Is comprehensive genetic testing worth it for patients with cancer?

Comprehensive gene panel testing, one of the exciting new tools in cancer diagnostics, warrants greater scrutiny — as does a federal program aimed at speeding up the review process for proposed new medical technologies. Those are conclusions of Yale medical experts who studied both and published a report in the Journal of the National Cancer Institute on Sept. 18.

“Over the past decade, we have seen tremendous technological leaps forward in the realm of genetic testing and cancer,” said senior author Dr. Cary P. Gross, professor of medicine and of epidemiology, and director of Cancer Outcomes, Public Policy and Effectiveness Research (COPPER) Center, part of Yale Cancer Center at Yale School of Medicine.

“We can now test a tumor sample for hundreds of genetic mutations at a time,” Gross said. “In some ways, our ability to develop powerful new testing technologies has leap-frogged ahead of our ability to determine whether they are helping people. This is a particularly important issue now, because new genetic tests are being developed not only for patients with cancer, but as an approach to screening healthy patients.”

In the report, the Yale researchers evaluated 113 peer-reviewed scientific studies cited in support of the Centers for Medicare and Medicaid Services (CMS) decision to follow the Food and Drug Administration (FDA) in approving a new genomic profiling platform. CMS approval meant it would cover comprehensive genomic profiling as part of treatment for Medicare beneficiaries, as it outlined in its National Coverage Determination Memorandum.

Gene panel tests are meant to help clinicians understand the unique genetic makeup of a person's cancer in the hopes of informing decisions about the most effective treatments.

“We found that in this initial assessment of comprehensive genetic testing undertaken by CMS to guide Medicare reimbursement decisions, that there was a paucity of studies that closely assess the impact of genomic testing on patient outcomes,” said Gross. “For instance, when we reviewed the literature underlying the Medicare decision to provide reimbursement for these complex sequencing tests, only one compared the outcome of patients who received the test with those who did not.”

In all, the analysis found substantial variability in study designs and a relatively small number of patients included in each study. Moreover, only a handful of studies used the specific gene panel tests that were being evaluated for reimbursement. The researchers concluded that “the variation in the size and type of genetic panels used across studies made extrapolation of the supporting evidence to any specific comprehensive genomic profiling platform challenging, a concern that other researchers have echoed.”

Lead author Sydnie Stackland stated, "We think these findings are particularly relevant, given that comprehensive genomic profiling is becoming more popular year-over-year despite uncertainties in whether the ubiquitous use of these tests is positively impacting patient care."

Beginning in 2011, CMS and the FDA were permitted to review medical technologies simultaneously as part of a parallel review process, instead of one after the other, in an attempt to put new technologies into the marketplace faster. So far, two technologies have been approved by the agencies. Yale researchers say future studies should look into the potential benefits and drawbacks of this approval process, and genomic profiling in general, related to patient outcomes.

The study team also included Michaela Dinan, an associate professor of epidemiology at Yale School of Public Health and co-leader of the Cancer Prevention and Control Research Program at the Yale Cancer Center.