Published online Nov 10, 2018. doi: 10.5306/wjco.v9.i7.162
Peer-review started: July 6, 2018
First decision: August 21, 2018
Revised: August 12, 2018
Accepted: October 23, 2018
Article in press: October 23, 2018
Published online: November 10, 2018
A 42-years-old lady, presented with a large retroperitoneal mass which was preoperatively diagnosed as a retroperitoneal liposarcoma following an image guided core biopsy. She underwent a margin-negative resection of the retroperitoneal mass (multi visceral resection - enbloc excision of the retroperitoneal mass with a left nephrectomy and a segmental descending colectomy). The final histopathological examination of the resected specimen confirmed an exophytic renal angiomyolipoma (AML) which was extending into the retroperitoneum. AML is a rare benign tumor arising most commonly from the kidney. It can sometimes present as a diagnostic challenge as it mimics a retroperitoneal liposarcoma or a fat-containing renal cell carcinomas closely. We present this case to share our experience of managing a case of giant exophytic AML which resembled retroperitoneal liposarcoma closely and resulted into an aggressive surgery.
Core tip: A giant exophytic renal angiomyolipoma (AML) can pose a serious diagnostic challenge and may be confused with a retroperitoneal sarcoma. A discordance of the radiological and core biopsy findings in a suspected case of an exophytic renal AML must lead to re-evaluation of the case and repeat biopsies may further clarify the diagnosis.