Determining early gastric cancer lesions appropriate for endoscopic submucosal dissection trainees: a proposal related to curability.

Endoscopic submucosal dissection (ESD) was introduced worldwide as a new treatment option for early gastric cancer. Our objective was to discuss the limited ESD reports available and to determine the lesions suitable for use in training endoscopists on which lesions are appropriate for ESD. We reviewed a series of ESD reports that have been written on various risk factors related to the resectability or curability of a variety of lesions. These published studies show that certain risk factors such as tumor size and location and the presence of ulceration are closely related to both resectability and curability. Because the combination of these risk factors resulted in a much higher risk than did any single factor, we recently established a 'risk assessment chart' to determine an individual's total risk of treatment failure for early gastric cancer that has been treated using ESD. This risk chart provides a clear indication that small, non-ulcerated lesions located in the lower third of the stomach have a high rate of curative resection and are technically less challenging if ESD is used. We suggest that trainees should gain ESD experience with such lesions before they start to perform ESD on more difficult lesion types that have a lower probability of curative resection. In addition, we suggest that this risk assessment chart is suitable for the pretreatment assessment of curability and the likelihood of successful en bloc resection.