Use of a Distal Colonoscope Attachment to Increase Detection of Sessile Serrated Adenomas

Introduction: Serrated adenomas are hard to detect polyps that are more likely to be incompletely removed and may account for interval CRC. The Endocuff Vision is a disposable colonoscope attachment that aids in flattening colonic tissue during withdrawal to increase detection of colonic adenomas. Previous studies have shown that Endocuff improves adenoma detection rate (ADR); however, many of these studies have used ADR as a primary endpoint. However, no studies have examined the utility of Endocuff in increasing sessile serrated adenoma detection rate (SSADR) as a primary endpoint. Our study thus aimed to compare differences in SSADR between Endocuff-assisted colonoscopy (EAC) and standard colonoscopy (SC). Methods: This was a single-centered randomized trial between November 2018 and May 2020. Patients presenting for screening colonoscopy were randomized to standard colonoscopy (SC) or to Endocuff-assisted colonoscopy (EAC). Patients with previous colon polyps, colorectal cancer, IBD, polyposis syndromes, or those suspected to have colorectal cancer were excluded. Seven experienced endoscopists performed all colonoscopies in ethnically-diverse outpatient endoscopy centers. Patient demographics, Boston Bowel Prep Score (BBPS), withdrawal time, polyp size, location, and histopathology were evaluated. A sample size of 1,374 subjects was calculated to detect an effect size of 50%, however our study was impacted by the COVID-19 pandemic and only 427 total subjects were enrolled. Results: Four hundred and twenty-seven subjects were enrolled (n=216 in SC and n=211 in EAC). The mean age was 57.3 and 57.9 years in the SC and EAC groups, respectively. There was no difference between groups with respect to gender, withdrawal time, BBPS, lifestyle factors, diabetes, and obesity (Table 1). There was no difference in SSADR (16.2%, 17.1%) in the SC and EAC groups, respectively (P=0.8118). Additionally, there was no statistical difference in ADR (41.2% vs 49.8%) in the SC and EAC groups (P=0.0757). Similar non-significant results were observed for overall mean number of SSA and TA and mean number based on colonic location (proximal vs distal) (Table 1). Conclusion: To our knowledge this is the first randomized evaluation of the utility of Endocuff on SSADR. We found no increased SSADR but we did see a trend towards increased ADR that was almost significant. Future studies are needed to assess the utility of EAC with respect to SSADR, in particular, the use of Endocuff and computer-aided polyp detection compared to standard colonoscopy. Table 1. - Patient Demographics and Adenoma Detection Rates Standard Colonoscopy (N=216) Endocuff-assisted Colonoscopy (N=211) Total (N=427) P-Value Age 0.41221 N (Missing) 216 (0) 211 (0) 427 (0) Mean (SD) 57.3 (7.20) 57.9 (7.71) 57.6 (7.46) Median (IQR) 55.5 (51.0, 62.0) 57.0 (51.1, 63.0) 56.0 (51.0, 63.0) Gender 0.05782 Male 102 (47.2%) 119 (56.4%) 221 (51.8%) Female 114 (52.8%) 92 (43.6%) 206 (48.2%) BMI 0.89261 N (Missing) 215 (1) 210 (1) 425 (2) Mean (SD) 27.7 (4.95) 27.7 (4.60) 27.7 (4.77) Median (IQR) 27.1 (23.8, 31.2) 27.0 (23.9, 30.7) 27.0 (23.8, 30.9) Range 18.9, 40.4 18.0, 42.4 18.0, 42.4 Hgb A1C % 0.54671 N (Missing) 125 (91) 149 (62) 274 (153) Mean (SD) 5.8 (0.97) 5.8 (1.24) 5.8 (1.12) Median (IQR) 5.6 (5.4, 5.8) 5.5 (5.4, 5.8) 5.5 (5.4, 5.8) Range 4.7, 12.8 4.7, 13.1 4.7, 13.1 ETOH Consumption 0.63452 No 63 (29.2%) 66 (31.3%) 129 (30.2%) Yes 153 (70.8%) 145 (68.7%) 298 (69.8%) Heavy ETOH Consumption 0.75792 N (Missing) 65 66 131 No 135 (89.4%) 128 (88.3%) 263 (88.9%) Yes 16 (10.6%) 17 (11.7%) 33 (11.1%) Cigarette Smoking 0.54012 Never 151 (69.9%) 155 (73.5%) 306 (71.7%) Former 55 (25.5%) 50 (23.7%) 105 (24.6%) Current 10 (4.6%) 6 (2.8%) 16 (3.7%) Boston Bowel Preparation Score N (Missing) 216 (0) 210 (1) 426 (1) 0.69371 Mean (SD) 8.7 (0.77) 8.7 (0.86) 8.7 (0.81) Median (IQR) 9.0 (9.0, 9.0) 9.0 (9.0, 9.0) 9.0 (9.0, 9.0) Range 5.0, 9.0 4.0, 9.0 4.0, 9.0 Colonoscope Withdrawal Time (Minutes) 0.71221 Mean (SD) 14.9 (6.67) 14.9 (7.53) 14.9 (7.10) Median (IQR) 14.0 (10.0, 18.5) 14.0 (9.0, 18.0) 14.0 (10.0, 18.0) Range 5.0, 49.0 0.0, 49.0 0.0, 49.0 Sessile Serrated Adenoma Detection Rate (SSADR) 35 (16.2%) 36 (17.1%) 71 (16.6%) 0.81182 Mean Sessile Serrated Adenomas 0.36141 Mean (SD) 0.2 (0.51) 0.3 (0.68) 0.2 (0.60) Range 0.0, 4.0 0.0, 4.0 0.0, 4.0 Sessile Serrated Adenomas Detected in Proximal Colon 0.34851 Mean (SD) 0.2 (0.41) 0.3 (0.66) 0.2 (0.55) Range 0.0, 2.0 0.0, 4.0 0.0, 4.0 Sessile Serrated Adenomas Detected in Distal Colon 0.97731 Mean (SD) 0.04 (0.22) 0.02 (0.15) 0.03 (0.19) Range 0.0, 2.0 0.0, 1.0 0.0, 2.0 Tubular Adenoma Detection Rate (ADR) 89 (41.2%) 105 (49.8%) 194 (45.4%) 0.07572 Mean Tubular Adenomas 0.12311 Mean (SD) 0.7 (1.13) 0.9 (1.40) 0.8 (1.27) Range 0.0, 9.0 0.0, 8.0 0.0, 9.0 Tubular Adenomas Detected In Proximal Colon 0.08311 Mean (SD) 0.5 (0.91) 0.7 (1.12) 0.6 (1.02) Range 0.0, 6.0 0.0, 7.0 0.0, 7.0 Tubular Adenomas Detected in Distal Colon 0.42091 Mean (SD) 0.2 (0.55) 0.3 (0.59) 0.3 (0.57) Range 0.0, 3.0 0.0, 3.0 0.0, 3.0 1Wilcoxon rank sum P-value.2Chi-Square P-value.