Many parents of cancer patients could get genetic tests if the price is right

(Reuters Health) – Cancer patients' close relatives may be willing to get tested to see if they share genetic mutations that expose them to tumors, if the tests were accessible and affordable, suggests an American experiment.

The researchers asked 741 people with one of the 30 mutations associated with cancer and 360 "first degree" parents – a parent, a brother or a child – to invite other relatives parents to sequence their genes for around $ 50 – about a tenth of the standard cost.

In total, these individuals invited 2,280 first-degree relatives to pass the genetic tests.

In the first year of the remission test program, 48% of the invited parents agreed to take a test. About 48% of these first-degree relatives tested positive for the same cancer-related genetic mutation in a family member, and about 5% had a different variant associated with tumors, according to the study.

Then, 12% of those parents who tested positive went on to cascade tests by inviting other family members to take tests.

"Cascade genetic testing – where relatives of people with a genetic mutation are tested to determine if they are also carriers – is one of the best ways to identify carriers and carriers." to reduce their risk, "said lead author Jennifer Caswell. Jin from the Stanford University School of Medicine in Palo Alto, California.

As a rule, only one-third of the family members get tested, Caswell-Jin said by e-mail.

The current experience is to improve this process by making the process easier and less expensive. People with cancer risk mutations could undertake online testing and let the labs directly contact relatives.

"The best way to identify people at high risk of cancer – which is the first step in reducing their risk of cancer – is to begin by testing the family member most likely to carry a genetic mutation at risk. high risk (for example, a diagnosed person). with cancer at a young age or with multiple cancers), "said Caswell-Jin.

"Our study explores an approach to optimize the testing process of other relatives in the family once a person has been tested positive for a cancer risk mutation," Caswell-Jin said.

Although cancer-related mutations do not affect everyone, knowing that you're a carrier can help people and their physicians make informed decisions about health care while they're still healthy . Institute.

For example, women with BRCA1 or BRCA2 mutations, who have a significantly increased risk of developing breast or ovarian cancer, may choose to have a mastectomy or remove their ovaries even without a diagnosis of cancer. Other types of mutations, such as those that increase the risk of colon cancer, may indicate the need for more frequent or frequent screening.

One of the limitations of the study is that researchers only followed people for a year, and it is difficult to know how many parents have been tested for cancer.

This type of test is often not covered by insurance and can cost hundreds of dollars.

"A major question is how results influence health decisions, and people need clinicians to manage the growing complexity of this landscape," said Dr. Steven Katz, a health policy researcher at the University of Ottawa. 39, University of Michigan Ann Arbor. involved in the study.

"The direct harm to patients and loved ones is that inaccurate test results could lead to nullifying unjustified concerns or procedures," Katz said by email. "But emerging evidence suggests that this has not been the case so far."

Testing can be less risky when genetic counselors can help patients make the decision to be screened for positive or negative results, said Dr. Lisa Newman, Chief of Breast Surgery at Weill Cornell Medicine / New York. Network of Presbyterian hospitals in New York.

"Parents who undergo genetic testing and who carry the mutation may choose to pursue prevention strategies to reduce their risk of cancer, or they may adopt improved cancer screening practices for the early detection of the disease." the study, said by email. "However, they will not have any of these choices if they are not aware of the risk of familial / hereditary cancer."

SOURCE: bit.ly/2xhTzjq Journal of the National Cancer Institute, online September 17, 2018.