# Primary Mesenteric Well-Differentiated Inflammatory Liposarcoma With Mucosal Extension: A Lesion With High Risk for Misdiagnosis

## TL;DR

A rare case of a primary mesenteric liposarcoma with mucosal extension is presented, highlighting the risk of misdiagnosis and the need for careful analysis.

## Contribution

The paper reports a rare case of primary mesenteric well-differentiated inflammatory liposarcoma with mucosal extension.

## Key findings

- Primary mesenteric well-differentiated inflammatory liposarcomas are exceedingly rare.
- Such lesions are at high risk for misdiagnosis, especially when first seen in endoscopic biopsies.
- Accurate diagnosis requires histopathology, immunohistochemistry, and MDM2 amplification testing.

## Abstract

Well-differentiated liposarcomas are common retroperitoneal lesions, but exceedingly rare when primary to the small bowel mesentery, with only a handful of cases reported in the literature. Presented is a patient with a primary mesenteric well-differentiated inflammatory liposarcoma with mucosal extension at high risk for misdiagnosis. A broad differential diagnosis with careful histopathologic observation, ancillary immunohistochemical studies, and fluorescent in situ hybridization for MDM2 amplification are key to make a correct diagnosis. This is especially true if such a lesion was first noted in the lamina propria on histopathology from an endoscopic mucosal biopsy.