Proximal-type epithelioid sarcoma: case report and result of comparative genomic hybridization

Background: Epithelioid sarcoma is a rare mesenchymal neoplasm. Recently, a more aggressive, so-called 'proximal type' epithelioid sarcoma has been described. Clinical case: A 40-year-old-woman presented with 5 x 4 cm, erythematous, indurated, non-movable, painful mass on the pubic area. Histopathology demonstrated diffuse tumor-cell infiltration into the subcutaneous and fascia, which was consisted of prominent epithelioid cells and scattered rhabdoid cells. A multinodular growth pattern or granulomatous appearance with central necrosis was not observed. The tumor cells showed positive reactions for vimentin, cytokeratin (AE1/AE3), and CD34. Despite the surgery, left inguinal mass with lymphadenopathy occurred one month later. We also carried out comparative genomic hybridization (CGH) with tumor cells. CGH revealed chromosomal gain of 5q32-qter, 12q24-qter, and 22q. Conclusion: We report a case of proximal-type of epithelioid sarcoma, which showed the chromosomal gains of 5q32-qter, 12q24-qter, and 22q by CGH.