Faculty Bibliography

BACKGROUND:Endoscopic polypectomy could be an appropriate, definitive treatment for pathologic T1 (pT1) colon polyps without high-risk features. Prior studies suggested worse prognosis for proximal versus distal advanced-stage colon cancers following curative treatment. However, there is limited evidence on the prognostic impact of tumor location for pT1s. PATIENTS AND METHODS/METHODS:This was a retrospective cohort study using the Surveillance, Epidemiology, and End Results database to identify adults with T1NxMx or T1N0-3M0/x colon adenocarcinoma from 2000 to 2019. RESULTS:A total of 3398 patients underwent endoscopic polypectomy (17% proximal) and 28,334 had a partial colectomy (49% proximal) for pT1 adenocarcinoma. Following endoscopic polypectomy, 5-year overall and cancer-specific survival rates were 64% and 91% for proximal versus 83% and 96% for distal polyps, compared with 82% and 95% for proximal versus 88% and 97% for distal tumors after colectomy. In multivariable models, there was a greater difference in overall survival between proximal and distal polyps for those who underwent endoscopic versus surgical resection [hazard ratio (HR) 1.73, 95% confidence interval (CI) 1.49-2.02 vs. HR 1.13, 95% CI 1.08-1.18]. Patients with proximal versus distal polyps who underwent polypectomy also exhibited increased cancer-specific mortality (HR 1.94, 95% CI 1.37-2.75). However, cancer-specific survival variations based on tumor location were no longer observed in patients undergoing partial colectomy (HR 1.09, 95% CI 0.98-1.21). CONCLUSIONS:Proximal tumor location was independently associated with worse overall and cancer-specific survival following endoscopic polypectomy. However, after colectomy, the cancer-specific disparity based on tumor laterality was mitigated. These findings suggest that proximal location may be considered a high-risk feature in endoscopic polypectomy.

INTRODUCTION/BACKGROUND:Risk factors for serrated polyps (SPs) are not well understood. METHODS:Multivariable analyses of data from a multicenter colonoscopy-based study estimated odds ratios for having either a sessile serrated lesion or traditional serrated adenoma according to participant characteristics. RESULTS:Six thousand seventy-eighty participants were included in the analyses (565 with either a sessile serrated lesion or traditional serrated adenoma). White race was associated with a higher risk of SPs compared with Black race (adjusted odds ratio 4.64, 95% confidence interval 1.89-11.41). Obesity and current smoking were also associated with a higher risk of SPs. DISCUSSION/CONCLUSIONS:White race, smoking, and obesity are risk factors for precancerous SPs.

INTRODUCTION/BACKGROUND:Colorectal cancer (CRC) screening is now recommended at the age of 45 years in the United States. However, information regarding the adenomas detection rate (ADR) and sessile serrated lesions (SSLs) in 45- to 49-year-old individuals is limited. In addition, the impact of lowering the screening age to 45 years on the ADR and the detection rate of SSLs is not well elucidated. This systematic review and meta-analysis aims to report the overall ADR and SSL detection rate in 45- to 49-year-old individuals undergoing colonoscopy. METHODS:We searched MEDLINE, EMBASE, SCOPUS, Web of Science, ClinicalTrials.gov , and the Cochrane database from inception through October 2022 to identify studies reporting on ADR and SSL detection rates in 45- to 49-year-old individuals undergoing colonoscopies for all indications. This approach acknowledges the possibility of including individuals undergoing diagnostic colonoscopies or those with increased risk factors for CRC. We also conducted a separate analysis examining ADR in average-risk individuals undergoing screening colonoscopy. The pooled rates with their corresponding 95% confidence intervals (CIs) were generated using the fixed-effects model. I2 was used to adjudicate heterogeneity. RESULTS:Sixteen studies met the inclusion criteria. All studies were retrospective except one; 3 had data from national/local registries. There were 41,709 adenomas detected across 150,436 colonoscopies. The pooled overall ADR was 23.1% (95% CI 19.7%-27.0%, I2 = 98.6%). The pooled ADR in individuals with average risk of CRC from 7 studies was 28.2% (95% CI 24.6%-32.0%, I2 = 96.5%). The pooled overall SSL detection rate from 6 studies was 6.3% (95% CI 3.8%-10.5%, I2 = 97%). The included studies were heterogeneous because of differences in the inclusion and exclusion criteria and patient population. DISCUSSION/CONCLUSIONS:In 45- to 49-year-old individuals undergoing a colonoscopy for any indication, the ADR and SSL detection rates were 23.1% and 6.3%, respectively. We conclude that these outcomes in 45- to 49-year-olds are comparable with individuals aged 50-54 years.

BACKGROUND:Advanced adenomas (AAs) with high-grade dysplasia (HGD) represent a risk factor for metachronous neoplasia, with guidelines recommending short-interval surveillance. Although the worse prognosis of proximal (vs distal) colon cancers (CCs) is established, there is paucity of evidence on the impact of laterality on the risk of subsequent neoplasia for these AAs. METHODS:Adults with HGD adenomas undergoing polypectomy were identified in the Surveillance, Epidemiology, and End Results database (2000-2019). Cumulative incidence of malignancy was estimated using the Kaplan-Meier method. Fine-Gray models assessed the effect of patient and disease characteristics on CC incidence. RESULTS:Of 3199 patients, 26% had proximal AAs. A total of 65 cases of metachronous adenocarcinoma were identified after polypectomy of 35 proximal and 30 distal adenomas with HGD. The 10-year cumulative incidence of CC was 2.3%; when stratified by location, it was 4.8% for proximal vs 1.4% for distal adenomas. Proximal location was significantly associated with increased incidence of metachronous cancer (adjusted hazard ratio, 3.32; 95% CI, 2.05-5.38). CONCLUSION/CONCLUSIONS:Proximal location of AAs with HGD was associated with >3-fold increased incidence of metachronous CC and shorter time to diagnosis. These data suggest laterality should be considered in the treatment and follow-up of these patients.

BACKGROUND/UNASSIGNED:Colon capsule endoscopy (CCE) has gained momentum as an alternative modality for the investigation of the lower gastrointestinal tract. Of the few challenges that remain, the comparison and - eventually - matching of polyps at different timestamps leads to the potential for double reporting and can contribute to false-positive findings and inaccuracies. With the impending artificial intelligence integration, the risk of double reporting the same polyp due to the lack of information on spatial orientation underscores the necessity for establishing criteria for polyp matching. OBJECTIVES/UNASSIGNED:This RAND/University of California, Los Angeles (modified Delphi) process aims to identify the key factors or components used to match polyps within a CCE video. This involves exploring the attributes of each factor to create comprehensive polyp-matching criteria based on international expert consensus. DESIGN/UNASSIGNED:A systematic qualitative study using surveys. METHODS/UNASSIGNED:A panel of 11 international CCE experts convened to assess a survey comprised of 60 statements. Participants anonymously rated statement appropriateness on a 1-9 scale (1-3: inappropriate, 4-6: uncertain and 7-9: appropriate). Following a virtual group discussion of the Round 1 results, a Round 2 survey was developed and completed before the final analysis. RESULTS/UNASSIGNED:The factors that were agreed to be essential for polyp matching include (1) timestamp, (2) polyp localization, (3) polyp vascular pattern, (4) polyp size, (5) time interval of the polyp appearance between the green and yellow camera, (6) surrounding tissue, (7) polyp morphology and (8) polyp surface and contour. When five or more factors are satisfied, it was agreed that the comparing polyps are likely the same polyp. CONCLUSION/UNASSIGNED:This study has established the first complete criteria for polyp matching in CCE. While it might not provide a definitive solution for matching difficult, small and common polyps, these criteria serve as a framework to guide and facilitate the process of polyp-matching.