|
|
Diagnosis |
Number of cases |
Imaging characteristics |
Pathological characteristics | Clinical behavior |
| CT | MRI | Histology | Immunohistochemistry + |
|
| Primary adrenal lymphoma [8–15] | <200 | Mostly hypodense tumors, aspect homo- or heterogeneous, slight to moderate contrast enhancement. | Iso/hypointense in T1 and hyperintense in T2. | Atypical cells, anisokaryosis, hyperchromasia, necrosis. | Most common: CD45/CD20/CD40 (B-cell)
CD3/CD30/CD43 (T-cell) | Malignant |
|
| Dedifferentiated liposarcoma [16–22] | >500 | DDLS: nonlipogenic, heterogeneous node within a well-delineated, lipogenic, and septated mass that is the WDLS | WDLS: >75% fat, nonlipomatous components are prominent thick septa. Nodular nonadipose areas may be present.
DDLS within WDLS: low to intermediate on T1 and intermediate to high on T2. | Atypical nonlipogenic stromal cells with hyperchromatic nuclei, scattered in fibrous septa. Cellularity and nuclear atypia increase with dedifferentiation. Mitotic rate typically <8/10HPF. | MDM2, CDK4 | Malignant |
|
| Schwannoma [23–27] | >500 | Round, well-circumscribed, hypo- or iso-intense compared to muscle, enhancement postcontrast. | Intermediate on T1 (isointense to muscle), mared increase on T2. | Elongated spindle cells in areas of both high (Antoni A) and low cellularity (Antoni B). | NSE, microfilament, S100 | Benign |
|
| Ganglioneuroma [28–32] | >60 | Att. > 25 HU, homogeneous aspect, calcifications in 30%–60%. | Hypointense on T1, heterogen. hyperintense on T2. | Ganglion cells, spindle cells, nerve fibres. | NSE, synaptophysin, S100, and CD57. | Benign
Rare: transformation to malignant nerve sheath tumor. |
|
| Idiopathic adrenal haematoma [33–35] | >10 | Variable: homo/heterogeneous depending on lesion’s age. | High intensity on T1 in periphery of lesion suggests hemorrhage. | Hemorrhage, necrosis and hemosiderin. | — | Benign |
|
| Cavernous haemangioma [36–39] | >60 | Heterogeneous, central cystic/necrotic components, calcifications, nodular peripheral enhancement postcontrast. | Homogeneous on T1, high intensity on T2. | Necrosis, cystic components, large vascular spaces, single lining of endothelium. | — | Benign
Risk of spontaneous hemorrhage.
Rare: transformation to angiosarcoma. |
|
| Angiomyolipoma [40–44] | <10 | Heterogeneous: contains fat, possibly small enhancing foci. | — | Adipose tissue, smooth muscle fibres. | HMB45, MART1/MelanA, smooth muscle actin. | Benign
Risk of spontaneous hemorrhage. |
|
| Epithelioid angiosarcoma [45–49] | >20 | Irregular margins, nonhomogeneous density, calcifications. | High intensity on T2. | Vascular spaces lined by endothelial cells with epithelioid features, possibly pleomorphism. | Factor VIII, also CD34 and UEA-1 (less specific). | Malignant |
|
| Leiomyosarcoma [50, 51] | <20 | Heterogeneous, possibly also liquid components. | — | Spindle-shaped neoplastic cells, nuclear pleomorphism, giant cell formation. | Smooth muscle actin. | Malignant |
|
| Cyst [52–57] | >600 | | | | | |
| Pseudocyst | 39% | Fibrous wall, no endothelial/epithelial lining, dependent on age septations, blood products, fluid-fluid level, or soft tissue component. | Intermediate/high density in T1, marked bright up in T2. | Usually unilocular, no endothelium. Contains brown/reddish fluid. Connective tissue walls calcificated/hyalinized. | — | Benign |
| Endothelial | 45% | Thin wall (≤3.5 mm), smooth borders and pure cystic internal structure. Att. < 20 HU. No contrast enhancement. |
— | Smooth endothelial lining, contains clear or milky fluid. | D2-40. | Benign |
| Epithelial | 9% | Lined with cylindrical epithelium. | Calretinin and WT-1. | Benign |
| Parasitic | 7% | Floating membrane or daughter cysts, septal or mural calcifications, coexistent hydatid cysts of other organs. | — | Thick, possibly calcificated walls, parasites within. | — | Benign |
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