Literature Review: Cytopathology of Epithelioid Sarcoma

In this study, 20 cases of epithelioid sarcoma (EpS) were identified from a cytopathology and surgical pathology databases. One patient had 5, 1 patient had 3, and 3 patients had 2 separate specimens. Cases included, 7 new, 7 locally recurrent, and 6 with metastases. Site included lower extremity (8 cases), upper extremity (4), trunk (4), serous effusion (2), scalp (1), and mediastinum (1).

Thirteen cases had specific cytologic diagnosis of EpS, 5 of sarcoma not otherwise specified, and 2 as malignant neoplasm. In cases where cell-block SMARCB-1 staining was used, EpS was specifically recognized. Cytomorphology was composed primarily of epithelioid/plasmacytoid cells having eccentrically positioned nuclei, moderate cytoplasm, and variable nuclear pleomorphism.

The authors concluded that, “The cytopathology of EpS is somewhat variable, morphologically non-specific, and mimics that of other neoplasms with epithelioid features. Ancillary immunostaining is necessary for a specific diagnosis in newly encountered patients.”

Reference

Wakely PE Jr. Cytopathology of classic type epithelioid sarcoma: a series of 20 cases and review of the literature [published online ahead of print, 2020 Feb 6]. J Am Soc Cytopathol. 2020;S2213-2945(20)30014-4.