01 May Vitamin D Linked to Better Outcomes in Several Types of Cancer
MedicalResearch.com: What are the main findings of the study?
Dr. Wang: This meta-analysis has systematically reviewed 25 relevant studies composed of 17,332 cancer cases to give a comprehensive perspective on the relationship between vitamin D and cancer patient outcomes. Our result demonstrated that vitamin D levels are linked to better outcomes in several types of cancer patients. The strongest link was found in breast cancer, lymphoma and colorectal cancer. There was less evidence of a connection in people with lung cancer, gastric cancer, prostate cancer, leukemia, melanoma or Merkel cell carcinoma, but the available data were positive. We also found that a 10 nmol/L increase in vitamin D levels was tied to a 4 percent increase in survival among people with cancer.
MedicalResearch.com: Were any of the findings unexpected?
Dr. Wang: Among the 25 included studies, one study that performed with metastatic colorectal cancer patients suggest a null association between circulating 25(OH)D levels and cancer outcomes. This data suggest that vitamin D may have a limited impact for patients with metastatic colorectal cancer. We are also surprising to find that after excluding the study that mentioned above, no significant heterogeneity was found among studies regarding the associations between the circulating 25(OH)D levels and the outcomes of colorectal, breast cancer or lymphoma patients. The studies to date seen to be consistent in the conclusion that higher levels of vitamin D are associated with reduced cancer mortality. Though future intervention study is needed to confirm, vitamin D supplementation is suggested to be performed as early as possible in cancer prevention.
MedicalResearch.com: What should clinicians and patients take away from your report?
Dr. Wang: Close attention should be paid to vitamin D levels in people who have been diagnosed with cancer. Patients with lower level of vitamin D may have worse prognosis, more stringent treatment should be performed for those patients and more attention should be paid to those patients.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Dr. Wang: Vitamin D status appears to be associated with cancer patient outcomes, and its causality with cancer remains to be determined. Randomized, placebo-controlled trials could elucidate the potential benefits of vitamin D on outcomes for cancer patients. More intervention studies are required to elucidate the clinical benefits of vitamin D supplements for cancer patients.
The Impacts of Circulating 25-Hydroxyvitamin D Levels on Cancer Patient Outcomes: A Systematic Review and Meta-Analysis
Hui Wang, MD, PhD , Mian Li, Peizhan Chen, Jingquan Li, Ruiai Chu and Dong Xie