A rare case of abdominal (lesser sac) myxoid liposarcoma: A case report

Myxoid liposarcomas (MLS) are genetically defined by DDIT3 gene fusions and most commonly arise in the extremities. They can also occur in the retroperitoneum as a primary site. However, there are controversies in its occurrence. It peaks in the fourth and fifth decades of life, affecting both gender equally.

A 38-year-old male patient presented with painless abdominal swelling, indigestion, and loss of appetite of 08 months duration. The abdominal examination showed a regular non-tender mass filling the left upper quadrant mimicking huge splenomegaly. An abdominopelvic ultrasound shows a huge echo complex mass filling the left upper abdomen. A contrast CT scan revealed a well-defined mass filling the lesser sac with a moderate mass effect on nearby abdominal organs with a clear fat plane and hence with no sign of invasion. Laboratory tests were found to be in the normal range except moderate anemia. Laparotomy was decided after case analysis and correction of anemia. A huge mass excised from the lesser sac and sent for histology. The patient went home on the third day after laparotomy. Histopathologic results reported retroperitoneal MLS with the classic microscopic findings.

MLS is the second most common type of liposarcoma, and tends to occur in the lower extremities. It rarely occurs in the retroperitoneum, with most cases being classified as atypical lipomatous tumors with prominent myxoid change.

It is crucial to differentiate a metastatic MLS originating from the lower extremities. The principle of treatment is complete surgical resection.