Rare extraskeletal Ewing's sarcoma mimicking as adenocarcinoma of the sigmoid.

INTRODUCTION

Extraskeletal Ewing's sarcoma (EES) is a rare finding in comparison with Ewing's sarcoma of bone and usually manifests in young patients. However, even in older patients, one must consider the diagnosis.

PATIENTS AND METHODS

In this case, we describe a 52-year-old woman diagnosed with EES, mimicking as adenocarcinoma of the sigmoid.

RESULTS

The tumor was not visualized by a multi-slice spiral computed tomography of the abdomen and pelvis with intravenous contrast, and eventually the diagnosis was made by positive immunohistochemical staining for CD99 and by molecular testing for EWSR1 translocation.

CONCLUSIONS

This combination of the patient's age and the localization of the tumor mimicking an adenocarcinoma of the sigmoid has never been described before.