Case Report

Intracranial Rosai-Dorfman Disease with Unusual TranscranialExtension

Chia-Hsing Lu, MD, Kung-Chao Chang, MD, E-Jian Lee, MD, Ming-Tsung Chuang, MD, Ruey-Sheng Chang, MDFrom the Cheng-Kung University Hospital, Department of Diagnostic Radiology, Tainan City, Taiwan (RC, CL, KC, EL, MC).

Keywords: Rosai-Dorfman disease, in-tracranial tumor, dural mass, menin-gioma.

Acceptance: Received April 5, 2010, andin revised form June 20, 2010. Acceptedfor publication July 15, 2010.

Correspondence: Address correspon-dence to Ruey-Sheng Chang, MD,Cheng-Kung University Hospital, Depart-ment of Diagnostic Radiology, No.138,Shengli Road, North District, TainanCity 704, Taiwan, (R.O.C.). E-mail:i5488150@nckualumni.org.tw.

Conflict of Interest: None.

J Neuroimaging 2010;XX:1-4.DOI: 10.1111/j.1552-6569.2010.00539.x

A B S T R A C TA 48-year-old woman presented with a growing palpable mass at the left frontal area. Theimaging studies and histopathological examination of the mass was consistent with dural-based Rosai-Dorfman disease with unusual transcranial extension. We reported this casenot only because of its rarity, but also because of the infiltrative pattern. The infiltrativenature presented in this case may be taken into consideration for surgical treatment ofintracranial Rosai-Dorfman disease.

IntroductionRosai-Dorfman disease (RDD), an idiopathic histiocytic pro-liferation presenting as massive lymphadenopathy, was firstdescribed by Rosai and Dorfman in 1969.1 Extranodal involve-ment of RDD is less common, while isolated intracranial in-volvement of RDD is even rarer, with around 40 cases reportedso far.2 The majority of reported intracranial RDD present assolitary dural-based mass.3 Herein, we present a case of dural-based RDD with microscopic skull involvement and bulky ex-tracranial extension.

Case ReportA 48-year-old woman without a remarkable medical historypresented with a firm but painless mass at the left frontal areafor 18 months. On presentation, she showed no systemic symp-toms. Physical examination and neurological examination re-sults were normal, with no evidence of cervical lymphadenopa-thy. The axial computed tomography (CT) revealed anisodense dural-based mass at the left frontal area with com-pression of the left frontal lobe (Fig 1A). Extracranial extensionof the mass was seen as well. Axial CT images using bonewindow setting (Fig 1B) showed an intact bony cortex. A sub-sequent magnetic resonance imaging (MRI) was arranged anddemonstrated the mass to be isointense on short inversion re-covery (STIR) images and fluid attenuated inversion recovery(FLAIR) images (Fig 2B). The mass was homogeneously en-hanced on postgadolinium (Gd) T1-weighted images (Figs 2C

and D). The intracranial and extracranial portions of the massencased the normal-appearing skull bone. This particular en-hancing pattern made the tumor a “hamburger-like” appear-ance. A preoperatively radiological diagnosis of meningiomawas made.

During surgery, the intracranial portion of the tumor hadwell-defined cleavage plane with underlying brain parenchyma.Total removal of the tumor was achieved, including intracra-nial, extracranial portions, and the attached skull bone. Ongross pathological examination, the extracranial portion of thetumor was firmly attached to the skull bone (Fig 3A). Since thislesion involved extensively both extracranial and intracranialspaces, including dura, it is, thus, difficult to ascertain the ori-gin. However, histopathologic evidence of dural involvementis clearly shown (Fig 3B). The dura and adjacent soft tissueshowed multifocal infiltration of lymphoplasmacytic cells withdense fibrosis. In the inflammatory infiltrates, there were manylarge histiocytes with round nuclear outlines and abundant pale-pink cytoplasm, in which a few lymphocytes were engulfed—aphenomenon called lymphocytophagocytosis or “emperipole-sis” (Fig 3C), characteristic of RDD. Immunohistochemically,these histiocytes were positive for S-100 but negative for acluster of differentiation (CD) 1a (Fig 3D) or epithelial mem-brane antigen (EMA). Acid-fast and Grocott’s MethenamineSilver stains failed to identify any pathogen. The intracranialand extracranial portions of the lesion showed the same his-tological features. The skull bone was also involved in the

Copyright ◦C 2010 by the American Society of Neuroimaging 1

Fig 1. Axial CT (A) revealed an isodense dural-based mass (star) at left frontal area with left frontal white matter edema (arrowheads) andcompressed left frontal lobe. An isodense extracranial soft tissue mass (arrows) is seen. Axial CT image using bone window setting (B) showsintact bony cortex (open arrows) of left frontal bone.

Fig 2. STIR (A) and FLAIR (B) images show isointensity of the left frontal dural-based mass (star), with compressed left frontal lobe andwhite matter edema (arrowheads). An extracranial extension of the mass (arrows) is seen as well. Post-Gd axial (C) and coronal (D) imagesdemonstrate homogeneous enhancement of the dural-based mass and the extracranial portion, but no enhancement of the attached skull.This enhancing pattern gives the tumor a “hamburger-like” appearance.

2 Journal of Neuroimaging Vol XX No XX 2010

Fig 3. Gross specimen (A) of skull bone and extracranial mass consists of a skull bone (6 × 6 cm2) with a well-defined soft tissue mass(5 × 3 × 1.5 cm3) that is pale tan in color and elastic in consistency. The skull bone shows no obvious osteolytic lesion. Microscopically, thedura (B, right upper, 20×) and adjacent soft tissue show multifocal infiltration of chronic inflammation cells with dense fibrosis (inset, 100×). Inthe inflammatory infiltrates, there are many large histiocytes showing abundant pale pink cytoplasm (C, 100×) with lymphocytophagocytosis(also called “emperipolesis”, inset, arrows, 400×), a characteristic feature for RDD. Immunohistochemically, the histiocytes are positive forS-100 (D, left panel, 200×) but negative for CD1a (D, right panel, 200×). The skull bone is also involved by the same lesion (E, 100×), whichis highlighted by S-100 stain (F, 400×).

same lesion (Fig 3E), and highlighted by S-100 stain (Fig 3F).The histopathologic features were consistent with a dural-basedRDD with skull bone and extracranial extension.

The postoperative course was uneventful and the patientwas discharged 5 days later. Eleven months after surgery, aMRI revealed no evidence of recurrence.

DiscussionSince the first report by Foucar in 1982, intracranial RDD is stillpoorly studied due to its rarity. About 80 cases of RDD withintracranial involvement have been reported so far.4 Isolatedintracranial RDD is even rarer, with a total number of around 40cases in the English literature.2 The majority of the intracranialRDD were reported as solitary dural-based masses, but duringlast 10 years, different appearances of intracranial RDD havebeen identified, including multiple dural-based masses, diffuse

leptomeningeal spreading, intraventricular mass, cerebral mass,cerebellar mass,3 intracranial mass with orbital extension,5 anddural-based mass with skull and extracranial invasion in ourcase.

In this case, the initial examination and clinical follow upexcluded lymphadenopathy or other systemic involvement ofRDD. The histopathological examination confirmed identicalcomponents of both intracranial and extracranial portions ofthe mass, as well as lymphohistiocytic infiltration of the encasedskull bone. Microscopically, the lymphohistiocytic infiltrationin the skull bone was multifocal and limited in the intertra-becular space without obvious destruction to bony trabeculae.A possible route for the dural-based RDD to infiltrate the skullbone and extend to extracranial space was through diploic veinsor lymphatic drainage of skull bone. With bulky lymphohisti-ocytic infiltration at both dural and subgaleal sites, the skullinvolvement was not destructive and the bony contour was

Lu et al: Intracranial Rosai-Dorfman Disease 3

retained. This may explain the relatively normal appearance ofthe skull bone with an intriguing “hamburger-like” picture onimage studies.

Radiographic differential diagnosis includes meningioma,Langerhans cell hystiocytosis (LCH), metastasis, granuloma-tous infection, or inflammation. Intracranial RDD can seemidentical to meningioma on image studies and even on surgicalfindings.7 Meningiomas may also present with extracranial ex-tension, with image appearance similar to that of our patient.4

In cases with meningioma en plaques, extracranial extensionis even more often. Although not necessary for the diagnosis,hyperostosis of the skull bone is a well-known sign for menin-gioma en plaque.8 This specific sign is never reported in dural-based RDD, and is absent in our patient. LCH of the headhas variable manifestations. The most often presentations arehypothalamic-pituitary lesions and cranial-facial lesions. Tran-scranial involvement of LCH should present with osteolysis andsoft tissue replacement of the encased skull. There is a predilec-tion of LCH to occur in a multifocal pattern rather than soli-tary.9 Metastatic tumors presented with transcranial invasionare not uncommon. Image evidence of bony structure destruc-tion is expected in metastasis to the skull. Multiplicity of lesionsand the history of primary malignancy are most important forthe diagnosis of metastatic lesions. Infection and granulomatousprocesses sometimes can appear as dural-based solid mass, andcan only be distinguished from other dural-based tumor byhistological study.10,11

Under microscope, the EMA-negative, lymphohistiocyte-rich morphology of RDD can be readily differentiated frommeningioma and metastatic carcinomas. A plasmacytomawould show atypical characteristics, immature cytological fea-tures, and a monotypically light chain phenotype, which areabsent in RDD. A bunch of lymphoproliferative diseases canbe differentiated by the immunohistochemical examination.

While spontaneous regression is observed in more than 50%of systemic RDD,12 there has been no report of this in isolatedintracranial RDD. The treatment is mainly surgical. The courseof isolated intracranial RDD is generally benign, with no reportof recurrence following total excision.7 A few deaths have beenreported, but all of them were considered due to etiologies otherthan intracranial RDD itself.3 Recurrence is expected in par-tially resected lesions. Adjuvant therapy with corticosteroids, ra-diotherapy, and/or chemotherapy has been reported with somesuccess.13,14 We reported this case of RDD not only because ofits rarity, but also because of the infiltrative pattern. The skull

bone showed normal signal on all image studies, but turned outto be infiltrated by RDD. Since relapse is expected followingincomplete resection of RDD,13,14 the extent of surgery shouldbe carefully planned.

References1. Rosai J, Dorfman RF. Sinus histiocytosis with massive lym-

phadenopathy. A newly recognized benign clinicopathological en-tity. Arch Pathol 1969;87(1):63-70.

2. Lungren MP, Petrella JR, Cummings TJ, et al. Isolated intracra-nial Rosai-Dorfman disease in a child. AJNR Am J Neuroradiol2009;30:E148-E149.

3. Gupta DK, Suri A, Mahapatra AK, et al. Intracranial Rosai-Dorfman disease in a child mimicking bilateral giant petroclivalmeningiomas: a case report and review of literature. Childs NervSyst 2006;22(9):1194-1200.

4. Wan S, Teng X, Zhan R, et al. Isolated intracranial Rosai-Dorfmandisease mimicking suprasellar meningioma: case report with reviewof the literature. J Int Med Res 2008;36(5):1134-1139.

5. Scumpia AJ, Frederic JA, Cohen AJ, et al. Isolated intracra-nial Rosai-Dorfman disease with orbital extension. J Clin Neurosci2009;16(8):1108-1109.

6. Buetow MP, Buetow PC, Smirniotopoulos JG, et al. Typical,atypical, and misleading features in meningioma. Radiographics1991;11(6):1087-1106.

7. Kattner KA, Stroink AR, Roth TC, et al. Rosai-Dorfman diseasemimicking parasagittal meningioma: case presentation and reviewof literature. Surg Neurol 2000;53(5):452-457; discussion 457.

8. Akutsu H, Sugita K, Sonobe M, et al. Parasagittal meningioma enplaque with extracranial extension presenting diffuse massive hy-perostosis of the skull. Surg Neurol 2004;61(2):165-169; discussion169.

9. Prayer D, Grois N, Prosch H, et al. MR imaging presentation ofintracranial disease associated with Langerhans cell histiocytosis.AJNR Am J Neuroradiol 2004;25(5):880-891.

10. Chang KH, Han MH, Roh JK, et al. Gd-DTPA-enhanced MRimaging of the brain in patients with meningitis: comparison withCT. AJR Am J Roentgenol 1990;154(4):809-816.

11. Toh CH, Chen YL, Wong HF, et al. Rosai-Dorfman diseasewith dural sinus invasion. Report of two cases. J Neurosurg2005;102(3):550-554.

12. McAlister WH, Herman T, Dehner LP. Sinus histiocytosis withmassive lymphadenopathy (Rosai-Dorfman disease). Pediatr Radiol1990;20(6):425-432.

13. McPherson CM, Brown J, Kim AW, et al. Regression of intracra-nial Rosai-Dorfman disease following corticosteroid therapy. Casereport. J Neurosurg 2006;104(5):840-844.

14. Petzold A, Thom M, Powell M, et al. Relapsing intracranial Rosai-Dorfman disease. J Neurol Neurosurg Psychiatry 2001;71(4):538-541.

4 Journal of Neuroimaging Vol XX No XX 2010