Some cases of early gastric cancer are accompanied with complications of the upper gastro-intestinal tract. The characteristics of these complications were investigated, and the problems of diagnosis and treatment were discussed. Out of 297 cases of early gastric cancer, 18 cases were accompanied with complications of the upper gastro-intestinal tract, including 11 cases of bleeding, a case of perforation and 6 cases of pyloric stenosis. All 18 cases were of the macroscopically depressed type, and about 85 percent of the 297 early gastric cancer cases were of the depressed type. The depressed lesions were often accompanied by ulceration which was an important factor causing the complications, and the mechanism of which appeared to be the same as that of a benign ulcer. There are some cases of early gastric cancer which are discovered by their complications, and it would be more difficult to find an early gastric cancer lesion if there were a benign lesion at the same time. Therefore, it is necessary to take much care when diagnosing and treating cases which have such complications. An endoscopic examination before the operation is especially important, and a biopsy is indispensable.</p
