1．食道・胃・大腸癌における深達度診断の必要性

Diagnostic Importance of Depth of Tumor Invasion in Esophageal, Gastric, and Colonic Cancer

要旨　癌の治療におけるオーダーメイド化，すなわち個々の症例に見合った過不足のない治療法の選択が求められている今日において，食道・胃・大腸癌の進展状況を反映するパラメーターとして深達度診断は一段と重要性を増している．二重造影を主体としたX線検査および内視鏡による深達度診断はわが国で理論化され，世界をリードしてきた．また，超音波内視鏡の導入に伴い診断精度もいっそうの向上を遂げている．一方，食道癌，胃癌，大腸癌は連続する臓器を母地として発生するにもかかわらず，それぞれ特徴があり生物学的な性格は必ずしも同一ではない．それぞれの診断法の違いを踏まえつつ，術前深達度診断に基づいた治療法選択の意義を考察した．

　The diagnostic importance of the depth of tumor invasion of esophageal, gastric and colonic cancer was discussed. The depth of tumor invasion is one of the indicators of tumor extent, such as lymph node metastasis, distant metastasis and peritoneal (pleural) dissemination. Based on the clinicopathological data of esophageal, gastric and colonic cancer, the risk of positive lymph node metastasis can be estimated from precise observation of the depth of tumor invasion. Local resection such as endoscopic mucosal resection and laparoscopic wedge resection for cases without lymph node metastasis is widely accepted as a means for obtaining a better quality of life (QOL) for early-stage cancer patients.

　The diagnostic procedure for gastrointestinal tract cancers has become greatly improved in recent years. Barium enema radiologic examination and video endoscopy has contributed to the development of the original diagnostic methods in Japan and Western countries.

　Finally, calculation of depth of invasion is having a great impact not only on the planning of therapeutic procedure but also on the patient's QOL resulting from the treatment.