Use of the anti-diabetic drug metformin may be associated with lower chances of being diagnosed with disseminated colorectal cancer
A new paper published in the journal Cancer Epidemiology, by researchers at Trinity College Dublin and the National Cancer Registry, reports that people who take the anti-diabetic drug metformin may be less likely to present with disseminated colorectal cancer.
Laboratory-based research has suggested that certain types of drugs used by people who have diabetes, such as metformin, may prevent cancer cells from spreading. Metformin use has also been linked to improved survival in people with colorectal cancer. In a study funded by the Irish Cancer Society, the research team combined Registry data on people diagnosed with colorectal cancer and community prescribing information from the Primary Care Reimbursement Service (PCRS) to investigate whether using different types of anti-diabetic drugs was associated with how far the cancer has spread at the time of diagnosis.
The analysis compared two groups of people with colorectal cancer: those who took metformin before diagnosis and those who took other anti-diabetic drugs. The research team found that the chance of being diagnosed with a cancer that had spread around the body (disseminated disease), as compared to a cancer that was confined to the site of origin, was 34% lower among those using metformin. The effect was even stronger among people who were taking metformin every day and those who used metformin and no other anti-diabetic drugs.
Disease spread at diagnosis is a major predictor of survival. Therefore, the team concluded that further investigation of the potential association between metformin use and disease spread among larger groups of cancer patients is needed.