The purpose of this study was to define the indications and limitations of endoscopic resection (ER) of early gastric carcinoma (EGC). Over the 15 year period from 1978 to 1992, 308 early cancers were resected endoscopically either through a single operative intervention or in stages. Of 266 lesions resected in a single step, 222 (85%) entered remission. Forty-four cases had either residual or recurrent lesions. The size, histology and location affected the curability; 89% of Type IIa lesions less than 2 cm were resected curatively, while only 50% of those larger than 2 cm were resected completely. In Type IIc, 83% of lesions less than 1 cm and 57% of those greater than 1 cm were excised completely by ER. In Type IIc, curative ER was possible in 85% of differentiated carcinomas and 43% of undifferentiated carcinomas. The rate of incomplete resection was higher for lesions of the anterior or posterior wall, than for those of the lesser curvature. Semiserial sections of the resected specimens made at 2 mm intervals, indicated that, if the positive margin was confined to one section, cure may be possible by the burning effect. Follow-up showed that there was no single case undergoing endoscopic resection which subsequently died of gastric carcinoma. The lesions that are suitable for ER comprise Type IIa EGC of less than 2 cm in diameter, and Type IIc differentiated adenocarcinoma of less than 1 cm. Lesions in which the entire margin is difficult to observe by front-view endoscopy should be smaller than defined by the above criteria.