Eighty-five patients with gastric carcinoma developing at or involving the cardia were operated on under a newly established principle to prevent a cancer-positive proximal margin. The choice of operative procedure, standard total gastrectomy or extended total gastrectomy, was determined by the degree of proximal extension of carcinoma as confirmed by preoperative examinations. The cancer-positive rate was decreased in this manner to 1.2% from the 13.8% of the controls operated on before the principle was established. Extended total gastrectomy without sternotomy should be used more frequently than that with sternotomy because of the technical advantages. Survival rates of the 85 patients were 48.3% at three years and 30.4% at five years after the operation, and were not significantly different from the controls. As post-operative survival rate is influenced by factors other than transmural extension of the tumor, this study should prompt us to focus on the problem of the proximal surgical margin in surgery for carcinoma of the gastric cardia.