# Intraoral Inflammatory Leiomyosarcoma: A Case Report and Literature Review

## TL;DR

This paper reports the first case of inflammatory leiomyosarcoma in the oral cavity, a rare cancer that should be considered in similar diagnoses.

## Contribution

The first documented case of inflammatory leiomyosarcoma occurring in the intraoral region.

## Key findings

- The tumor was composed of spindle-shaped cells with specific immunohistochemical markers like desmin, SMA, and MYOD1.
- The case highlights the importance of including inflammatory leiomyosarcoma in the differential diagnosis of spindle cell lesions with inflammatory infiltration.

## Abstract

Inflammatory leiomyosarcoma (ILMS) is a rare malignant soft tissue neoplasm with smooth muscle differentiation, prominent inflammatory infiltration, and near-haploidization. It is extremely rare in the head and neck region, and no intraoral cases have been reported.

The lesion was initially diagnosed as a malignant spindle cell neoplasm at the referring laboratory. Microscopic examination of blocks of excised fragmented lesion revealed a cellular neoplasm composed of plump, spindle-shaped cells with blunt-ended and elongated nuclei and eosinophilic fibrillary cytoplasm arranged in a fascicular, herringbone to haphazard pattern. The tumor cells were interspersed with mixed inflammatory infiltration and were diffusely positive to desmin, SMA, H Caldesmon, and MYOD1. The diagnosis came as Inflammatory leiomyosarcoma.

This case is the first reported case of ILMS involving the oral cavity. Even though this lesion is very rare, this neoplasm should be included in the differential diagnosis of a spindle cell lesion with marked lymphohistiocytic infiltration.