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“Not another one!” Making sense of CT and MR imaging features of focal splenic masses
Sara Smolinski1 MD, Michael Morrow1 DO, Qiqing Ge1 MD, Shirley McCarthy2 MD, Alena Kreychman1 MD, and Dmitry Rakita1 MD 1Baystate Medical Center, 2Yale New Haven Hospital
References 1. Abbot RM, et al. Primary Vascular Neoplasms of the Spleen: Radiologic-Pathologic Correlation. Radiographics 2004; 24:1137-1163.
2. Ahmed S, et al. Splenic Incidentalomas. Radiol Clin N Am. 2011;49: 323-47.
3. Ekeh AP, et al. The prevalence of incidental findings on abdominal computed tomography scans of trauma patients. J Emerg Med 2010;38(4):484–9.
4. Lam KY et al. Metastatic tumors of the spleen. A 25-year clinicopathologic study. Arch Pathol Lab Med. 2000; 124:526-530.
5. Levy AD, et al. Littoral cell angioma of the spleen: CT features with clinicopathologic comparison. Radiology 2004; 230:485–490.
6. Luna A, Ribes R, et al. MRI of Focal Splenic Lesions Without and With Dynamic Gadolinium Enhancement. AJR 2006; 186:1533-1547.
7. Paluska TR, et al. Incidental CT findings in trauma patients: incidence and implications for care of the injured. J Trauma 2007;62:157–61.
8. Warshauer DM, et al . Imaging Manifestations of Abdominal Sarcoidosis. AJR 2004; 182:15-28.
The majority of splenic lesions are incidentally detected on routine abdominal CT, typically
performed for other indications. In an emergency room population being scanned for abdominal
pain or trauma, incidental splenic lesions were seen in approximately 1% of patients and the vast
majority of these were considered clinically benign.3,4 It is important to combine clinical factors
with imaging findings for the most accurate evaluation. Relevant findings include abdominal pain,
signs or symptoms of infection, immune status, history of malignancy, associated imaging
findings or history of abdominal trauma. In this poster, we review the most common splenic
lesions encountered and propose an algorithm for their diagnosis and management.
Incidental Splenic Lesions Splenic Cyst “True” congenital or parasitic cysts (20%) possess an epithelial lining. Pseudocysts (80%),
are posttraumatic without an epithelial lining. Typically asymptomatic, cysts may enlarge or
hemorrhage, causing pain or may be the sequela of prior trauma.1,2
images demonstrate a uniformly T2 hyperintense, non enhancing mass. The lesion was resected
for symptomatic relief. Histology demonstrated a congenital cyst with stratified squamous epithelial
wall.
Hemangioma Composed of a proliferation of vascular channels, ranging from capillary to cavernous. Most
commonly singular but may be multiple. Typically asymptomatic. Multiple hemangiomas are
associated with Klippel-Trenaunay-Weber syndrome or Kasabach-Merritt syndrome.1,2
Figure 2. 44 year old male with history of melanoma found to have an enhancing splenic
mass on a contrast enhanced staging CT (a). (b) SSFSE image demonstrates a T2
hyperintense mass. (c-e) T1 fat suppressed GRE images obtained pre, immediately and 1 minute
post contrast administration demonstrate a T1 hypointense mass with initial peripheral and
subsequent homogeneous enhancement, consistent with a splenic hemangioma. Follow up
imaging demonstrated one year stability.
Hamartoma Composed of a disorganized vascular channels and fibrotic red or white pulp elements. Most
are asymptomatic, although may present with pain, palpable mass or rupture if large.
Associated with tuberous sclerosis and Wiskott-Aldrich-like syndrome.1,2
upper abdominal pain. (a) SSFSE image demonstrates a homogeneous, mildly T2 hyperintense
splenic mass which creates a contour abnormality. (b) On the T1 GRE opposed phase image the
mass is isointense to the spleen (c-d) Multiphase subtraction post contrast GRE images
demonstrates progressive homogeneous enhancement. Interval growth of the mass led to
resection and a histological diagnosis of hamartoma.
Littoral Cell Angioma Rare vascular splenic neoplasm arising from littoral cells, which line the splenic red pulp
sinuses and are believed to play a role in the immune response. May be asymptomatic or
can present with abdominal pain, splenomegaly, anemia, thrombocytopenia and
constitutional symptoms. Typically benign but rare reports of malignant behavior, including
metastasis. May be solitary or numerous.1,2,6
mass isointense to normal splenic parenchyma. (b) Fat suppressed non contrast GRE image
demonstrates the mass to be hypointense to isointense to the spleen. (c) Multiphase post contrast
subtraction GRE images demonstrate initial hypointensity with progression to isointensity on the
equilibrium phase (d). Growth led to resection and a histological diagnosis of littoral cell angioma.
Infection
Lymphangioma
Sarcoidosis
Most commonly seen with concurrent hepatic abscesses and sepsis. Fungal microabscesses most common, in an
immunocompromised patient. Tuberculosis typically presents as coalescing micronodules or wedge shaped
peripheral septic emboli.1,2
a b c
Figure 7. 48 year old female with abdominal pain and fever. (a-b) Multiple
ill-defined T1 hypointense and T2 hyperintense intrasplenic and subcapsular
fluid collections consistent with abscesses. (c) CT imaging reveals multiple
subcapsular fluid collections with smaller intraparenchymal fluid collections. (d)
SSFSE image demonstrates a concurrent fluid collection in the liver. Fluid
aspirate grew Streptococcus intermedius.
Figure 8.
40 year old
immuno-
compromised
female with
fever and
abdominal pain.
Congenital abnormality of lymphatic tissue. May be capillary, cavernous or cystic. May be
solitary, scattered or diffuse. Typically asymptomatic, however may present with abdominal
pain, hemorrhage or thrombocytopenia.1,2
Lymphoma Most commonly presents as part of systemic disease, less commonly as primary splenic lymphoma. May present
as multiple nodules, heterogeneous infiltration or diffuse splenomegaly. Often with accompanying retroperitoneal
lymphadenopathy.2
Figure 11. 34 year old male
with pancytopenia. Contrast
enhanced CT demonstrates
diffuse enlargement and
heterogeneous attenuation of
the spleen. The patient
underwent splenectomy for
pain and thrombocytopenia.
Histology demonstrated
marginal zone lymphoma.
Figure 12. 56 year old
female with with
abdominal pain. Contrast
enhanced CT demonstrates
splenomegaly with
innumberable
hypoattenuating nodules
and retroperitoneal
lymphadenopathy. Lymph
node biopsy demonstrated
Hodgkin lymphoma.
Typically presents with multiple non-caseating granulomas on histology. Only 10% of patients present with solely
extra- pulmonary findings. May be associated with liver involvement and thoracic and abdominal lymphadenopathy.
Most patients with splenic involvement are asymptomatic, although hypercalcemia may be present. 2,5,8
a b c
Intense and heterogeneous enhancement
Heterogeneous Heterogeneous Angiosarcoma
Hypointense on immediate postcontrast images, occasionally rim-enhancing intense and heterogeneous enhancement
Hyperintense Hypo - Isointense
Metastases
Hypointense immediately after contrast administration, then isointense on delayed
Hypointense Isointense Lymphoma
Peripheral enhancement when encapsulated; septations may enhance
Hyperintense Hypo - Isointense
Infection
Minimal peripheral enhancement on delayed Hypointense Hypointense Sarcoidosis
Homogeneous progressive enhancement Variable Hypointense Littoral Cell Angioma
No internal enhancement; peripheral enhancement in cystic forms; progressive septal in cavernous and capillary forms
Hyperintense Hypointense Lymphangioma
Heterogeneously diffusely enhancing on early imaging, isointense or hyperintense on delayed
Hyperintense Isointense Hamartoma
Homogeneous brisk or progressive mottled enhancement
Hyperintense Hypointense Hemangioma
No enhancement Hyperintense Hypointense Cyst
Enhancement Pattern T2 T1 Pathology
Common MRI Characteristics Metastases
Only 3% of metastases are to the spleen. Occurs late in the disease, with concurrent involvement of other organs.
Most common sources are breast, lung, and melanoma.4
Figure 13. 60 year old
female with history of
breast cancer. Contrast
enhanced CT
demonstrates diffuse
hypoattenuating nodules
throughout the spleen.
Figure 14. 64 year old male with
history of lung cancer. Contrast
enhanced CT demonstrates
innumerable heterogeneous
hypoattenuating nodules throughout
the spleen and liver with an area of
necrosis in the largest splenic
metastasis.
a b c d
a b c d
a b c d
a b c d
b c d e a
circumscribed largely hypoattenuating mass in the anterior spleen. (b) SSFSE image
demonstrates a hyperintense mass with hypointense septae. (c) Noncontrast fat-suppressed GRE
image demonstrates a hypointense mass. (d) Septal enhancement is demonstrated on an image
obtained 5 minutes post contrast administration. Histology was consistent with lymphangioma.
(a) Innumerable hypoattenuating nodules throughout the spleen on a contrast enhanced CT. (b-c) SSFSE and fat
suppressed noncontrast GRE images demonstrate innumerable hypointense nodules. The nodules demonstrate mild
peripheral enhancement without internal enhancement, as seen on a post contrast axial GRE image (d) consistent with
sarcoid granuloma.
Splenic Mass(es) on CT
Symptoms +/-
Other organ involvement +/-
Abnormal lab values
Asymptomatic Pain attributable
to the spleen
Simple Cyst(s)
Differential, with typical clinical
findings:
- Sarcoidosis (Hypercalcemia)
- Lymphoma (Bulky lymphadenopathy)
- Infection (Sepsis)
- Metastases or metastatic primary
splenic angiosarcoma (Other organs)
Rarely symptomatic benign
neoplasms:
- Hamartoma
- Hemangioma
- Lymphangioma
- Littoral cell angioma
(All listed here may present with
thrombocytopenia or anemia, littoral
cell angioma may present with fever
and constitutional symptoms)
MRI
Indeterminate Solid Mass
Differential:
- Hamartoma
- Lymphangioma
- Littoral cell angioma
- Odds of asymptomatic
angiosarcoma
exceedingly small
Surgical consult,
MRI if further
characterization
warranted
Classic hemangioma
or hemorrhagic cyst
Imaging follow up in 6-12 months
to assess for growth
Differential:
- Lymphangioma
- Littoral cell angioma
- Large benign mass or cyst with
recent hemorrhage causing capsular
stretching
Differential:
- Pseudocyst
- Congenital cyst
- Echinococcus (very
rare, laboratory evidence)
No follow up imaging
No follow up imaging
Further imaging may
not be necessary
Figure 1. 14 year old female with
upper abdominal pain and a large
splenic cyst. (a) Contrast enhanced CT
demonstrates a fluid attenuation mass.
MRI performed 1 year later when patient
developed pain. (b-c) T2 fat-saturated
FSE and post contrast fat-saturated GRE
Figure 6. 55 year old
female with elevated
liver enzymes and a
history of sarcoidosis,
diagnosed by lymph
node biopsy
Angiosarcoma Consists of disorganized vascular channels. Rare and aggressive, presenting with diffuse metastasis to liver, lung,
bone, and lymphatic system. May present with abdominal pain, fever, fatigue, weight loss, anemia,
thrombocytopenia, or coagulopathy. High risk of spontaneous rupture.1,2,6
nodule in the spleen. Heterogeneity is consistent with internal
hemorrhage. (b) Fat suppressed non contrast GRE image
demonstrates a mixed signal intensity nodule in the spleen,
related to presence of internal hemorrhage. Two other similar
appearing nodules were noted in the spleen (not shown).
Figure 16. 43 year old
male with abdominal
pain and hypotension,
related to spontaneous
rupture of a metastatic
splenic angiosarcoma. a b Contrast enhanced CT image demonstrates
heterogeneous masses in the liver and spleen with
hemoperitoneum (Images courtesy of Barak
Friedman MD, NSLIJ, NY)
Figure 15. 81 year
old female with
epigastric pain. (a)
Fat suppressed T2
FSE demonstrates
a mixed signal
intensity exophytic
Figure 3. 46
year old
female with
ulcerative
colitis and
Figure 4. 48 year old
female with an
incidental splenic
mass on CT. (a)
Contrast enhanced
CT demonstrates a
Figure 5. 37 year old
female with history
of ulcerative colitis
and sclerosing
cholangitis. (a) SSFE
demonstrates a
Contrast enhanced CT
demonstrates numerous
hypoattenuating foci in the liver and
spleen, a typical imaging
presentation of fungal
microabscesses. Blood cultures
were positive for Candida albicans.
d
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