by Erin White
A vitamin D deficiency may increase the chance of developing aggressive forms of prostate cancer for some men who are at high risk for the disease. Prostate cancer is a leading cause of cancer cases among black men and the second-leading cause of cancer deaths among African American men, according to the American Cancer Society.
“Vitamin D deficiency could be a biomarker of advanced prostate tumor progression in large segments of the general population,” says Adam B. Murphy, assistant professor in urology at Northwestern University Feinberg School of Medicine and lead author of a new study published in Clinical Cancer Research.
“More research is needed, but it would be wise for men to be screened for vitamin D deficiency and treated.”
“This is the first study to look at vitamin D deficiency and biopsy outcomes in men at high risk of prostate cancer,” says senior author Rick Kittles, associate professor of medicine at University of Illinois at Chicago. “Previous studies focused on vitamin D levels in men either with or without prostate cancer.”
Scientists examined data collected from a diverse group of more than 600 men from the Chicago area who had elevated PSA levels or other risk factors for prostate cancer. Each man was screened for vitamin D deficiency before undergoing a prostate biopsy.
The authors were surprised to find that vitamin D deficiency seemed to be a predictor of aggressive forms of prostate cancer diagnosis in African-American and European-American men, even after adjusting for potential confounders, including diet, smoking habits, obesity, family history, and calcium intake.
“These men, with severe vitamin D deficiency, had greater odds of advanced grade and advanced stage of tumors within or outside the prostate,” Murphy says.
European-American men and African-American men had 3.66 times and 4.89 times increased odds of having aggressive prostate cancer respectively and 2.42 times and 4.22 times increased odds of having tumor stage T2b or higher, respectively.
African-American men with severe vitamin D deficiency also had 2.43 times increased odds of being diagnosed with prostate cancer.
“Vitamin D deficiency is more common and severe in people with darker skin and it could be that this deficiency is a contributor to prostate cancer progression among African-Americans,” Murphy says. “Our findings imply that vitamin D deficiency is a bigger contributor to African-American prostate cancer.”
Unless it is severe, vitamin D deficiency is fairly asymptomatic, so more effort needs to be put on screening, Murphy says.
“It is a good idea to get your levels checked on a yearly basis. If you are deficient, you and your doctor can make a plan on how to reverse it through diet, supplements, or other therapies.”
The National Institutes of Health and the US Department of Defense funded the study.