Factors associated with surveillance colonoscopy adherence among survivors and previvors with Lynch syndrome: results from a tertiary cancer center in the US

Authors: Pande M, Thirumurthi S, Lum PJ, Mork ME, Bannon SA, Peterson SK, Vilar Sanchez E, You YN, Rodriguez-Bigas MA, Lynch PM

Category: Survivorship & Health Outcomes/Comparative Effectiveness Research, Electronic Health Records (EHRs)
Conference Year: 2018

Abstract Body:
Purpose: Lynch syndrome, caused by inherited mutations in DNA mismatch repair (MMR) genes, is associated with increased lifetime risk of colorectal cancer. Therefore, standard of care guidelines recommend surveillance by colonoscopy every 1-2 years. Our goal was to identify predictors and outcomes of delayed versus on-time surveillance. Methods: Retrospective surveillance data were abstracted from endoscopy databases from 2001-2017, for all confirmed pathogenic MMR mutation carriers, with and without history of cancer (i.e. survivors and previvors). Patients that received at least 2 successive screening colonoscopies were analyzed (n=195). Delayed surveillance was defined as colonoscopy interval of >2 years between one or more successive colonoscopies. Multivariable logistic regression was used to analyze the association of sex, race, survivor/previvor status, age at first colonoscopy, MMR gene mutated, and adenoma/carcinoma outcomes, with delayed surveillance. Results: The sample was 84% non-Hispanic white, 51.4% male, and 74% cancer survivors. Of the 833 colonoscopies performed, 89.4% were on-time, at ‰¤2 year interval. Mean interval was 12.6 months for on-time surveillance and 36.8 months for delayed. Surveillance started earlier for previvors than for survivors (mean age 43.3 vs. 53.9 years, P<0.01), mean number of colonoscopies was 4.7 vs. 6.5, and previvors had a higher proportion of one or more delayed colonoscopies than survivors (15.3% vs. 9.4%, P=0.03). On multivariable analysis, delayed surveillance was associated with being a previvor (OR: 1.70, 95% CI: 1.00 - 2.91, P= 0.05), and being female (OR: 1.83, 95% CI: 1.15 — 2.89, P=0.005). Delayed surveillance was not associated with race/ethnicity, age at first colonoscopy, MMR gene mutated, or positive findings on colonoscopy (adenoma detection rate 27.3% vs. 25.8% and carcinoma 3.4% vs. 1.5%, P>0.05). Conclusion: Overall rates of delayed surveillance were low (10.6%). Delayed surveillance was more likely among women than men, and among previvors compared to survivors. There was no difference in adenoma/carcinoma detection, although few interval cancers were detected, suggesting longer surveillance intervals may be acceptable for Lynch syndrome, if confirmed by larger prospective studies.

Keywords: Lynch syndrome, surveillance colonoscopy, adherence to guidelines, survivors and previvors