Results of a small clinical trial suggest that supplementing chemotherapy with high doses of vitamin D may benefit patients with metastatic colorectal cancer by delaying progression of the disease, say scientists from Dana-Farber Cancer Institute.
The SUNSHINE trial randomized 139 patients with previously untreated metastatic colorectal cancer. One group took pills containing 4,000 international units (IU) of vitamin D per day along with standard chemotherapy, while the other group took 400 units (about the dose found in a multivitamin) along with chemotherapy.
Vitamin D, which is necessary for bone health, is made in the body through a chemical reaction dependent on sun exposure and is contained in some foods. In laboratory studies, vitamin D has demonstrated anti-cancer properties such as triggering programmed cell death, inhibiting cancer cell growth and reducing metastatic potential. Prospective observational studies have linked higher blood levels of vitamin D with a lower risk of colorectal cancer and improved survival of patients with the disease, but those studies could not prove that vitamin D was the cause.
First randomized clinical trial of vitamin D in patients with metastatic colorectal cancer found delayed disease progression with high dose supplements combined with chemotherapy. These encouraging results are prompting a planned evaluation in a large phase 3 trial.
Credit: Dana-Farber Cancer Institute