Endoscopic treatment for subtypes of early gastric cancer

Between April 1986 and September 1998, we diagnosed and treated by endoscopic mucosal resection (EMR) 287 early gastric cancers in 279 patients. The patients were divided into various subgroups, and the outcome of EMR was studied. In addition, the therapy used to treat residual tumor and the outcome of such therapy were also investigated. Among 246 lesions absolutely indicated for EMR, 177 (72.0%) were margin-negative and 69 were margin-positive. Of 41 lesions relatively indicated for EMR, only 21 (51.2%) were margin-negative and 20 were margin-positive. When lesions were classified according to size, 72.7% of those 5 mm or less in diameter and 73.3% of those 6 to 10 mm in diameter were margin-negative. However, the negative margin rate dropped to less than 50% for lesions measuring 11 mm or more. When the lesions were classified according to macroscopic type, the margin-negative rate was 52.9% for elevated type, 65.7% for depressed type, and 52.9% for mixed type (a combination of elevated type and depressed type). When the lesions were classified according to site, margin-negative rates of 70% or more were obtained for lesions located in the lesser curvature of the upper corpus, the posterior wall of the middle corpus, the anterior wall and greater curvature of the lower corpus, the posterior wall and greater curvature of the angle, and the anterior wall and greater curvature of the antrum. The effectiveness rate of the first additional attempt at endoscopic therapy for margin-positive lesions was 92.0% for laser irradiation, 90.9% for heater probe therapy, and 75.0% for additional EMR. One lesion treated with an argon plasma coagulation was not cured.