Learning curve for endoscopic submucosal dissection of XXXX .

@entity1 @entity82 @entity548 @entity5 @entity418
UNASSIGNED: There is a significant learning curve for endoscopic submucosal dissection of @entity418 that has not been fully characterized. This retrospective study included 33 consecutive superficial @entity418 for analysis of the learning curve for esophageal endoscopic submucosal dissection based on a single, novice endoscopist's experience. The study was divided into three periods (T1, T2, and T3) of 10 endoscopic submucosal dissection procedures in chronological order, with 13 procedures in the last period. @entity1 factors (age, sex, coexistent esophageal varices, or @entity82 ) and @entity5 factors (location at upper esophagus, involving >3/4 esophageal circumference) for endoscopic submucosal dissection were not statistically different between the periods. The mean procedure time was 74.6   min/cm(2) , 23.4   min/cm(2) , and 10.5   min/cm(2) for T1, T2, and T3, respectively. The procedure time decreased over time (P = 0.02) and post hoc test revealed significant difference was only between T3 and T1 (P = 0.019). The en bloc resection rate was 50%, 100%, and 92.3% for T1, T2, and T3, respectively (P for trend = 0.015). R0 resection rate was 40%, 100%, and 84.6% for T1, T2, and T3, respectively (P for trend = 0.023). Two @entity1 had complications: each one @entity1 in T1 and T3 period experienced major @entity548 during the procedure (P for trend = 0.875). None of the @entity1 had esophageal perforation. The results of the study concluded that at least 30 cases of endoscopic submucosal dissection of @entity418 are needed for a novice endoscopist to gain early proficiency in this technique.
