[Indications and problems of endoscopic treatment for gastrointestinal tract cancers, with special reference to early gastric cancer].

We carried out a clinicopathologic and endoscopic investigation of the relationship between the presence/absence of lymph node or distant metastasis and several crucial factors using resected specimens of early gastric cancer, and concluded that endoscopic treatment was indicated for four types of early gastric cancer: 1) type IIa less than 2 cm in size, 2) focal cancer, 3) so called "gastritis-like" early cancer less than 2 cm in size and 4) polypoid type with mucosal involvement. Up to now, cases of early gastric cancer have been treated by polypectomy, strip biopsy and laser endoscopy. Residual cancer cells were found in 10 out of 20 resected cases. In 2 out of 54 cases followed up for more than one year without any surgical treatment, cancer cells were discovered by biopsy. The effectiveness rate was estimated to be 84% (62/74). Endoscopic treatment was able to provide high efficiency for early gastric cancer of the above types. Causes of ineffectiveness were a lesion more than 2 cm in size, vertical invasion of the lesion into the submucosa and the location of a lesion in a difficult area such as the prepylorus or the cardia.