Abstract A148: Increase in colorectal cancer screening among rural and remote Alaska Native peoples using the multi-target stool DNA: A randomized controlled trial

Abstract Background: Alaska Native people are committed to increasing colorectal cancer (CRC) screening to reduce the high rate of CRC in this population. We conducted a community-level cluster randomized controlled trial (RCT) to evaluate the impact of multi-target stool DNA test introduction (mt-sDNA; Cologuard® Exact Sciences, Madison WI) on CRC screening in southwest Alaska Native communities using a mt-sDNA pre-processing lab in Anchorage, Alaska. Methods: A total of 32 rural/remote Alaska Native communities were evenly randomized to either high intensity patient navigation or medium intensity mailed health education compared to 14 communities receiving standard of care (screening recommendations at health care visits). The intervention was conducted from April 2021-February 2023. Outcome measures included CRC screening completion within 12 months and method used (mt-sDNA vs colonoscopy). Results: A total of 2032 Alaska Native participants (mean [SD] age, 56 [8.4] years; 817 women [40%]) were enrolled: 587 participants randomized to usual care, 696 participants randomized to the mailed education arm, and 749 participants randomized to the patient navigation arm. The mt-sDNA test was significantly preferred over colonoscopy by both mailed education participants (68%) and patient navigation participants (71%) (p<0.01). Mt-sDNA was somewhat more preferred by older participants ages 65-75 (79%) vs younger participants ages 45-54 (64%). Both men (71%) and women (68%) significantly preferred mt-sDNA compared with colonoscopy (p<0.01). Overall, 38% of those in the patient navigation intervention completed screening compared with 33% in the mailed education intervention and 10% in the usual care arm. No significant differences were observed in mt-sDNA completion between the patient navigation arm (154 participants [40%]) and the mailed education arm (100 participants [36%]) (p= 0.34). Colonoscopy completion (not including follow-up colonoscopies after abnormal stool tests) was higher in both the patient navigation arm (112 participants [44%]) and the mailed education arm (87 participants [43%]) compared with usual care (38 participants [14%]). Over 61% of kits sent to participants were completed and returned, however, 38% of the kits were not able to be processed, primarily because of mail transit time exceeding the manufacturer’s collection-to-processing limitation of 72 hrs. Conclusions: In this RCT among Alaska Native peoples who were not up to date with CRC screening recommendations, both a mailed education intervention and a patient navigator facilitated intervention were effective at increasing CRC screening compared with usual care. Participants overwhelmingly preferred mt-sDNA for screening but limitations in getting samples to the lab in time for analysis meant that about one-third of mt-sDNA samples were unable to be processed. These findings show that screening outreach and mt-sDNA use can substantially increase CRC screening, but shipping and weather issues remain to be addressed for expanding use of mt-sDNA in rural/remote Alaskan communities. Citation Format: Diana Redwood, Christie Flanagan, Lauren Jeffries, Peter Holck, Danika Bailie, Christine Desnoyers, Joseph Klejka, Lila Rutten, John Kisiel. Increase in colorectal cancer screening among rural and remote Alaska Native peoples using the multi-target stool DNA: A randomized controlled trial [abstract]. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr A148.