January 27, 2012. An article published online on January 25, 2012 in Cancer Epidemiology, Biomarkers and Prevention reports an association between higher prediagnostic levels of vitamin D and increased survival among patients with colorectal cancer.
The study evaluated the association between serum vitamin D levels and mortality among 1,202 men and women enrolled in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, which recruited over 520,000 participants from 1992 to 1998. Subjects in the current study were diagnosed with colorectal cancer between enrollment and June, 2003. Blood samples obtained upon recruitment were analyzed for serum 25-hydroxyvitamin D [25(OH)D]. Over a mean follow-up period of 73 months, 444 deaths due to colorectal cancer and 97 deaths from other causes occurred.
Men and women whose serum vitamin D levels were among the top 20 percent of participants had a 31 percent lower risk of dying from colorectal cancer and a 33 percent lower risk of mortality from any cause compared to those whose levels were among the lowest 20 percent. Having a high vitamin D level was protective against cancers of both the colon and the rectum. When subjects were analyzed according to calcium intake, a significant protective effect of vitamin D was observed only among those with high dietary calcium.
“If verified in other studies, calcium supplementation in combination with vitamin D may be potentially useful for improved survival in colorectal cancer patients,” the authors write. “This large and comprehensive study, based on the EPIC cohort has shown that higher blood vitamin D levels before colorectal cancer diagnosis are associated with reduction in colorectal cancer-specific and overall mortality. Further prognostic studies among cancer patients are needed to determine whether 25(OH)D levels at diagnosis and post-diagnosis correlate with those measured prior to diagnosis, and influence all-cause and disease-specific survival among colorectal cancer patients.”