Extrapelvic Metastases in Endometrial Stromal Sarcomas: A Clinicopathological Review With Immunohistochemical and Molecular Characterization.

Endometrial stromal sarcoma is a rare uterine tumor associated with favorable outcomes despite its ability to recur and metastasize to distant sites. Most recurrences are local, being limited to the abdomen/pelvis, but distant metastases can occur. Metastatic endometrial stromal sarcoma can occur many months to years after the original diagnosis or may present prior to the primary, potentially creating a diagnostic challenge. We report a bi-institutional review of 10 cases of endometrial stromal sarcoma with extrapelvic metastases without a prior history of endometriosis. The histologic, immunophenotypic, and molecular characteristics of these tumors are analyzed in the context of a relevant literature review.