Clin Gastroenterol Hepatol. 2023 Jan 5:S1542-3565(23)00004-6. doi: 10.1016/j.cgh.2022.12.026. Online ahead of print.
ABSTRACT
BACKGROUND AND AIMS: Multitarget stool DNA (mt-sDNA) testing is a stool-based screening test for colorectal cancer (CRC). In a single instance of testing, the pivotal FDA-approval study (NCT01397747) found that 16% of mt-sDNA tests were positive, and the positive predictive value (PPV) for CRC or advanced precursor lesions (APL) was 27.3%. We aimed to examine real-world longitudinal performance by determining the test positive rate and PPV of mt-sDNA on the 2nd round of testing.
METHODS: Colonoscopy and pathology reports were retrospectively reviewed for patients with a negative mt-sDNA on the 1st round of screening and a positive mt-sDNA on the 2nd round. Test-positivity rate and PPV for CRC, APL, and any colorectal neoplasia (CRN) were calculated for the 2nd mt-sDNA and compared to baseline PPVs from a previously published cohort of patients from our institution who tested positive on the 1st round of screening.
RESULTS: 2,758 patients completed a 2nd test at a median of 3.2 years after the 1st test. Of these, 422 (15%) had a positive 2nd mt-sDNA. The PPV was 0.25% for CRC, 24% for APL, and 67% for any CRN. There was no significant difference in PPV on the 2nd mt-sDNA test compared to the 1st round (24% vs 28% for APL, P=0.12).
CONCLUSIONS: Mt-sDNA test positive rate and PPV were similar between 1st and 2nd rounds of screening. These observations confirm the utility of a second round of mt-sDNA screening and may inform estimates of mt-sDNA effectiveness for CRC screening.
PMID:36621751 | DOI:10.1016/j.cgh.2022.12.026
