S350 The Effect of Tobacco Smoking on the Burden of Advanced Neoplasia in Patients With Colon Polyps

Introduction: Smoking is a known risk factor for colorectal cancer (CRC). We aimed to evaluate its impact on advanced neoplasia (AdvN) burden in patients with at least 1 colonoscopy-detected polyp. Methods: We retrospectively queried our institution’s endoscopy database, including procedures with at least one non-inflammatory polyp. AdvN was defined as at least 3 tubular/sessile serrated adenomas, size of ≥10 mm (including hyperplastic polyps), and/or villous features on histology. Smoking exposure was defined as low (never smoker, or former smoker with >30 years abstinence or quit < age 40); moderate (active smoker with <20 pack-years [PY], or former smoker with <10 years abstinence and <20 PY); high (current smoker with ≥20 PY, or former smoker with <10 years abstinence and ≥20 PY). Multivariable logistic regression was adjusted by indication, previous colonoscopy, and age and clustered by endoscopists to assess the risk of AdvN presence. Results: We extracted data from 838 colonoscopies. Compared to “low-exposure” females, “low-exposure” male smokers carry 71% increased risk (odds ratio [OR] 1.71, 95% confidence interval [CI] 1.19-2.44, P= 0.003), without difference in risk between moderate-exposure male smokers (P= 0.44); “high-exposure” female smokers carry 27% increased risk (OR 1.27, 95% CI 1.001-1.61, P= 0.048); and “high-exposure” male smokers carry 2-fold risk (OR 2.03, 95% CI 1.02-4.03, P= 0.043), for AdvN. AdvN risk increased by 3.8% per year above age 50 when adjusting for first vs non-first colonoscopy. Conclusion: Tobacco smoking independently increases the AdvN risk in patients with colonoscopy-detected polyps, suggesting increased vigilance for AdvN in “moderate-exposure” male smokers and “high-exposure” female smokers.