ORAL EPITHELIOID RHABDOMYOSARCOMA: REPORT OF A RARE CASE

Abstract

Epithelioid rhabdomyosarcoma is a recently proposed variant seen predominantly in adults, and has not been described in the oral cavity. A 33-year-old male patient was referred with a gingival nodule adjacent to the left maxillary canine, with 3 months of evolution. The clinical diagnosis was pyogenic granuloma. Microscopically, there were pleomorphic cells with wide and eosinophilic cytoplasm and eccentric nucleus, resembling a rhabdoid aspect. The cells often exhibited polygonal aspect, like epithelioid cells. In addition, the tumor cells were positive for vimentin, desmin, and MYO-D1. About 50% of the cells were positive for Ki-67. The final diagnosis was epithelioid rhabdomyosarcoma. The patient was submitted to chemo- and radiotherapy, which caused partial regression of the tumor. Wide surgical excision was subsequently performed. After surgery, the tumor recurred and additional resection was executed. Currently, the patient is under follow-up. In summary, epithelioid rhabdomyosarcoma is a rare and aggressive variant in which prognosis is obscure.