Higher levels of Vitamin D in the blood are associated with a much better chance of surviving bowel cancer

August 01, 2014

Higher levels of Vitamin D in the blood are associated with a much better chance of surviving bowel cancer

Researchers funded by Cancer Research UK compared the level of Vitamin D in the blood of bowel cancer patients and higher levels were connected to better chances of surviving. A team led by Dr Lina Zgaga from the School of Medicine at Trinity College Dublin cooperating with a team of researchers led by Professor Malcolm Dunlop of the university of Edinburgh analyzed data from close to 1,600 patients treated for colon cancer that had not spread to other parts of the body (metastasized).

They found that having a higher level of Vitamin D in the blood after time of diagnosis for the cancer led to improved rates of survival 10 years after diagnosis with 80% of these still alive at the decade mark. Having a lower level of Vitamin D in the blood led to an increased risk of dying before the five year mark following diagnosis with 20% deceased before the five-year point. To put it another way patients with the highest levels of vitamin D have half the risk of dying compared with those with the lowest levels, according to the research. The greatest benefit of vitamin D was seen in patients with stage-2 disease, at which the tumor may be quite large but the cancer has not yet spread.

Dr Zgaga explains "We found significantly improved prognosis in patients with higher levels of vitamin D. However, the outstanding concern was to disentangle whether vitamin D is directly affecting survival, or if it is just a marker of a healthier lifestyle. For example, more active people tend to spend more time outside and also have higher vitamin D levels, and because the two come together, it is difficult to determine if it is physical activity or vitamin D that drives the higher rate of survival."

"By using genetic markers in our analysis, we were able to get further evidence that suggests vitamin D is causally related to improved survival in bowel cancer patients. This is very important, as it strongly suggests that vitamin D supplementation could be beneficial for bowel cancer patients."

"These initial findings are promising and particularly relevant for Ireland, because the number of people living with cancer is increasing and vitamin D deficiency is very common here." said Dr Zgaga.

Dr Dunlop said it suggested vitamin D supplements may be worth exploring for bowel cancer patients.

"The result from the bowel cancer study has prompted us to explore the role of vitamin D in cancers of the stomach and the esophagus. Prognosis in patients diagnosed with esophageal or gastric cancers is very poor, even when the cancer is caught in an early stage. We must explore any therapeutic options that have the potential to improve prognosis in these patients." Dr Zgaga said.The study is published in the Journal of Clinical Oncology.