Pigmented Renal Epithelioid Angiomyolipoma: A Case Report and Literature Review

Melanin pigmentation in epithelioid angiomyolipoma (AML), a potentially malignant and locally aggressive renal tumor, is an exceptionally rare finding. Accurate differentiation from other pigmented tumors, such as melanoma, pigmented paraganglioma, and pigmented renal cell carcinoma is essential for proper diagnosis and treatment. A retrospective review of 2 departmental archives (2000-2023) identified 2 pigmented renal epithelioid AML specimens. Clinical presentations, histopathological features, immunohistochemical profiles, and molecular findings were analyzed. Both specimens exhibited melanin pigmentation, and 1 tumor demonstrated unique molecular alterations, including TSC2 and TP53 mutations. This study underscores the importance of meticulous histopathological evaluation and molecular profiling in diagnosing and managing this extremely rare variant of epithelioid AML.