biostudies-literatureMayer CNational Institutes of Health National Cancer InstituteNHLBI NIH HHSUniversity of Michigan-Ann ArborNational Institutes of Health102001https://www.ebi.ac.uk/biostudies/studies/S-EPMC11970396biostudies-literatureUnknown6(3)Lighting interventions can mitigate fatigue by promoting circadian rhythmicity. We test whether individualized, wearable-based lighting interventions delivered via a mobile app reduce cancer-related fatigue in a randomized controlled trial with 138 breast cancer, prostate cancer, and hematopoietic stem cell transplant patients. Participants are randomized to tailored lighting intervention or control. The primary endpoint is PROMIS fatigue 4a at trial end, with secondary endpoints including change in daily fatigue, sleep, anxiety, depression, physical function, and overall health. Fatigue T-scores at week 11 do not differ between groups but decrease significantly from week 1 to week 11 (3.07 points, p = 0.001) in the intervention group, with a significant final-week treatment effect (p = 0.Cell reports. MedicineA circadian and app-based personalized lighting intervention for the reduction of cancer-related fatigue.PMC11970396K24 HL1568962T32AR007422-41SBIR R43CA236557Choi SWTewari MMayer CBowen ZClingan CWalch OReichert ZRDempsey WForger DBRozwadowski MAlumkal JJHenry NLHannay KfalseA circadian and app-based personalized lighting intervention for the reduction of cancer-related fatigue.Lighting interventions can mitigate fatigue by promoting circadian rhythmicity. We test whether individualized, wearable-based lighting interventions delivered via a mobile app reduce cancer-related fatigue in a randomized controlled trial with 138 breast cancer, prostate cancer, and hematopoietic stem cell transplant patients. Participants are randomized to tailored lighting intervention or control. The primary endpoint is PROMIS fatigue 4a at trial end, with secondary endpoints including change in daily fatigue, sleep, anxiety, depression, physical function, and overall health. Fatigue T-scores at week 11 do not differ between groups but decrease significantly from week 1 to week 11 (3.07 points, p = 0.001) in the intervention group, with a significant final-week treatment effect (p = 0.2025-01-01T00:00:00Z2025 Mar2026-06-02T00:02:52.517Z2025-07-11T03:03:53.605ZS-EPMC119703964005690810.1016/j.xcrm.2025.102001