Real-time histological imaging of a squamous cell carcinoma in situ in the anal canal using endocytoscopy - Utsunomiya, Manami; Tsuji, Shigetsugu; Kawasaki, Azusa; Takemura, Kenichi; Katayanagi, Kazuyoshi; Minato, Hiroshi; Doyama, Hisashi (Endoscopy, 2021)