新しいmodalityによる大腸拡大観察の有用性・問題点・将来展望―endocytoscopy

Usefulness and Pespective of Endocytoscopy on Colorectal Lesions

要旨　大腸限局性病変および正常粘膜，計75病変をprobe-type endocytoscopeで観察した．当該病変の病理組織結果および内視鏡画像を知らない病理医が，endocytoscopy画像を診断し，最終病理組織診断と対比した．endocytoscopy診断の正診率は93.3％，Kappa valueは0.910であり，病理診断と有意な相関を示した．endocytoscopyによる腫瘍と非腫瘍の鑑別診断能は母集団が少ないが100％，sm以深癌の診断率は感度92.3％，特異度100％であった．最近，通常の拡大内視鏡とendocytoscopyが一体となったscopeが開発された．通常観察，拡大観察，450倍の超拡大観察が1本のscopeで連続的に施行可能となった．今後，さらなる症例の蓄積により，診断能向上への寄与が期待される．

　The subjects were 113 consecutive patients who underwent a complete colonic examination. Endocytoscopic examination was performed on 75 localized colorectal lesions including normal mucosa with a probe-type endocytoscope. The design was prospective. A pathologist, who was blinded to the conventional colonoscopic views and to the final histologic diagnosis, made a diagnosis of the endocytoscopic images by reviewing the digital files of the images. The endocytoscopic diagnosis corresponded well with the final histological diagnosis with a 93.3％ accuracy rate and a kappa value of 0.910. The differential diagnosis between neoplastic and non-neoplastic lesions was 100％ correct. The sensitivity and specificity of the diagnostic ability of endocytoscopy on invasive cancer among the neoplastic lesions were 92.3％ and 100％, respectively.

　Integrated-type endocytoscopy has been developed recently, providing an ordinary view, a magnified view up to ×80, and a highly magnified view of ×450 without any extra equipment. It is expected that the ultra-high magnified views will add more information to conventional magnification and make the diagnosis even more precise.