AUDIT OF ESD FOR COLORECTAL MUCOSAL LESIONS AT A SINGLE CENTER FROM A REGION NON ENDEMIC FOR COLORECTAL CANCER – CLINICAL OUTCOMES AND LEARNING CURVE

Aims Colorectal ESD is technically challenging and has significant learning curve. Study reports results of in-house audit of ESD’s for colorectal mucosal lesions at single center and analyses learning curve for ESD atcenter in region non endemic for colorectal cancer.

Methods Retrospective analysis of prospectively maintained database of ESD by single operator for colorectal mucosal lesions over 8-years (2011–19). Database divided into 3 phases (40 each) to assess learning curve. S graphically represented using Individuals &moving Range (XmR) trend chart. Proceduralmastery to achieve consistent beneficial outcomes graphically represented using cumulative sum (CUSUM) curve.

Results N = 120; mean age – 58 years (5–88), 70 males (58.3%). Mean S for phases 1, 2, 3 = 4.9, 6.3, 8.2 cm²/hour respectively.Failed ESD – 4 (3.3%) (deep invasion – surgery). Enbloc resection – 116/120 ((96.7%), histological R0 resection – 90/120 (75%). AE’s −17 (14.2%)- muscle injury (7), bleeding (10); treated endoscopically. AE frequency uniform inall phases. Lesion location – proximal 20, distal 42, rectum 58. Lower S (5.2 cm²/hour)for proximal than distal lesions (6.8 cm²/hour) &rectum (6.6 cm²/hour)(OR = 3.36, 95% CI-1.19 to 9.46). Repeat procedure- slower S (4.2 cm²/hour) vs naïve (6.6 cm²/hour) (OR = 3.82, 95% CI-0.39 to 37.86). Histology -premalignant- 89, mucosal cancer – 18, invasive cancer – 7, other – 6. Malignant – slower S (5.2 cm²/hour) vs. benign (6.3 cm²/hour)(OR = 3.92, 95%CI-1.36 to 11.30). CUSUM analysis – approximately 80 resections required for colorectal ESD mastery. Median follow up – 12 months (IQR 3–60). Recurrence – 2 (1.7%) treated by ESD -R0 resection. Late AE – stricture – 3 (2.5%) – dilatation.

Conclusions Audit demonstrates that ESD can be safely implemented in clinical practice in region non endemic for colorectal cancer. Adverse events infrequent and managed endoscopically. Learning curve is approximately 80 procedures. Proximal lesions and mucosal cancers were factors associated with technical difficulty.