About the Study : Does the addition of high-dose vitamin D to standard treatment improve progression-free survival in patients with metastatic colorectal cancer? In this multicenter, double-blind phase 3 randomized clinical trial in patients with previously untreated metastatic colorectal cancer, the addition of high-dose vitamin D to standard treatment did not significantly improve progression-free survival compared with standard-dose vitamin D (median progression-free survival, 11.8 months vs 10.3 months, respectively). High-dose vitamin D did not improve progression-free survival in patients with metastatic colorectal cancer.
Corresponding Author : Kimmie Ng, MD, MPH, Dana-Farber Cancer Institute, 450 Brookline Ave, Boston, MA 02215 ( Kimmie_Ng@dfci.harvard.edu ).
10.1001/jama.2026.9350
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