Epithelioid angiomyolipoma presenting as an urothelial carcinoma of renal pelvis

OBJECTIVE: Renal angiomyolipoma is a mesenchymal neoplasm composed ofdysmorphic blood vessels, smooth muscle, and adipose tissue. Epithelial dangiomyolipoma is an uncommon variant considered potentially malignant. Wereport a case of renal epithelioid angiomyolipoma suspicious for urothelialcarcinoma of renal pelvis. METHODS: A 50-year-old woman with a 3-day history of macroscopic hematuria and CT-scan showing a tumor arising from the left renal pelvis suspicious for urothelialcarcinoma. Nephrectomy was analysed in multiple slides of hematoxilin-eosinand immunohistochemistry. RESULTS: Left nephrectomy was performed. Tumor sized 8cm and showed pathologic findings of epithelioid angiomyolipoma with a little component of classic angiomyolipoma. We studied differential diagnosis and pathologic characteristics for the prognosis. CONCLUSIONS: Pathologic study in detail is fundamental for differential diagnosisand prognosis of this tumor. Our patient'spathology showed good prognosis, however follow-up is important due the malignant potential of the neoplasm.