Mutations in BRCA1 and BRCA2 genes increase the risk of breast cancer but may also cause prostate and pancreatic cancers in men, Cambridge University scientists have discovered. After studying the medical history of thousands of families, the team found that 27% of men who carry a BRCA 2 mutation will develop prostate cancer, and those with faulty BRCA 1 and BRCA 2 genes are twice as likely to develop pancreatic cancer than the general public.

BRCA mutations are rare, affecting fewer than 1 in 300 people, but they are a dangerous warning sign for cancer when they do occur. Over 50% of women with BRCA mutations will get cancer before they're 80, and more than 40% will develop ovarian cancer, says the National Cancer Institute. While scientists have suggested BRCA mutations could be linked to other cancers in men, research has been limited – until now.

Cambridge University researchers studied the medical histories of over 5,000 families where one or more family members had a BRCA 1 or BRCA 2 mutation. The team analysed the results to identify correlations or associations with 22 primary cancers.

They discovered that men with a BRCA 2 mutation had a 27% risk of developing prostate cancer before 80. There was no relationship between BRCA 1 mutations and prostate cancer. However, men who had a mutated BRCA 1 or BRCA 2 gene were twice as likely to develop pancreatic cancer in their lifetimes. The findings are an exciting new development in the fight against male cancers and help us understand more about the genetic mechanisms causing cancer.

"We've known for some time that they're linked to breast and ovarian cancer, but there's been uncertainty about other cancers," said co-author Professor Antonis Antoniou. "These large datasets of patients have allowed us to estimate with much greater accuracy the extent to which faulty BRCA1 and BRCA2 genes increase the risk of several cancers,"

In the study, funded by Cancer Research UK and published in the Journal of Clinical Oncology, the team also found that BRCA mutations increase the risk of breast cancer in men. While a rare form of the disease in men, those with BRCA mutations have a 40 in 1,000 chance of developing breast cancer in their lifetime.

The research also answers some outstanding questions and offers some positive news for those with BRCA 2 mutations, says the University of Cambridge's Professor Marc Tischkowitz. "Our data suggests that there is no strong link between BRCA2 and melanoma, which may provide greater clarity to BRCA2 gene carriers."

The findings provide strong evidence of links between BRCA genes and male cancers that could have practical implications for screening, says Tischkowitz. "The results will add to our knowledge on optimising cancer screening and early detection strategies for people who are known to carry these faulty genes."

Genetic testing is the future of cancer diagnosis providing clinicians with critical insights into disease risk, and RGCC is leading the way. Our range of personalised cancer tests can help clinicians understand a patient's risk of developing certain forms of cancer, understand what treatments will be most effective and identify any secondary tumours within the body. They're providing peace of mind and protection for men and women at risk of developing cancer.

You can read the full paper, Cancer Risks Associated With BRCA1 and BRCA2 Pathogenic Variants, here.