According to scientists, the new findings suggest that a simple blood test may identify men at high risk for the most dangerous prostate tumours, and there already are drugs available that cut calcium levels in the bloodstream.
To reach the conclusion, the researchers tracked 2,814 men in a government health survey in which they gave blood samples that revealed calcium levels.
The study found that the men in the top third of blood calcium levels had 2.68 times the risk of developing fatal prostate cancer later in life compared to those in the bottom third.
"If serum calcium really does increase your risk for fatal prostate cancer, that's wonderfully exciting because serum calcium levels can be changed," the Mirror quoted Gary Schwartz of Wake Forest University School of Medicine, who helped lead the study, as saying in a telephone interview.
"One way to think of it is to think of the tremendous advances in the control of cardiovascular disease that occur from understanding that things like serum cholesterol predict heart attack," Schwartz added.
Doctors have struggled to find ways to predict if a man who gets prostate cancer will have a tumour that poses little danger, as is often the case, or one that is a killer.
Blood calcium was not very predictive of whether a man would get nonlethal prostate cancer, but was highly predictive of whether a man would get a fatal case, the researchers wrote in the American Association for Cancer Research's journal Cancer Epidemiology, Biomarkers and Prevention.