内視鏡検診における撮影法の統一と二次読影の重要性

The Importance of Secondary Diagnosis and the Uniformity of Observation Methods in Endoscopic Screening for Gastric Cancer

要旨●対策型内視鏡検診の精度向上を目的として検討を行った．検討①では，当センターの胃部内視鏡観察37枚法（胃部37枚法）について，3年以内の経年発見胃癌326病変の早期癌率は94.5%，粘膜内癌率は79.8%と既報と比べても良好な成績であった．粘膜下層以深に浸潤していた66病変の前回内視鏡画像を検討すると，観察不良8病変：診断不良29病変：診断困難29病変で，約半数は二次読影があれば指摘されうる病変であった．検討②では，胃部37枚法を導入し，当センターが二次読影を行ったS自治体の内視鏡検診について検討した．結果としてプロセス指標は良好で，二次読影の画像評価は後期で有意に改善した．撮影部位と順序を規定した連続性のある撮影法は，内視鏡検診の二次読影を効率化し精度向上に寄与しうると考えられる．

　The current study aimed to improve the sensitivity of endoscopic screening for gastric cancer. Study 1：In 326 gastric cancer detected within 3 years after esophagogastroduodenoscopy, the early cancer rate was 94.5%, and the intramucosal cancer rate was 79.8% using the 37 gastric endoscopy observation method（37-image method）at our center. Previous endoscopic images of 66 lesions invading the submucosal layer and deeper revealed 8/29/29 cases of poor observation/poor diagnosis/difficult to diagnose. A secondary diagnosis could have roughly identified half of the lesions. Study 2：The process index for endoscopic screening in the S municipality, where the 37-image method was introduced and secondary diagnosis was performed by our center, was comparable to other municipalities. In the later stage, the image evaluation of the secondary diagnosis was significantly improved. A method of continuous and comprehensive observation may help improve the efficiency and accuracy of secondary diagnosis in endoscopic screening for gastric cancer.