Fine-needle aspiration cytology of "proximal-type" epithelioid sarcoma.

The cytologic and immunocytologic findings in a case of recurrent "proximal-type" epithelioid sarcoma (ES) of the vulva are presented. This is a recently described neoplasm that differs clinically and morphologically from conventional ES. Cytologic smears showed a dissociated population of large, atypical neoplastic cells with bi- and multinucleated cells, abundant cytoplasm, and rhabdoid-like morphology. Due to its different clinical management it must be differentiated from metastatic carcinoma and melanoma. From a practical perspective, its differentiation from other epithelial-like sarcomas is less important. In conclusion the cytopathologic findings of "proximal-type" ES show a good correlation with histopathology, permitting the diagnosis of recurrences and metastases. When accompanied by adequate clinical information and ancillary studies, a specific preoperative recognition seems possible.