Aggressive prostate cancer linked to breast cancer gene mutation

Men with prostate cancer are at increased risk of having an aggressive tumour if they also carry a gene mutation normally linked to breast cancer, U.S. researchers say.

The findings could have implications for treatment prostate cancer patients with the mutation might opt against "watchful waiting," in which the tumour's growth is monitored but not treated.

They may instead decide to have surgery or radiation treatments.

"One of the biggest problems with early-stage prostate cancer is being able to distinguish between tumours with the potential to become aggressive and those that may persist for many years without enlarging or spreading," Dr. Robert Burk, senior author of the study, said in a release.

Burk is with the Albert Einstein College of Medicine of Yeshiva University in New York.

The study, published in Friday's Clinical Cancer Research journal, examined 979 men with prostate cancer and 1,251 men without the disease.

Researchers looked at whether the men carried mutations for either of two genes, BRCA1 and BRCA2. Scientists have known for some time that women carrying these mutations are at increased risk of breast cancer, ovarian cancer, or both.

The study included only men of Ashkenazi Jewish descent because they are five times likelier than people in the general population to carry a mutation in the BRCA1 or BRCA2 genes. Ashkenazi Jews originated in Germany's Rhineland.

Researchers found that while mutations did not increase a man's risk of prostate cancer, those who already had it weremuch more likely tohave an aggressive tumour.

Specifically, study participants with aggressive tumours were 3.2 times more likely to carry the BRCA2 gene mutation than were men in the control group.