Vitamin D deficiency in the oncology setting.

Background: Vitamin D deficiency is common in the United States. Regardless of whether or not vitamin D deficiency increases the risk of cancer and decreases survival of cancer, the established adverse impact of its deficiency on bone health is of particular concern for cancer patients. The extent of vitamin D deficiency is not well defined in the oncology setting, and there are no standardized protocols for screening and supplementation for individuals found to be deficient in vitamin D.