A Case of Blue Nevus of the Nasal Septum

Abstract

Blue nevus (BN) is a blue- or black-colored benign melanocytic proliferation that commonly occurs on the dorsal surface of the hands and feet or in the head and neck region. However, BN arising from the sinonasal mucosa is extremely rare. BN is usually asymptomatic and small in size. Based on the pigmentation of BN, sinonasal malignant melanoma should be considered in the differential diagnosis of BNs in this region. We herein report a case of BN of the nasal septum. Histopathologic examination revealed the presence of heavily pigmented, spindle-shaped melanocytic cells within the stromal tissue. On immunohistochemical analysis, BN cells were positive for S-100 and HMB-45. Due to the few reported cases of sinonasal BN and challenging location, complete resection, biopsy, and adequate follow-up are recommended.