Monotypic epithelioid angiomyolipoma of the adrenal gland: an unusual site for a rare extrarenal tumor.
Epithelioid angiomyolipoma (AML) is an uncommon renal mesenchymal tumor with malignant potential and is frequently associated with tuberous sclerosis. Extrarenal AMLs are rare, and to the best of our knowledge, this is the first reported case of a primary monotypic epithelioid AML of adrenal gland in a patient without evidence of tuberous sclerosis. The patient is a 42-year old man who presented with retroperitoneal hemorrhage resulting from spontaneous rupture of adrenal mass. Histologically, the tumor showed a prominent component of epithelioid smooth muscle cells with slightly pleomorphic nuclei, sometimes with prominent nucleoli and eosinophilic cytoplasm resembling oncocytic tumors. Epithelioid cells were positive for melanoma (HMB45 and positive MelanA) and smooth muscle markers (alpha-smooth muscle-specific actin), but not for epithelial markers (cytokeratin, EMA). Differential diagnosis from renal cell carcinoma, adrenal gland carcinoma, and metastatic carcinoma is often challenging because of its epithelioid morphology. Because primary and secondary malignant tumors are much more common and aggressive neoplasms, establishing the correct diagnosis has important therapeutic and prognostic implications.
D'Antonio
Antonio
A
Department of Pathologic Anatomy, AO San Giovanni di Dio e Ruggi d'Aragona, Salerno, Italy. ada66@inwind.it
Caleo
Alessia
A
Caleo
Oliviero
O
De Dominicis
Gianfranco
G
Boscaino
Amedeo
A
D000230:Adenocarcinoma / Q000175:diagnosis; D000310:Adrenal Gland Neoplasms / Q000737:chemistry / Q000150:complications / Q000473:pathology*; D000315:Adrenalectomy; D000328:Adult; D018207:Angiomyolipoma / Q000737:chemistry / Q000150:complications / Q000473:pathology*; D014408:Biomarkers, Tumor / Q000032:analysis; D002292:Carcinoma, Renal Cell / Q000175:diagnosis; D003937:Diagnosis, Differential; D018572:Disease-Free Survival; D015622:Epithelioid Cells / Q000737:chemistry / Q000473:pathology; D006470:Hemorrhage / Q000209:etiology / Q000473:pathology; D006801:Humans; D008297:Male; D009362:Neoplasm Metastasis; D009392:Nephrectomy; D012187:Retroperitoneal Space / Q000473:pathology; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D014408:Biomarkers, Tumor