The researchers, from Universities of Bristol and Exeter, noted the condition — called hypercalcaemia — is the most common metabolic disorder associated with cancer, occurring in 10-20 percent of people with the disease. While its connection to cancer is well known, the new study is the first to show that often it can predate the diagnosis of cancer in primary care.
 

The research, published in the British Journal of Cancer, is based on analysis of electronic medical records of 54,000 patients who had elevated levels of calcium and how many of them went on to receive a cancer diagnosis.
 

"All previous studies on hypercalcaemia and cancer had been carried out with patients who had already been diagnosed with cancer - hypercalcaemia was seen as a late effect of the cancer,” said lead researcher Fergus Hamilton, M.D., from the Centre for Academic Primary Care at Bristol. “We wanted to look at the issue from a different perspective and find out if high calcium levels in blood could be used as an early indicator of cancer and therefore in the diagnosis of cancer.”
 

The results showed that, in men, 81 percent of the cancer associated with hypercalcaemia was caused by lung, prostate, myeloma, colorectal, and other cancers. In women, cancer was much less common.
 

“We were surprised by the gender difference,” Dr. Hamilton said. “There are a number of possible explanations for this but we think it might be because women are much more likely to have hyperparathyroidism, another cause of hypercalcaemia. Men rarely get this condition, so their hypercalcaemia is more likely to be due to cancer.”