[Recent advances in endoscopic mucosal resection for early gastric cancer]

Our indications of endoscopic mucosal resection (EMR) for early gastric cancer (EGC) as a radical treatment are as follows: 1) histology: intestinal type; 2) macroscopic type: IIa and IIc; 3) without ulcerative change. We do not put restrictions on the size of the lesion. EMR is performed on lesions which are suspected to have submucosal invasion for a diagnostic purpose. The ratio of EMR cases to the total EGC cases is increasing in recent years and amounted to about 40% of EGCs treated at the National Cancer Center Hospital in '96. From '87-'96, we had 440 cases of EGCs (intestinal type, histologically) at the National Cancer Center Hospital and National Cancer Center Hospital East. Eighty-five cases (19.3%) turned out to have submucosal invasion and judged non-curative resection. The overall rate of cut-end-free cases was 72.3%, while the overall rate of curative resection (excluding cases with submucosal invasion) was 63.0%. Though we had 37 cases of recurrence after EMR, there were no cases of death from the original disease with additional treatment or observation (due to complication or age). The cut-end-free rates of each period ('87-'90, '91-'93, '94-'96) were 53.1%, 61.3% and 81.6%, respectively. The mean diameter of the lesion of each period became larger, at 11.9 mm, 12.0 mm and 14.0 mm, respectively. To resect a larger lesion in one piece, we began EMR with cutting the mucosa around the lesion using a newly improved endoscopic device called an insulation-tipped diathermic knife (IT knife) from '95. With this IT knife, we could resect 75% of the lesions sized 11-20 mm in one piece, while we could resect 29% with the conventional method (strip biopsy). Though the results of EMR are improving in recent years, new endoscopic technics of EMR to resect easily and surely are expected.