Giant exophytic renal angiomyolipoma masquerading as a retroperitoneal liposarcoma: A case report and review of literature

Figure 1 Axial section of contrast enhancement computed tomography abdomen. A: It shows two fairly well defined, predominantly fat density rounded lesions, in the left kidney. The peripheral capsule (arrow) of the smaller lesion is ill defined and continuous with a very large perirenal angiomyolipoma showing prominent vessels (+); B: Sagittal reconstruction shows a peripheral hematoma (arrow) in the perirenal lipomatous mass.

Figure 2 Preoperative core biopsy of tumor mass. A: Variable sized adipocytes (10 ×); B: Variable sized adipocytes with atypia (40 ×).

Figure 3 Resected enbloc specimens of retroperitoneal mass, left kidney, and colon.

Figure 4 Final histopathology of surgical specimen. A: Components of all the three tissues, i.e., mature adipocytes, spindle shaped smooth muscle cells and blood vessel (10 ×); B: Immunohistochemical staining for smooth muscle actin shows strong positivity in final histology specimen.