Sinonasal perivascular epithelioid cell tumor: Benign or malignant neoplasm?

Abstract

Neoplasms showing perivascular epithelioid cell differentiation (PEComas) are uncommon tumors of the sinonasal tract. They are often misdiagnosed as angiomyolipoma or a simple benign tumor or polyp. We present a further case of a sinonasal PEComa and review the literature in an attempt to ascertain their malignant potential. Published evidence on invasiveness and characteristics were defined on systematic review. MEDLINE and EMBASE were searched from 1966 and 1980, respectively, to week 3 of December 2010. Publications reporting PEComa or angiomyolipoma were sought. Only those describing a sinonasal origin were included. Demographics, anatomic site, local invasion, recurrence rates, and mortality were recorded. A case report of a locally invasive intranasal PEComa is described. In addition to the case we present, 12 case reports were located (n = 13). The mean age of patients was 59.6 (SD, 14.98 years) years. The location was within the right sinonasal tract in 54% of cases, the left sinonasal tract in 38% of cases, and not reported in 8% of cases. Treatment focused on local surgical excision and this was achieved endoscopically in 100% of cases. Recurrence rate was 8%. Mean follow-up was 17.4 (SD, 20.68 months) months. Invasion was noted in 23% of cases. There was a single death recorded. PEComas of the paranasal sinuses and skull base appear to have a biological behavior different from simple benign angiomyolipomas reported elsewhere in the body. PEComa may be more intermediate or malignant in clinical behavior.