INTESTINE Vol.18 No.3(1-1)

特集名 今,変わるのか? 大腸微小病変の取り扱い
題名 [総論](1) 微小腫瘍性病変の臨床病理学的特徴─Japan Polyp Study 1次TCSの結果から
発刊年月 2014年 05月
著者 松田 尚久 国立がん研究センター中央病院内視鏡科
著者 佐野 寧 佐野病院消化器センター
著者 尾田 恭 尾田胃腸内科・内科
著者 金子 和弘 国立がん研究センター東病院消化管内視鏡科
著者 工藤 進英 昭和大学横浜市北部病院消化器センター
著者 谷口 浩和 国立がん研究センター中央病院病理科
著者 堀田 欣一 静岡県立静岡がんセンター内視鏡科
著者 藤井 隆広 藤井隆広クリニック
著者 Japan Polyp Study Workgroup
【 要旨 】 5mm以下の大腸微小腫瘍性病変の臨床病理学的特徴像について,Japan Polyp Studyにおける1次TCS発見病変を対象に検討を行った.微小腫瘍性病変は,年齢とともに右側結腸にシフトする傾向が認められ,男女ともその約1/3が横行結腸に認められた.微小腫瘍性病変全体に占める高度異型腺腫・癌の割合はきわめて低いものの,陥凹型病変に限れば,腫瘍径の小さな段階ですでに癌化のポテンシャルを有しており,スクリーニングTCSにおいて同病変群をいかに的確に拾い上げられるかが課題である.
Theme Can we change to treat for diminutive colorectal polyp ?
Title Clinicopathological features of diminutive colorectal polyps : Data from the Japan Polyp Study
Author Takahisa Matsuda Endoscopy Division, National Cancer Center Hospital
Author Yasushi Sano Gastrointestinal Center, Sano Hospital
Author Yasushi Oda Oda GI Endoscopy and Gastroenterology Clinic
Author Kazuhiro Kaneko Division of Digestive Endoscopy and Gastrointestinal Oncology, National Cancer Center Hospital East
Author Shin-ei Kudo Digestive Disease Center, Showa University Northern Yokohama Hospital
Author Hirokazu Taniguchi Pathology and Clinical Laboratory Division, National Cancer Center Hospital
Author Kinichi Hotta Division of Endoscopy, Shizuoka Cancer Center
Author Takahiro Fujii TF Clinic
Author the Japan Polyp Study Workgroup
[ Summary ] Colorectal cancer is the third most prevalent cause of cancer related mortality in Japan. In terms of secondary prevention, early detection and endoscopic removal of adenomatous polyps reduces the incidence and mortality rates for colorectal cancer. Therefore, colonic polyps with malignancy potential are routinely removed using endoscopic procedures. During colonoscopy, small and diminutive colorectal polyps are commonly encountered. It is estimated that at least one adenomatous polyp is detected in approximately half of all patients undergoing screening colonoscopy. We evaluated the clinicopathological features of diminutive colorectal polyps based on data from initial total colonoscopies (1st TCS) of the Japan Polyp Study (JPS). A total of 3,827 diminutive colorectal polyps (≤5 mm) were detected and removed removed endoscopically. There were 3,784 low-grade adenomas (98.9 %), 34 high-grade adenomas (0.9 %), 8 intramucosal cancers (0.2 %) and 1 submucosal invasive cancer (0.03 %). In terms of distribution, 1,354 lesions (35.4 %) were located in the transverse colon (22.1 % : sigmoid colon, 20.5 % : ascending colon, 10.5 % : descending colon, 6.3%:rectum, 5.2 % : cecum). With increased patient age, the distribution of diminutive polyps shifted to the right-side of the colon. Morphologically, the prevalence of "depressed lesions [IIc/IIa + IIc/Is + IIc (NPG type)]" was much lower [27/3,827 (0.7 %)] than that of polypoid and flat lesions. However, the incidence of high-grade adenomas or cancers increased to as much as 11 %. Therefore, we should pay closer attention to identification of diminutive depressed colorectal lesions during screening and surveillance colonoscopy.