Is it possible to predict the procedural time of endoscopic submucosal dissection for early gastric cancer?

Endoscopic submucosal dissection (ESD) has been expected to be a possible curative treatment, especially for node-negative early gastric cancer (EGC). We investigated the influential factors on the procedural time of gastric ESD with a Flex knife for the estimation. In 222 intestinal-type EGC resected by ESD experts with established techniques, age, sex, location, circumference, gross type, tumor size, tumor depth, ulcerative findings, the period of ESD, the operator, and the experience of the operator were retrospectively analyzed. Predictors with a significant difference, as determined by multivariate analysis, were used to compose a predictive formula of procedural time. Location, gross type, tumor depth, ulcerative findings, and tumor size were considered influential factors on the procedural time by univariate analysis. Location in the upper-third of the stomach, presence of ulcerative findings, and > 20 mm in size were independent factors, as determined by multivariate analysis. Procedural time (min) was nearly equal to the maximal tumor size (mm) multiplied by 2.5, and an additional 40 min was required if the tumor was located in the upper-third of the stomach or had ulcerative findings (in both situations, an additional 80 min was needed). The procedural time of ESD with a Flex knife for EGC can be predicted by tumor size, location, and existence of ulcerative findings. The estimation of procedural time may be very useful to determine the operation schedule.