早期胃癌臨床診断の実態

Present Status of Clinical Diagnosis for Early Gastric Cancer

　早期胃癌臨床診断の年次推移に関しては，既に胃癌研究会や1971年10月日本臨床外科医学会総会に於て説述せるごとく，1955年X線だけの時は年平均10例，1959年胃カメラ併用により平均35例，1962年ファイバースコープ併用により平均45例，1966年X線テレビの併用で平均50例，そして1968年生検の併用で年平均60例であった．すなわち，早期胃癌発見の年次別頻度の増加は表のごとく診断用器具の開発とその診断技術の進歩によるといえる．しかし早期胃癌の病態やその発見の動機を詳細に検討してみると，必ずしも症例数の増加は臨床診断にのみ依存するとはいえない．よって今回は色々の要素を考慮して，早期胃癌臨床診断の実態とその問題点につき報告する．資料は1952年2月より1970年12月までの，早期胃癌597例およびこれに関連せる症例144例計741例である．この症例中には集検による例は含まれていない．診断法は，1962年早期胃癌全国集計の頃は，500mAレントゲン，胃カメラⅢ型，Ⅳ型（A・B）およびHirschowitzのファイバースコープのみであった．そして1968年以後はX線テレビ，胃カメラVa，GTFS，町田SLファイバースコープ，生検は町田BLを使用している．その他の詳細は表に示す通りである．

　During the past 19 years 1952 to 1970, 597 of early gastric cancer were operated on at Yokoyama Gastrointestinal Hospital. However, pathways through which the diagnoses were established differ among the cases. In 389 cases (65.2％) preoperative diagnosis was confirmed by histological study of removed stomachs (Group A); in 46 (7.7％) initial diagnosis of advanced cancer was reversed to early cancer by postoperative examinations (Group B); and in 162 (27.1％) diagnosis of benign lesions prior to operation was corrected by histology to that of early cancer (Group C). Contrariwise, 61 cases assumed as early cancer later proved to be advanced cancer (Group D), while 83 of “preoperative” early cancer were found benign after the operation (Group E).

　During the same period the annual number of cases of Group A increased markedly in accordance with the development of diagnostic apparatus. In 1961, when diagnosis was done mainly by x-ray and gastrocamera (Type Ⅲ and Ⅳ), only 22 cases were detected, but since gastrofiberscopic biopsy was introduced in 1968 the number of early cases more than doubled. Nevertheless, there were still as many as 208 cases (34.8％) initially mistaken for benign lesions, mostly presumed to be benign gastric ulcers (Group C), while a number of cases in the Group E with acute shallow ulcers, ulcer scars and erosive gastritis were incorrectly diagnosed as early malignancy before the operation. It is emphasized therefore that false positive and false negative cases should be lessened to a minimum degree by active and precise application of gastrofiberscopic biopsy now available.