerve chain. J Pediatr Surg 10:819822

171. Saito A, Watanabe K, Kusakabe T, Abe M, Suzuki T (1998)Mediastinal mature teratoma with coexistence of angiosarcoma,granulocytic sarcoma and a hematopoietic region in the tumor: arare case of association between hematological malignancy andmediastinal germ cell tumor. Pathol Int 48:749753

172. Salah S, Al-Ibraheem A, Daboor A, Al-Hussaini M (2013)Synovial sarcoma presenting with huge mediastinal mass: a casereport and review of the literature. BMC Res Notes 6:240

173. Salah S, Salem A (2014) Primary synovial sarcomas of the medi-astinum: a systematic review and pooled analysis of the publishedliterature. ISRN Oncol 2014:412527. doi:10.1155/2014/412527

174. Salih Deveci M, Ceyhan K, Deveci G, Finci R (2001) Pericardialrhabdomyomatous spindle cell thymoma with mucinous cysticdegeneration. Histopathology 38:479481

175. Sartelet H, Lantuejoul S, Armari-Alla C, Pin I, Delattre O,Brambilla E (1998) Solid alveolar rhabdomyosarcoma of the tho-rax in a child. Histopathology 32:165171

176. Sayan M, Celik A, Ertunc O, Uluoglu O, Tastepe AI (2014)Mediastinal neurothekeoma: a rare tumor. Asian CardiovascThorac Ann. doi:10.1177/0218492314552857

177. Schenning R, Vajtai P, Troxell M, Pollock J, Hopkins K (2013)Alveolar soft part sarcoma: unusual etiology of mediastinal massin an adolescent. Clin Pract 3:e26. doi:10.4081/cp.2013.e26

178. Schulman H, Newman-Heinman N, Kurtzbart E, Maor E, ZirkinH, Laufer L (2000) Thoracoabdominal peripheral primitiveneuroectodermal tumors in childhood: radiological features. EurRadiol 10:16491652. doi:10.1007/s003300000367

179. Segawa M, Kusajima Y, Senda K, Saito K (2007) Mediastinalgranular cell tumor arising from the left recurrent nerve; reportof a case. Kyobu Geka 60:595598

180. Shaffer K, Pugatch RD, Sugarbaker DJ (1990) Primary mediasti-nal leiomyoma. Ann Thorac Surg 50:301302

181. Short M, Dramis A, Ramani P, Parikh DH (2008) Mediastinal andpulmonary infantile myofibromatosis: an unusual surgical presen-tation. J Pediatr Surg 43:e29e31. doi:10.1016/j.jpedsurg.2008.06.046

182. Sidhu JS, NicolasMM,TaylorW (2002)Mediastinal rhabdomyoma:a case report and review of the literature. Int J Surg Pathol 10:313318

183. Siraj F, Dhawan S, Jain D (2011) Invasive thymoma with osseousmetaplasia and cystic change in a case of myasthenia gravis: a rarepresentation. Gen Thorac Cardiovasc Surg 59:583586. doi:10.1007/s11748-010-0726-4

184. Smith AR, Gilbert CF, Strausbauch P, Silverman JF (1998) Fineneedle aspiration cytology of a mediastinal granular cell tumorwith histologic confirmation and ancillary studies. A case report.Acta Cytol 42:10111016

185. Soh WM, Yeong ML, Wong KP (2014) Malignant granular celltumour of the mediastinum. Malays J Pathol 36:149151

186. Stark P, Smith DC, Watkins GE, Chun KE (1990) Primary intra-thoracic extraosseous osteogenic sarcoma: report of three cases.Radiology 174:725726. doi:10.1148/radiology.174.3.2305056

187. Steen BC, Florez Martin S, Fernandez Fau L, Garcia Tirado J,Jareno Esteban J, Ancochea Bermudez J (1993) Mediastinalleiomyosarcoma. An Med Interna 10:8385

188. Sunderrajan EV, Luger AM, Rosenholtz MJ, Maltby JD (1984)Leiomyosarcoma in the mediastinum presenting as superior venacava syndrome. Cancer 53:25532556

189. Suster S, Moran CA (1997) Malignant cartilaginous tumors of themediastinum: clinicopathological study of six cases presenting asextraskeletal soft tissue masses. Hum Pathol 28:588594

190. Suster S, Moran CA (2005) Primary synovial sarcomas of themediastinum: a clinicopathologic, immunohistochemical, and ul-trastructural study of 15 cases. Am J Surg Pathol 29:569578

191. Suster S, Moran CA, Koss MN (1994) Epithelioid hemangio-endothelioma of the anterior mediastinum. Clinicopathologic, im-munohistochemical, and ultrastructural analysis of 12 cases. Am JSurg Pathol 18:871881

192. Suster S, Moran CA, KossMN (1994) Rhabdomyosarcomas of theanterior mediastinum: report of four cases unassociated with germcell, teratomatous, or thymic carcinomatous components. HumPathol 25:349356

193. Tajima H, Tajima N, Yamamoto K,Maeda S, Koizumi K, KumazakiT, Yoshida H, Egami K (1995) Anterior mediastinal schwannoma: acase report. Radiat Med 13:175177

194. Tanaka Y, Yoshimasu T, Oura S, Hirai Y, Kawago M, Okamura Y(2014) Primary clear-cell sarcoma in the mediastinum. Case RepOncol 7:306309. doi:10.1159/000363180

195. Tane S, Tanaka Y, Tauchi S, Uchino K, Nakai R, Yoshimura M(2011) Radically resected epithelioid angiosarcoma that originatedin the mediastinum. Gen Thorac Cardiovasc Surg 59:503506.doi:10.1007/s11748-010-0710-z

196. Tarr RW, Kerner T, McCook B, Page DL, Nance EP, Kaye JJ(1988) Primary extraosseous osteogenic sarcoma of the mediasti-num: clinical, pathologic, and radiologic correlation. South Med J81:13171319

197. Teh BM, Nickless D, Seevanayagam S (2011) Malignant ossify-ing fibromyxoid tumour: a large anterior mediastinal mass.Pathology 43:749751. doi:10.1097/PAT.0b013e32834c72b1

198. Thomson TA, Klijanienko J, Couturier J, Brisse H, Pierron G,Freneaux P, Sastre-Garau X, Lagace R, Bourdeaut F (2011)Fine-needle aspiration of renal and extrarenal rhabdoid tumors:the experience of the Institut Curie regarding 20 tumors in 13patients. Cancer Cytopathol 119:4957. doi:10.1002/cncy.20121

199. Tirabosco R, Lang-Lazdunski L, Diss TC, AmaryMF, Rodriguez-Justo M, Landau D, Lorenzi W, Flanagan AM (2009) Clear cellsarcoma of the mediastinum. Ann Diagn Pathol 13:197200. doi:10.1016/j.anndiagpath.2008.02.014

200. Torigian DA, Kaiser LR, Soma LA, Tomaszewski JE, Kotloff R,Siegelman ES (2002) Symptomatic dysrhythmia caused by a pos-terior mediastinal angiomyolipoma. AJR Am J Roentgenol 178:9396. doi:10.2214/ajr.178.1.1780093

201. Torres-Mora J, Dry S, Li X, Binder S, Amin M, Folpe AL (2014)Malignant melanotic schwannian tumor: a clinicopathologic, im-munohistochemical, and gene expression profiling study of 40cases, with a proposal for the reclassification of melanoticschwannoma. Am J Surg Pathol 38:94105. doi:10.1097/PAS.0b013e3182a0a150

Virchows Arch

202. Toursarkissian B, OConnor WN, Dillon ML (1990) Mediastinalepithelioid hemangioendothelioma. Ann Thorac Surg 49:680685

203. Trupiano JK, Rice TW, Herzog K, Barr FG, Shipley J, Fisher C,Goldblum JR (2002) Mediastinal synovial sarcoma: report of twocases with molecular genetic analysis. Ann Thorac Surg 73:628630

204. Ulusakarya A, Terrier P, Regnard JF, de Montpreville V, MunckJN (1999) Extraskeletal osteosarcoma of the mediastinum aftertreatment of a mediastinal germ-cell tumor. Am J Clin Oncol 22:609614

205. Uno A, Sakurai M, Onuma K, Yamane Y, Kurita K, Hayashi I,Ikeda M, Hagiwara N, Tominaga K, Hakozaki H (1988) A case ofgiant mediastinal leiomyoma with long-term survival. Tohoku JExp Med 156:16

206. Vaish AK, Verma SK, Shakya S, Goel MM (2012) Schwannomain anterior mediastinum with massive pericardial effusion. BMJCase Rep 2012. doi: 10.1136/bcr-2012-007867

207. Van Schil PE, Colpaert CG, Van Look R, Van OosteromAT, EAVm, Reher SW, Schoofs EL (1993) Primary mediastinalleiomyosarcoma. Thorac Cardiovasc Surg 41:377378. doi:10.1055/s-2007-1013895

208. Venuta F, Pescarmona EO, Rendina EA, Ciriaco P, De Giacomo T,Ricci C (1993) Primary osteogenic sarcoma of the posterior me-diastinum. Case report. Scand J Thorac Cardiovasc Surg 27:169173

209. Vrtik M, Larbalestier RI, Cameron D, Gupta A, Sinniah R (2004)Giant superior mediastinal angioleiomyoma. J Thorac CardiovascSurg 128:786788. doi:10.1016/j.jtcvs.2004.03.035

210. Wallenstein MB, Hole MK, McCarthy C, Fijalkowski N, Jeng M,Wo n g W B ( 2 0 1 4 ) M e d i a s t i n a l K a p o s i f o r mhemangioendothelioma and Kasabach-Merritt phenomenon in apatient with no skin changes and a normal chest CT. PediatrHematol Oncol. doi:10.3109/08880018.2013.825356

211. Walsh MA, Carcao M, Pope E, Lee KJ (2008) Kaposiformhemangioendothelioma presenting antenatally with a pericardialeffusion. J Pediatr Hematol Oncol 30:761763. doi:10.1097/MPH.0b013e318175c244

212. Warth A, Herpel E, Schmahl A, Hoffmann H, Herth FJ,Schirmacher P, Dienemann H, Schnabel PA (2008) Mediastinalangiomyolipomas in a male patient affected by tuberous sclerosis.Eur Respir J 31:678680. doi:10.1183/09031936.00021207

213. Watanabe S, Sato H, Tawaraya K, Tsubota M, Endo M, Seki M(1997) A case of mediastinal angiomyolipoma. Nihon KyobuGeka Gakkai Zasshi 45:18891892

214. Watts KA, Watts JR Jr (2007) Incidental discovery of an anteriormediastinal angiomyolipoma. J Thorac Imaging 22:180181. doi:10.1097/01.rti.0000213571.09280.f8

215. Weidner N (1991) Atypical tumor of the mediastinum: epithelioidhemangioendothelioma containing metaplastic bone andosteoclastlike giant cells. Ultrastruct Pathol 15:481488

216. Weiss SW, Enzinger FM (1982) Epithelioid hemangioendothelioma:a vascular tumor oftenmistaken for a carcinoma. Cancer 50:970981

217. Weissferdt A, Kalhor N, Suster S, Moran CA (2010) Primaryangiosarcomas of the anterior mediastinum: a clinicopathologicand immunohistochemical study of 9 cases. Hum Pathol 41:17111717. doi:10.1016/j.humpath.2010.05.003

218. White W, Shiu MH, Rosenblum MK, Erlandson RA, WoodruffJM (1990) Cellular schwannoma. A clinicopathologic study of 57patients and 58 tumors. Cancer 66:12661275

219. Wick MR, Rosai J (1991) Neuroendocrine neoplasms of the me-diastinum. Semin Diagn Pathol 8:3551

220. Wilken JJ, Meier FA, Kornstein MJ (2000) Kaposiformhemangioendothelioma of the thymus. Arch Pathol Lab Med124 : 1 5 4 2 154 4 . d o i : 1 0 . 1 0 4 3 / 0 0 0 3 - 9 9 8 5 ( 2 0 0 0 )1242.0.CO;2

221. Wilson H (1941) Extraskeletal ossifying tumors. Ann Surg 113:95112

222. Wilson RW, Moran CA (1998) Primary ependymoma of the me-diastinum: a clinicopathologic study of three cases. Ann DiagnPathol 2:293300

223. Woodruff JM, Godwin TA, Erlandson RA, Susin M, Martini N(1981) Cellular schwannoma: a variety of schwannoma some-times mistaken for a malignant tumor. Am J Surg Pathol 5:733744

224. Yanagawa N, Sasou S, Sato T, Shiono S, Kato H (2006)Mediastinal granular cell tumor: report of a case. Kyobu Geka59:418421

225. Yasuda A, Mizuno A, Mishima A, Sasaki S, Ochi N, Wakasugi T,Sawai H, Takeyama H, Manabe T (2007) Posterior mediastinalangioleiomyoma: report of a case. J Thorac Imaging 22:363365. doi:10.1097/RTI.0b013e31813fabb5

226. Yasui N, Koh K, Kato M, Park MJ, Tomizawa D, Oshima K,Uchisaka N, Gocho Y, Arakawa A, Seki M, Oguma E,Kishimoto H, Watanabe S, Kikuchi A, Hanada R (2013)Kasabach-Merritt phenomenon: a report of 11 cases from a singleinstitution. J Pediatr Hematol Oncol 35:554558. doi:10.1097/MPH.0b013e318281558e

227. Yazici U, Gulhan E, Yazici U, Yaran P, Cakir E, Tastepe I (2011) Acase of giant mediastinal leiomyoma. Turk J Gastroenterol 22:656657

228. Younker D, Boozalis JE (1991) A thoracic leiomyosarcoma pro-ducing tracheal obstruction. J Clin Anesth 3:344346

229. Yousem SA, Hochholzer L (1987) Unusual thoracic manifesta-tions of epithelioid hemangioendothelioma. Arch Pathol LabMed 111:459463

230. Zehani A, Ayadi-Kaddour A, Daghfous H, Ridene I, Marghli A,Kilani T, El Mezni F (2011) Primary mediastinal sarcomas. RevMal Respir 28:1424. doi:10.1016/j.rmr.2010.05.015

231. Zhang WD, Zhao LL, Huang XB, Cai PQ, Xu GX (2010)Computed tomography imaging of anterior and middle mediasti-nal Ewing sarcoma/primitive neuroectodermal tumors. J ThoracImaging 25:168172. doi:10.1097/RTI.0b013e3181a99117

232. Zisis C, Fragoulis S, Rontogianni D, Stratakos G, Bellenis I (2006)Malignant triton tumour of the anterior mediastinum as incidentalfinding. Monaldi Arch Chest Dis 65:222224

233. Zolota V, Tzelepi V, Charoulis N, Apostolakis E, Dougenis D(2006) Mediastinal rhabdomyoma: case report and review of theliterature. Virchows Arch 449:124128. doi:10.1007/s00428-006-0211-8

234. Zukerberg LR, Nickoloff BJ, Weiss SW (1993) Kaposiformhemangioendothelioma of infancy and childhood. An aggressiveneoplasm associated with Kasabach-Merritt syndrome andlymphangiomatosis. Am J Surg Pathol 17:321328

Virchows Arch

Mesenchymal tumours of the mediastinumpart IIAbstractIntroductionSmooth muscle tumours

Pericytic (perivascular) tumoursSkeletal muscle tumoursVascular tumoursBenign and intermediate-grade vascular tumoursMalignant vascular tumours

Chondro-osseous tumoursEwing sarcoma/primitive neuroectodermal tumour (PNET)

Nerve sheath tumours and tumours derived from the autonomic nervous systemTumours of uncertain differentiationAngiomatoid fibrous histiocytomaOssifying fibromyxoid tumourMyoepithelial tumours including parachordomaSynovial sarcomaEpithelioid sarcomaAlveolar soft part sarcoma (ASPS)Clear cell sarcoma of soft tissueExtraskeletal myxoid chondrosarcomaExtrarenal rhabdoid tumourPEComaDesmoplastic small round cell tumourUnclassified/undifferentiated sarcoma

References