Impact of universal screening of colorectal cancer (CRC) for detection of Lynch syndrome (LS) at a Hispanic-predominant county hospital.

Abstract

199 Background: Historically, the Amsterdam and Bethesda criteria were used to select patients (pts) for LS screening. In 2014, universal screening (US) for LS was shown to be cost effective. Thus, to increase LS screening, we implemented an algorithm for pathologists to reflex immunohistochemistry (IHC) on newly diagnosed CRC. Here, we evaluate the effectiveness of US program with reflex testing for LS for all new CRC. Methods: Retrospective analysis of new diagnoses of CRC (01/2012 – 04/2016): a county hospital with follow-up at NCI-designated CTRC. 3 patient cohorts: 1) PRE-intervention (01/2012–09/2014): screening ordered per old guidelines; 2) PERI (10/2014–02/2015): clinician education on new guidelines; 3) POST (03/2015–04/2016): after implementation. Endpoints: proportion of pts screened and time to screening, quality of family history (FHX) by clinicians, FHX of LS-related cancer, genetic counseling. Results: 381 patients: mean age (57): 69 pts age < 50; 312 pts age ≥ 50. Female 151/male 230; 238 Hispanic/143 Non-Hispanic. % screened: PRE 31% (n = 83), PERI 64% (n = 16), and POST 58% (n = 49) (table for P values). Age < 50 vs. ≥ 50: PRE 56% vs. 25% (P 0.000013), PERI 80% vs. 60% (P 0.38), POST 81% vs. 53% (P 0.02); Loss of any IHC: PRE 12% (n = 10), PERI 19% (n = 3), POST 4% (n = 2); Pts with +screening who received genetic counseling: PRE 30% (n = 3), PERI 67% (n = 2), POST 100% (n = 2). Time from diagnosis to IHC result of < 8 days: PRE 28%, PERI 6%, POST 39%. Adequate FHX in PRE vs POST: 9% vs 20% (P = 0.016). No FHX in PRE vs POST: 47% vs 33% (P 0.019). Conclusions: Significant improvement in number of screens and more timely screening of newly diagnosed CRC pts screened for LS, especially over age 50, were observed after implementation of US. Providers took higher quality FHX after US implementation. Detection for FHX of LS-related cancers significantly improved with US for pts over age 50. Future prospective studies are warranted to evaluate referrals to genetic counselors and diagnoses of LS as well barriers to US. [Table: see text]