• 9/1/2005
  • Linda Geddes
  • NewScientist.com

Men carrying a genetic mutation that significantly increases the risk of breast cancer in women are at a greater risk of prostate and pancreatic cancers than men without the mutation.

Dutch researchers have confirmed that men carrying a mutated BRCA2 gene are twice as likely to develop prostate cancer and six times more likely to develop pancreatic cancer than those free of the mutation. The altered gene may also put them at increased risk of developing bone and throat cancer.

A previous study suggested that carriers of mutant BRCA2 genes are at increased risk of cancer of the prostate, pancreas, gallbladder, bile duct and stomach, as well as malignant melanoma, breast cancer and ovarian cancers (Journal of the National Cancer Institute, vol 91 p 1310). But this study only looked at known mutated-BRCA2 carriers with a strong family history of breast or ovarian cancer.

Christi van Asperen and her colleagues at the Centre for Human and Clinical Genetics at Leiden University in The Netherlands speculated that estimates of cancer risk at other sites in the body may differ in mutated-BRCA2 carriers with less striking , though still present, family histories of cancer.

Retrospective incidence
They investigated 139 families with 66 different mutations of the BRCA2 mutation between them. Using information from known mutated-BRCA2 carriers in these families, the researchers studied the retrospective incidence of cancers among both male and female family members with a 50% chance of being a carrier – amounting to 1811 people.

Among the study group, a subgroup of 441 people had already been tested for BRCA2. From this subgroup the team found that, on average, 52% of mutation-carriers developed cancer, compared with just 13% of non-carriers. And in those carrying the BRCA2 mutation, there were higher numbers of prostate, pancreatic, throat and bone cancers than would be expected in the general population.

Almost all of the increased risks for these cancers were statistically significant for men only, and tended to be stronger for people under the age of 65.

“This study confirms previous findings that men carrying the BRCA2 mutation are at higher risk of developing prostate and pancreatic cancer,” says van Asperen. “This means we should perhaps consider including male carriers in high risk screening programmes for prostate cancer, although we will have to decide the best way of doing this.”

Source:
Journal reference: Journal of Medical Genetics (vol 42, p 711)