LEARNING CURVE FOR COLORECTAL ESD

Aims:

To analyze the learning curve of endoscopic submucosal dissections (ESD) for colorectal tumors.

Methods:

The results of the first 170 ESD for colorectal tumors from 09.2007 till 09.2018 have been analyzed. ESD speed, number of complications, rate of en-block resections and snare assistances have been evaluated. All patients were divided into two groups (85 patients each). Age – 61.8 ± 0.73 years, (F – 94, M – 76).

Results:

Rectum – 76 lesions, 55 – in the left colon and 39 – in the right colon. 108 were benign, 62 – malignant (13 of them with submucosal invasion). Tumors were polypoid in 35, non-polypoid in 135 cases (LST-G – 100, NG – 35). The mean tumor size was 14.9 ± 1.7 cm². En-block resection was achieved in 149 cases (87.6%). Average ESD speed was 12.7 mm²/min (average time for 1 cm² was 12.9 min). There were 30 cases with snare assistance (17.6%), 20 perforations (11.7%) and 3 cases of delayed bleeding (1,7%). In the first 85 ESD group there were more rectal and less right-sided tumors than in the second 85 ESD group (45 vs. 31, p = 0.03, and 14 vs. 25, p = 0.04). Tumor size did not significantly differ (12.3 cm² vs. 17.5 cm², p = 0.14). En-block resections and perforation rates were similar in both groups (71 vs. 78, p = 0.16 and 6 vs. 14, p = 0.09). There were less cases of snare assistance in the second group (20 vs. 10, p = 0.04). ESD was faster in the second group: mean time of ESD for 1 cm² was 14.7 min vs. 11.4 min (p = 0.04); mean ESD speed was 11 mm²/min vs. 14.6 mm²/min (p = 0.01).

Conclusions:

ESD speed significantly improved after 85 operations. Snare assisted ESD were less often in the second group. Absence of significant difference in perforation rate can be explained by significant increase of right-sided tumors in the second group.