Biphenotypic Sinonasal Sarcoma: A Case Report and Review of Literature

Objectives: Biphenotypic sinonasal sarcoma (BSNS), previously low-grade sinonasal sarcoma with neural and myogenic features, is a rare tumor of the sinonasal tract first described in 2012. Due to its rarity, limited literature is available in providing clinicians with a standardized treatment regimen, particularly in cases of positive surgical margins. This article aims to provide a clinical review of the currently available reported cases of BSNS, as well as presenting clinical, radiologic, and pathologic details of 2 novel cases. Methods: Online electronic databases include PubMed and Embase where queried for reports of biphenotypic sinonasal sarcoma or low-grade sinonasal sarcoma with neural and myogenic features. Two previously unpublished cases were included in the results. Data including clinical presentation, epidemiologic data, radiologic evaluation, intraoperative details, histopathology, treatment modality, and postoperative follow-up information were included. Results: A total of 100 previously published cases were identified in 12 prior articles. Mean age at presentation was 52.9 years. Extrasinonasal extension was observed in 27.4% of cases with most common site of extension being cribriform plate. Forty-seven cases included treatment details with surgical excision being the most common modality. Recurrence rates were identical for both surgical excision alone and surgical excision with adjuvant radiotherapy (33.3%). Conclusions: Biphenotypic sinonasal sarcoma is a slow-growing tumor that is amenable to surgical resection. Recurrence rates are similar between surgical excision and surgical excision with adjuvant radiation therapy, but limited data in reported cases preclude a determination of treatment superiority.