超音波内視鏡による大腸癌の深達度診断―注腸X線検査，大腸内視鏡検査による深達度診断能との比較を含めて

Evaluation of the Depth of Colorectal Cancers Using Endoscopic Ultrasonography in Comparison with Barium Enema and Colonoscopic Examinations

要旨　過去5年間に当科で経験した大腸癌207例を対象に注腸X線検査，大腸内視鏡検査，超音波内視鏡検査による術前深達度診断能の比較検討を行った．症例全体における深達度正診率は注腸X線検査で74.4％，大腸内視鏡検査で76.3％，超音波内視鏡検査で74.9％であり，各検査法の間には差がみられなかった．a/ss～s癌の診断についてはむしろ注腸X線検査や大腸内視鏡検査で有意に高い正診率が得られた．しかし，超音波内視鏡検査の正診率はsm癌，pm癌において他法より高率であり，sm癌においては大腸内視鏡検査，pm癌においては注腸X線検査に比べて有意差が認められた．また，超音波内視鏡検査ではより詳細な深達度診断も可能であり，比較的小さい病変を対象とする場合に超音波内視鏡検査が最も優れた手法であると評価された．

　Diagnostic accuracy of endoscopic ultrasonography for the evaluation of the depth of colorectal cancers was assessed in comparison with those of barium enema and colonoscopic examinations. Two hundred and seven colorectal cancers experienced in our department during the last five years were analyzed. Accuracy rates of the depth of cancer invasion were 74.4% by barium enema, 76.3% by colonoscopic examination and 74.9% by endoscopic ultrasonography. In the patients with a/ss～s cancer invasion, the accuracy rates by barium enema or colonoscopic examinations were significantly higher than that by endoscopic ultrasonography. In the patients with sm or pm cancer invasion, however, the accuracy rate by endoscopic ultrasonography was higher than those by the other methods. Evaluation using endoscopic ultrasonography is considered to be the most useful technique for the diagnosis of relatively small or early cancers.