Illustration: Maja Moden
At least 10 percent of all cancers — still one of the leading causes of death among Americans — are caused by inherited mutations in genes such as BRCA1 and BRCA2. Parents with the cancer gene mutation have a 50 percent chance of passing it on to a son or daughter.
It is well-known that women with BRCA are at a very high risk for breast and ovarian cancers. Less known is that men with these mutations also are at risk for breast and other cancers. A new UCLA study has found that few men are screened for these genetic mutations; the researchers strongly recommend that they be screened.
“If a male has a BRCA mutation, his risk of breast cancer increases a hundredfold,” says Christopher Childers, MD, a resident in the UCLA Department of Surgery and the paper’s senior author. “BRCA mutations also put men at higher risk for often aggressive prostate cancers that occur at younger ages. These mutations also have been associated with other cancers, such as pancreatic cancer and melanoma,” he says.
This may be the first national study to analyze the rates of genetic cancer testing for both men and women, Dr. Childers says. Analyzing data from the 2015 National Health Interview Survey, researchers found that nearly 2.5 million people underwent cancer genetic testing. This includes testing for genes related to breast/ovarian cancer such as BRCA, as well as those related to risk for colorectal and other cancers. Of the 2.5 million people, nearly three times as many women received testing compared with men — 73 percent vs. 27 percent.
The researchers also found that the disparity in testing was specific to breast/ovarian cancer. Men underwent testing for breast/ovarian cancer genes at one-tenth the rate of women. There was no gender disparity for colorectal or other cancer testing. Fewer Latinos, uninsured, non-citizens and residents with less education received genetic testing compared with the rest of the population.
The next steps are to determine why so few men are tested and to find ways to increase those rates, says Kimberly Childers, regional manager of the Clinical Genetics and Genomics program at Providence Health & Services Southern California and the paper’s lead author. “Previous studies have shown that men don’t necessarily understand the importance of a breast cancer gene mutation — that it is more of a ‘feminine’ issue — but this couldn’t be further from the truth,” she says. “We hope this study will spur broad national educational efforts.”
“National Distribution of Cancer Genetic Testing in the United States: Evidence for a Gender Disparity in Hereditary Breast and Ovarian Cancer,” JAMA Oncology, April 26, 2018.