Members of families with a history of certain cancers may miss out on potentially life-saving screening tests or treatment because many forego genetic testing to estimate their cancer risk, according to researchers in France.
Investigators from cancer centers throughout France analyzed data from patients who were referred between 2003 and 2011 because of an increased risk of breast or colorectal cancer. Records from 240 134 consultations and 134 652 genetic tests showed that tests to detect mutations in the BRCA1 and BRCA2 genes that increase risks for breast and ovarian cancers more than tripled, from 2095 in 2003 to 7393 in 2011.
But the data showed only a modest increase in testing to detect genetic mutations linked with Lynch syndrome, which increases the risk of colorectal and other cancers. Abnormalities in genes known as MMR, which help repair damaged DNA, confer the increased risk for Lynch syndrome. The data showed that tests to detect MMR mutations increased by about 43%, from 1144 in 2003 to 1635 in 2011.
“While the increase in BRCA testing is encouraging, it is far from optimal,” Pascal Pujol, MD, head of the cancer genetics department at Montpellier University Hospital, said in a statement. He called the figures for MMR mutation testing “frankly disappointing.” Pujol will present the data this weekend in Paris at the European Society of Human Genetics’ annual meeting.
“Given that [genetic] testing can provide many options to enable individuals to manage their cancer risk, it is vital to encourage awareness and acceptance among both the public and medical professionals,” Pujol added.
He noted that women aged 40 years or older with a BRCA mutation can reduce their risk of ovarian cancer by 20% if they have their ovaries removed. Prophylactic mastectomy can reduce the risk of breast cancer by about 90% in women with a BRCA mutation. But surgery isn’t the only option. Physicians can monitor women at high risk for breast cancer with regular magnetic resonance imaging scans.
Similarly, Lynch syndrome confers a 45% increased risk of developing colorectal cancer by age 70 years; women with the syndrome also have an increased risk for endometrial and ovarian cancers. “For familial colon cancer, screening by colonoscopy has been shown to decrease mortality,” Pujol added.
The data that he and his collaborators analyzed are only from France. But Pujol said they believe that similar trends could be found in many other countries. “It is extremely worrying that such a simple test, which has the potential to spare whole families from devastating illness, is being so underused,” he said.