Higher Vitamin D Levels Associated With Better Outcomes in Colorectal Cancer

Patients with newly diagnosed metastatic colorectal cancer (mCRC) who had higher levels of vitamin D in their blood lived a median eight months longer and experienced greater disease-free survival after their cancer treatment, according to research reported January 12, 2015, at a press briefing in advance of the 2015 Gastrointestinal Cancers Symposium.

If the association is confirmed in randomized phase 3 trials that are currently recruiting participants, vitamin D supplementation could become standard care in this setting, noted lead study author Kimmie Ng, assistant professor of medicine at Dana-Farber Cancer Institute.

Vitamin D is known to inhibit cell proliferation and angiogenesis and has anti-inflammatory effects. Ng’s study looked at the issue in 1043 patients with metastatic disease, who are commonly vitamin D-deficient.

Investigators determined that the median vitamin D level in these patients was 17.2 ng/mL, while the recommended healthy range is 20 ng/mL to 30 ng/mL. Very few study participants reported vitamin D supplementation. Older age, black race, lower dietary and supplemental vitamin D intake, higher body-mass index, worse general physical condition, and lower physical activity were all associated with lower vitamin D levels.

Those who did have higher levels of vitamin D, experienced better health outcomes, which was seen across all subgroups and therapy regimens examined, Ng reported.

“This study will be of great interest to patients with colorectal cancer who frequently want to know if there is anything they can do besides chemotherapy to improve their outcomes,” said symposium presscast moderator Smitha S. Krishnamurthi, associate professor of medicine at Case Western Reserve School of Medicine. “This study adds to the literature that suggests that vitamin D may have protective effects in preventing colorectal polyps and help patients with colorectal cancer live longer.”

Experts agree that patients should have their vitamin D levels checked and have supplementation if needed, although a cause-and-effect relationship has not been established. “It is too early to recommend vitamin D as a treatment for colon cancer, but we do know that maintaining adequate vitamin D levels has other health benefits, such as for bone health,” concluded Ng.