Intricacy in the Diagnosis of Retroperitoneal Angiomyolipoma: A Rare Case

An uncommon benign mixed mesenchymal tumor called extrarenal retroperitoneal angiomyolipoma (ERAML) comprises thick-walled blood vessels, smooth muscle cells, and mature fat cells. Angiomyolipoma often develops in the kidneys, with extrarenal locations being uncommon. Many angiomyolipomas are unintentionally discovered when a person undergoes other medical issues. A 35-year-old man presented with a history of difficulty breathing and was on antibiotics. On follow-up, CT revealed a 22.5 × 14.3 × 8.6 cm right retroperitoneal mass. The retroperitoneal mass was resected en bloc at laparotomy and sent for histopathological examination. The grossly resected specimen was a smooth, well-circumscribed, yellowish-red retroperitoneal mass measuring 23 × 15 × 9 cm. The microscopic section reveals a tumor with prominent blood vessels and fatty tissue composed of spindle cells arranged into fascicles. The final diagnosis for this case is ERAML, which was challenging to distinguish from liposarcoma.