Renal Cellular Angiofibroma with Retinoblastoma Protein Deletion

Cellular angiofibroma is a benign mesenchymal tumor that is typically found in the vulvovaginal region of women and the inguinoscrotal region of men. Although rare, it can also occur in extra-pelvic locations. This is a unique case report of a 43-year-old premenopausal woman with a cellular angiofibroma located in the right kidney. Pathological examination of the excised mass revealed a well-circumscribed tumor composed of bland spindle cells and variably sized, prominent hyalinized vessels. Immunohistochemical analysis confirmed positive expression of actin alpha 2, desmin, progesterone receptor, and estrogen receptor. Additionally, fluorescence in situ hybridization analysis demonstrated retinoblastoma protein transcriptional corepressor 1 (RB1) loss, which aligns with the diagnosis of cellular angiofibroma. This intriguing case report, along with our review of the existing literature, emphasizes the necessity for further investigation into the pathogenesis of cellular angiofibroma and contributes to the limited knowledge regarding its occurrence in various organs.