Get a Cancer Gene Test? A Tool for Helping to Decide

Genetic testing for cancer is well established, but a new online tool would help patients and providers decide whether a test
is warranted.

PREMMplus, developed by researchers and physicians at
Dana-Farber Cancer Institute, screens patients who may benefit from genetic testing to determine whether they carry inherited genes that increase their risk of getting cancer.

“One of the problems with genetic testing is it’s out there but a lot of people still aren’t getting it,” says Sapna Syngal, M.D., M.P.H., director of research at the Center for Cancer Genetics and Prevention at Dana-Farber Cancer Institute in Boston. “Part of the reason for that is it takes a lot of time for doctors to get the family history.”

PREMMplus automates a way to collect people’s personal and family cancer history and figures out who needs to be referred for genetic testing, says Syngal.

The software uses answers to medical and family history questions to calculate the probability that a person carries an inherited mutation in any of 19 genes associated with 18 cancers. Syngal said a patient with a score above 2.5% should seek genetic testing. “It’s really a triaging of getting (genetically) tested (for cancer),” she says.

The algorithm was based on data from 7,280 adults who underwent testing for hereditary cancer risk at Dana-Farber’s Genetics Program.

Syngal and her colleagues reported favorable sensitivity results for algorithm in the Journal of Clinical Oncology in August.

Other prediction tools are available, but they provide estimates for particular genes or hereditary syndrome, says Heather Thompson Mackey, a senior director of cancer prevention and early detection at the Prevent Cancer Foundation in Alexandria, Virginia.

Mackey says it is “highly encouraging” that published results study show that the PREMMplus tool had high sensitivity. “It similarly had a high negative-predictive value, which means that when a person was predicted to not have the inherited changes, that genetic testing was negative,” she says.

However, Mackey notes that predictive software such as
PREMMplus could give people a false sense of security.

“It is important to remember that a person who undergoes genetic testing and is not found to have a genetic predisposition still can develop cancer,” Mackey says. “Only 5% to 10% of cancers are hereditary, meaning the vast majority of cancers arise for reasons other than inherited genetic mutations.” PREMMplus is a tool that could be embedded into the electronic medical record systems and sent out to patients before their appointments, Syngal says.

Anu Antony, M.D., chief medical officer of SimBioSys Inc., says that incorporating technology into the decision-making process offers a valuable approach to help guide physicians and could potentially save patients time and money. Insurance coverage of genetic screening depends on meeting certain requirements, and patients may therefore spend up to $250 out-of-pocket for a single genetic test, she says. Quickly assessing whether genetic testing is likely to be informative in the first place could mean a considerable cost savings for patient, notes Anthony.

An online version of the tool will be operational by the end of this year, and individual patients can get their scores on the Dana-Farber website free of charge. Healthcare systems will be required to take out a license from Dana-Farber, and the price they pay will depend on the volume of patients and the type of institution.