早期胃癌臨床診断の実態

Practice of Clinical Diagnosis for Early Gastric Cancer

　1959年末にⅡc型早期胃癌を初めて術前に粘膜癌疑と診断してから，1970年末までの11年間に教室でX線，および内視鏡検査を行なった早期胃癌症例は114例である．このうち術前に早期胃癌と診断できたものは83例，73％であり，進行癌と誤診したもの8例，7％，良性疾患と誤診したもの23例，20％であった．

　1962年に早期胃癌の肉眼分類（内視鏡学会）が設定されるまでの2年間はBorrmann分類にあてはまらない小規模の病変を粘膜癌，あるいは粘膜癌疑としていた．この2年間に15例の早期胃癌例を経験しているが，術前に正診したものは疑診を含めて，9例（60％）に過ぎない．なお，この2年間は私たちが胃カメラ検査を始めた時期であり，地区病院あるいは先輩から胃カメラ検査を依頼される機会が頻繁であったが，この期間に早期胃癌の誤診による良性疾患の切除例はほぼ同数の13例である．

　During the 11 years 1959 to 1970, 114 cases of early gastric cancer encountured. Preoperative diagnosis was correct in 73％; erroneously diagnosed as advanced cancer in 7％ and in 20％ they were mistaken for benign lesions.

　Macroscopical classification of early gastric cancer established in 1962 provided a firm basis for its application to clinical diagnosis of early gastric cancer. Since 1964 the accuracy of preoperative diagnosis rose up and then became stable annually at about 80 per cent. This is because we were used to clinical application of this classification.

　During the two years prior to its establishment almost as many benign lesions were removed by gastrectomy. The decrease of erroneous diagnoses, first becoming apparent in 1962, was most manifest since 1965, when full-scale gastric biopsy was employed. Thereafter cases with benign lesion initially mistaken for early gastric cancer have seldom undergone gastric resection as malignancy. Such a case has been reduced to almost zero now.

　Our next problem lies only in preoperative confirmation of the degree in depth invasion of cancer but also in accurate preoperative diagnosis of Ⅱb subtype cancer.