3）超音波内視鏡からみた深達度診断

Endoscopic Ultrasonographic Diagnosis of the Depth of Invasion of Gastric Cancer

要旨　治療方針決定のための深達度診断におけるEUSの役割を内視鏡診断と比較検討した．その結果，EUSはUl(＋)病巣において，Ulの深さの診断に有用であったが，肉眼型別，部位別検討では内視鏡と大差なかった．一方，内視鏡診断不一致でEUS正診の症例が20病巣（5.9％）存在し，真のEUS有用例と考えられた．これらの病巣を検討した結果，EUSは内視鏡でSM2～MPと診断された病巣において，早期胃癌では陥凹型で内視鏡による深読みを，進行胃癌ではⅡC様進行胃癌で内視鏡による浅読みを補正するのに有用であった．

　The diagnostic ability of EUS for discerning the depth of invasion of gastric cancer was compared with that of endoscopy in 322 patients with 338 lesions of gastric cancer. The results were as follows;

　1) EUS was useful for the diagnosis of the depth of ulcer or ulcer scar, but, as regards macroscopic type or site of the lesions, the diagnostic ability of EUS was hardly different from that of endoscopy.

　2) We encountered twenty lesions (5.9%) of gastric cancer which were correctly diagnosed by EUS, though inaccurately diagnosed by endoscopy. EUS was definitely useful for diagnosing the depth of invasion of gastric cancer in these lesions.

　3) In early cancer, EUS was useful for depressed lesions which were endoscopically diagnosed SM2～MP to correct the depth of invasion to M1～SM1.

　4) In advanced cancer,EUS was useful for Ⅱc-like advanced cancer lesions, which were endoscopically diagnosed SM2～MP to correct the depth of invasion to SS～.