Risk of Metachronous High-Risk Adenomas and Large Serrated Polyps in Individuals With Serrated Polyps on Index Colonoscopy: Data From the New Hampshire Colonoscopy Registry.
BACKGROUND & AIMS
Surveillance guidelines for serrated polyps (SPs) are based on limited data on longitudinal outcomes of patients. We used the New Hampshire Colonoscopy Registry to evaluate risk of clinically important metachronous lesions associated with SPs detected during index colonoscopies.


METHODS
We collected data from a population-based colonoscopy registry that has been collecting and analyzing data on colonoscopies across the state of New Hampshire since 2004, including rates of adenoma and SP detection. Patients completed a questionnaire to determine demographic characteristics, health history, and risk factors for colorectal cancer, and were followed from index colonoscopy through all subsequent surveillance colonoscopies. Our analyses included 5433 participants (median age, 61 years; 49.7% male) with 2 colonoscopies (median time to surveillance, 4.9 years). We used multivariable logistic regression models to assess effects of index SPs (n = 1016), high-risk adenomas (HRA, n = 817), low-risk adenomas (n = 1418), and no adenomas (n = 3198) on subsequent HRA or large SPs (>1 cm) on surveillance colonoscopy (metachronous lesions). Synchronous SPs, within each index risk group, were assessed for size and by histology. SPs comprise hyperplastic polyps, sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas. In this study, SSA/Ps and traditional serrated adenomas are referred to collectively as STSAs.


RESULTS
HRA and synchronous large SP (odds ratio [OR], 5.61; 95% confidence interval [CI], 1.72-18.28), HRA with synchronous STSA (OR, 16.04; 95% CI, 6.95-37.00), and HRA alone (OR, 3.86; 95% CI, 2.77-5.39) at index colonoscopy significantly increased the risk of metachronous HRA compared to the reference group (no index adenomas or SPs). Large index SPs alone (OR, 14.34; 95% CI, 5.03-40.86) or index STSA alone (OR, 9.70; 95% CI, 3.63-25.92) significantly increased the risk of a large metachronous SP.


CONCLUSIONS
In an analysis of data from a population-based colonoscopy registry, we found index large SP or index STSA with no index HRA increased risk of metachronous large SPs but not metachronous HRA. HRA and synchronous SPs at index colonoscopy significantly increased risk of metachronous HRA. Individuals with HRA and synchronous large SP or any STSA could therefore benefit from close surveillance.
['Anderson|Joseph C|JC|', 'Butterly|Lynn F|LF|', 'Robinson|Christina M|CM|', 'Weiss|Julia E|JE|', 'Amos|Christopher|C|', 'Srivastava|Amitabh|A|']
D000236:Adenoma D000368:Aged D015331:Cohort Studies D003110:Colonic Neoplasms D003111:Colonic Polyps D003113:Colonoscopy D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D016609:Neoplasms, Second Primary D009513:New Hampshire D012042:Registries D018570:Risk Assessment
Risk Factors Colon Cancer Early Detection NHCR