Urashima M, et al. - In this randomized clinical trial with 417 patients with digestive tract cancers (mean age, 66 years; male, 66%; esophageal cancer, 10%; gastric cancer, 42%; colorectal cancer, 48%), researchers ascertained if postoperative vitamin D₃ supplementation can improve survival of these patients overall and in subgroups stratified by 25-hydroxyvitamin D (25[OH]D) levels. Patients were randomized to receive oral supplemental capsules of vitamin D (2000 IU/d; n = 251) or placebo (n = 166). Findings revealed that vitamin D supplementation vs placebo, did not lead to a significant improvement in relapse-free survival at 5 years in patients with digestive tract cancer.