Imprint cytology of extraskeletal mesenchymal chondrosarcoma of the perineum: a case report

BACKGROUND: Extraskeletal mesenchymal chondrosarcoma (EMC) is an uncommon soft tissue tumor, occurring mainly in the lower limbs, meninges and retroperitoneum. EMC of the female genital tract is extremely rare, and the cytologic literature is scarce. CASE: A 43-year-old female with a growing perineal mass underwent excision of the tumor. Pathologic examination of the rumor revealed a characteristic two-cell pattern of primitive small cells and cartilaginous tissue. A diagnosis of EMC of the perineum was made. Imprint cytology from surgical material showed a cluster of small round cells with a focal hemangiopericytomalike arrangement and islets of cartilage. The cartilaginous cells reacted with S-100 protein immunocytochemically. CONCLUSION: The characteristic features of EMC, a hemangiopericytomalike arrangement of small cells and S-100-positive cartilaginous cells, may be helpful in diagnosing EMC and differentiating it from other perineal tumors.