Extensive intra-abdominal-retroperitoneal fat necrosis in a patient with renal cell carcinoma

Extensive intra-abdominal-retroperitoneal fat necrosis is rare, especially its occurrence in cases of renal cell carcinoma (RCC). We report a patient who presented with a palpable left lower abdominal mass. The RCC was an incidental radiographic finding. The fat necrosis exhibited properties similar to a liposarcoma at laparotomy and on histologic examination of frozen tissue sections. Debulking surgery with left hemicolectomy, transverse colostomy and a midrectal Hartmann pouch was performed. In subsequent surgery, radical right nephrectomy and closure of the colostomy were performed. There were no discernible factors predisposing this patient to fat necrosis. To our knowledge, such extensive intra-abdominal-retroperitoneal fat necrosis is extremely rare. A literature search failed to find a similar case of intra-abdominal or retroperitoneal fat necrosis in association with RCC.