Giant retroperitoneal lipoma presenting as abdominal protrusion: One case report and review of literature

Lipomas are benign tumors of mature adipocytes, which are commonly located in the subdermal tissue of the trunk or extremities. Deep‐seated lipomas, especially originating from the retroperitoneal space, are extremely rare. We present the case of a 57‐year‐old man with a giant retroperitoneal lipoma but without impaired gastrointestinal (GI) function. This patient visited the GI outpatient clinic for progressively distended abdomen in the preceding months. The patient denied experiencing any nausea, loss of appetite, abdominal pain, and change of bowel habits. Physical examination demonstrated a soft, nontender protrusion in the abdomen without guarding. Further analysis via dynamic liver computed tomography scan indicated a large, fat‐attenuated, mass‐like lesion in the left upper abdomen. In order to rule out malignant fat‐containing retroperitoneal masses, the patient underwent resection of the retroperitoneal and intra‐abdominal tumor. It is quite important to analyze the characteristics of the tumor accurately in order to make subsequent decisions on how to proceed with the surgery.