ADENOMA DETECTION RATE SIGNIFICANTLY VARIES BETWEEN GASTROENTEROLOGISTS AND SURGEONS IN THE NATIONAL VA HEALTHCARE SYSTEM

Introduction: Recent data suggested that cold snare EMR (C-EMR) offers equal efficacy, yet superior safety, compared with traditional hot EMR (H-EMR). We performed a systematic review and meta-analysis to assess the safety of C-EMR compared with H-EMR.


Methods: We performed a comprehensive literature search of MEDLINE (Ovid), Web of Science, Embase, Cochrane Library and CENTRAL, and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) from inception to September 19, 2022. We included studies of endoscopic mucosal resection of colorectal polyps and/or polypectomy of polyps ≥10 mm and reported rates of adverse events including bleeding, perforation, and post polypectomy syndrome. The primary outcome was the adverse event rate for C-EMR vs. H-EMR for colorectal polyps ≥10mm. For comparative data, we reported odds ratios with 95% confidence intervals (CI’s). For cohort studies, we reported proportions with CI’s. We assessed publication bias by funnel plots with the classic fail-safe test. We used forest plots to report pooled effect estimates and assessed heterogeneity using I² and p-values.


Results: Our systematic review identified 1,215 unique citations, 19 of which met our inclusion criteria. In 4 comparative studies (2 randomized control trials and 2 retrospective studies), 413 patients underwent C-EMR, only two of whom suffered delayed bleeding. 35 of the 658 patients undergoing H-EMR suffered delayed bleeding. On random effect modelling, C-EMR carried a significantly lower risk of delayed bleeding compared to H-EMR (OR 0.2 [CI: 0.05 - 0.88], p=0.033, I² = 0%, Fig. 1). In the 10 cohort studies, the pooled rate of delayed bleeding was only 2% (CI: 1.3 – 3.2%), p<0.001, Fig. 2.

The rate of early bleeding was similar between both groups (OR 1.67, [CI: 0.77 - 3.6], p=0.1916, I² = 26%). On random effect modeling, the pooled rate of early bleeding for C-EMR was 1.9% (CI: 1.1% - 3.2%), p<0.001, I² = 12%.

Only one study by Rex et al. reported residual polyps. Margins were positive in 1 of 82 polyps resected by C-EMR and 4 of 65 resected by H-EMR. In the two comparative studies assessing polyp recurrence, there was a trend towards higher recurrence rates in the C-EMR cohort, but it did not reach statistical significance (OR 0.55 [CI: 0.29 - 1.03], p=0.0631, I² = 0).

There were no cases of perforation from C-EMR vs. 16 perforations from H-EMR. This difference did not reach statistical significance. (OR 0.02 [CI: 0.0 – 2.03], p=0.0995).

Conclusions: C-EMR is associated with equal efficacy compared with H-EMR, with similarly low rates of residual polyp tissue and polyp recurrence. The safety of C-EMR, however, is superior, with significantly lower rates of delayed bleeding than H-EMR. Rates of early bleeding are similar between the two methods.

Background:
Single center studies suggest that adenoma detection rates (ADR) vary between gastroenterologists and surgeons. The generalizability of these findings is unclear. We sought to compare ADR between gastroenterologists and surgeons in the US Veterans Health Administration national healthcare system and to examine the association of patient demographic factors with ADR.

Methods:
We identified colonoscopy procedures of all indications using CPT codes from VA national electronic health records between October 2018-September 2022. We used a previously validated text recognition algorithm to determine histology from the associated pathology reports of patients aged 45-75. We classified providers from administrative codes for surgery and gastroenterology. After excluding providers with fewer than 50 colonoscopy procedures, we calculated each provider ADR as the percentage of colonoscopies with at least one adenoma or adenocarcinoma. We compared average ADR in surgeons and gastroenterologists using a 2-tailed t-test and compared the proportion of providers with ADR <30% using a chi-square test. We also calculated provider ADR in patients with different demographics (gender, race, ethnicity, geographic location and FIT+ testing within one year of colonoscopy) and used a generalized linear model to compare the ADRs before and after adjustment for patient demographics.

Results:
We identified 669,434 colonoscopies by 1,095 unique providers. Gastroenterologists (n=906; 82.7%) conducted 88.8% (n=594,710). The patient demographics are shown in the Table. ADR of surgeons (41.4%; 95% CI [39.5, 43.4]) was significantly lower than that of gastroenterologists (53.33%; 95% CI [52.7, 54.0]), p<0.0001 both before and after adjusting for differences in patient demographics. ADRs <30% were observed in 38 of 189 (20.1%) surgeons compared to 19 of 906 (2.1%) of gastroenterologists; p<0.0001. Surgeon ADRs were distributed across proportionally lower values than gastroenterology ADRs (Figure). Within both provider groups, higher ADRs were observed in men vs. women, in whites vs. non-whites, and in patients with a prior vs. no prior FIT test positive, though surgeon ADR remained consistently lower than gastroenterologist ADR. Among the colonoscopies performed after a positive FIT test, the ADR was significantly lower for surgeons (57.3%; 95% CI [53.7, 60.9]) than gastroenterologists (65.9%; 95% CI [64.8, 67.0]), p<0.0001.

Conclusion:
In this large US national healthcare system colonoscopy cohort, surgeons had a significantly lower ADR for colonoscopy of all indications and a higher proportion of endoscopists with ADRs < 30% than gastroenterologists, irrespective of patient demographics. Our findings highlight potential opportunities for targeted quality improvement and further evaluation of colonoscopy training parameters for surgical specialties.