Case Report

Year : 2019 | Volume : 2 | Issue : 1 | Page : 9-11

A case of well‐differentiated liposarcoma of the larynx histologically indistinguishable from spindle cell lipoma

Mark Evans, Di Lu, Sunil Verma1, Wamda Goreal

Departments of Pathology and Laboratory Medicine and 1 Otolaryngology, University of California, Irvine, California, USA

Address for correspondence:

Dr. Mark Evans, 101 The City Drive South, Building 1 Room 3003, Orange, California 92868, USA.

E‐mail: evansmg@uci.edu

Abstract

Correctly identifying atypical lipomatous tumors/well-differentiated liposarcomas(WDLs) can be exceedingly difficult, as they account for <0.5% of all laryngeal neoplasms. Diagnosis is further complicated by their morphologic similarity with other more benign lipogenic tumors, such as spindle cell lipoma. We describe a 63-year-old Caucasian man who presented with a left aryepiglottic mass clinically suspicious for a simple cyst. On excision, a frozen section diagnosis of benign fibrolipomatous lesion was reported. Permanent sections revealed an adipocytic neoplasm comprising cellular fibrosis and monomorphic spindle cells, histologically suggestive of a spindle cell/pleomorphic lipoma. Immunostains were positive for CD34 and negative for smooth muscle actin, desmin, and S-100 protein, also consistent with spindle cell/pleomorphic lipoma. However, amplification of MDM2 by fluorescence in situ hybridization confirmed the diagnosis of WDL. The case was reviewed by two soft-tissue pathologists, and they both favored the diagnosis of spindle cell lipoma until reviewing the relevant MDM2 result. The morphology and immunophenotype of WDL have previously been reported as closely related to that of spindle cell lipoma, and this case provides a striking example of how unmistakable these two entities can be on histologic examination alone.

Keywords: Atypical lipomatous tumor/well-differentiated liposarcoma, larynx, MDM2 gene amplification, spindle cell lipoma

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

How to cite this article: Evans M, Lu D, Verma S, Goreal W. A case of well-differentiated liposarcoma of the larynx histologically indistinguishable from spindle cell lipoma. Int J Head Neck Pathol 2019;2:9-11.