A CASE OF MULTIPLE INTRAMUCOSAL SQUAMOUS CELL CARCINOMAS AT THE ANAL CANAL DIAGNOSED BY MAGNIFYING ENDOSCOPY WITH NARROW BAND IMAGING AND EN BLOC RESECTION OF THE LESIONS BY ENDOSCOPIC SUBMUCOSAL DISSECTION

Abstract

A female in her 60s underwent screening colonoscopic examination. Colonoscopy showed an elevated reddish lesion and a small reddish area at the anal canal. Magnifying endoscopy with narrow band imaging (ME-NBI) of the elevated lesion and the small reddish area revealed microvessels similar to the irregular intra-epithelial papillary capillary loops (IPCL) that are observed in superficial esophageal squamous cell carcinoma. These vessels are generally equivalent to type B1 vessel in the Magnifying Endoscopy Classification of the Japan Esophageal Society. We diagnosed the lesions as multiple intramucosal cancer, and endoscopic submucosal dissection (ESD) was performed for en bloc resection. The pathological diagnosis of both lesions was squamous cell carcinoma, pTis, INFa, Ly0, V0, HM0, VM0, ER0.

In this case, we demonstrated that ME-NBI was useful for diagnosis of multiple intramucosal squamous cell carcinoma at the anal canal. In addition, en bloc resection of the lesions by ESD was useful for pathological evaluation.