Extranasopharyngeal angiofibroma mimicking choanal polyp in patients with chronic paranasal sinusitis

Extranasopharyngeal angiofibroma (ENA) is an angiofibroma that occurs in the extranasopharynx. It shows pathologic findings, such as juvenile angiofibroma (JNA), which accounts for 0.5% of head and neck mass. However, compared with JNA, the prevalence, affected site, and clinical characteristics are completely different, which leads some physicians to classify ENA as a disease different from JNA. ENA of the nasal turbinate origin are rarely reported in the literature. In addition, choanal polyp originating from the posterior part of the nasal turbinate is uncommonly reported. Recently, we encountered two cases of ENA, which were not diagnosed by intraoperative frozen section examination, but were histopathologically diagnosed post-operatively. Although we were unable to diagnose and perform embolization pre-operatively, ENA has been successfully treated by endoscopic surgery, without profuse bleeding.