Epithelioid sarcoma, masquerading as sporotrichosis

Epithelioid sarcoma (ES) is a rare soft tissue neoplasm appearing as multiple slow growing skin nodules. It is a locally invasive tumor, but may metastasize to regional lymph nodes and lungs.

A 19 year old male presented with multiple painful skin nodules, with linear distribution on right upper limb for 2 years. Initial histology mimicked fungal infection, but response to antifungal treatment was poor. His last skin biopsy showed nodular tumor in the dermis with central necrosis and cytological atypia. Immunohistochemistry confirmed the diagnosis of ES. Since he had radiological evidence of lung metastases, chemo radiotherapy was given. Out of the two phenotypes of ES, distal type may show a sporotrichoid pattern. Histology may mimic non neoplastic granulomatous dermatoses. Cells are positive for cytokeratins, epithelial membrane antigen, vimentin and CD34.

Diagnosis would be difficult as ES mimics other common non neoplastic granulomatous dermatoses including sporotrichosis.