A146 EVALUATION OF A COLONOSCOPY REFERRAL FORM IN QUEBEC: WHICH INDICATIONS CARRIES A HIGHER RISK OF ADVANCED NEOPLASIA?

Abstract

Abstract Background Patients referral for colonoscopy in the province of Quebec are organized through a standardized triage sheet that includes all indications categorized in 5 hierarchal scheduling priorities. In the context of a restricted access to colonoscopy, exacerbated by the COVID-19 pandemic, postponed elective endoscopies lead to potential diagnostic and therapeutic delays in patients with colorectal neoplasia. There is currently an important need to evaluate available tools to improve patients prioritization. Aims This study aims to determine CRC and advanced adenomas (AA) rates associated with indications of priority 3 (P3 fig.1). The secondary objective is to regroup and compare indications with higher and lower rate of CRC and AA. Methods This retrospective study included all adult patients who underwent a single diagnostic colonoscopy from March 2013 to March 2016 following a single FIT test in a tertiary teaching hospital. A literature review informed the adopted definition of higher-risk of CRC and AA according to P3 colonoscopy indications. These include: Positive FIT test (IN5), hematochezia in ≥ 40 years old patients (IN4), unexplained iron deficiency anemia (IN6) and symptoms suspicious of occult colorectal cancer (IN18). Lower risk P3 indications were defined as: suspicion of IBD (IN3), recent change in bowel habits (IN7), polyp viewed on imaging (IN17), inadequate bowel preparation (IN19), and diverticulitis follow-up (IN20). Higher and lower risk indications findings were analyzed. Results In our cohort of 2226 patients, indications for colonoscopy referral according to the standardized form were available for 1806 patients (10 P1, 69 P2, 1056 P3, 56 P4 and 615 P5). In our studied group of P3 indications, the mean age was 62.6±11.3 years, 54.1% were female and 173 (16.4%) patients had a significant finding of CRC or AA (table 1). Patients referred for higher risk indications had a significantly increased rate of CRC and AA (19.3% vs 5.1% p≤ 0.01) compared to patients referred for lower risk indications. Conclusions A standardized colonoscopy referral tool may be adapted to improve prioritization of patients at risk of advanced neoplasia. These findings are especially relevant in the context of limited access to colonoscopy like during a pandemic. Table 1. Detection rate of neoplastic findings for P3 indications(%) Higher-risk indications Lower-risk indications IN4 (N=230) IN5 (N=453) IN6 (N=156) IN18 (N=3) IN3 (N=41) IN7 (N=135) IN17 (N=5) IN20 (N=33) Non-advanced adenomas (NAA) 47(20.4) 192(42.6) 41(26.5) 1(33) 5(12.2) 25(18.5) 4(80) 6(18.2) Advanced adenomas (AA) 21(9.2) 116(25.7) 8(5.2) 0 1(2.4) 8(5.9) 0 1(3) Serrated polyps 11(4.8) 42(9.4) 5(3.2) 0 0 6(4.5) 0 1(3) Carcinoma (CRC) 5(2.2) 7(1.6) 6(3.9) 0 0 1(0.7) 0 0 AA and CRC 26(11.3) 123(27.2) 14(9.0) 0 1(2.4) 9(6.6) 0 1(3) Figure 1: Provincial colonoscopy referral form in Quebec (AH-702) Funding Agencies None