have been cleared by the FDA. These are very commonly ordered assays, yet there is limited evidence that the results of these tests offer any clinically useful information for most people.

Dan Hayes responded that tests are often ordered because they are available and easy to order and there is little cost to the doctor for using them inappropriately. Physicians order marker tests as part of general data gathering about the patient. “A bad marker is as bad as a bad drug,” he said, adding that providers are making critical treatment decisions based on information that may be wrong. Practitioners could do much better in not overtreating patients who will not benefit and in identifying patients who will benefit. This is where marker development is as important as pharmaceutical development, Hayes said. Becker added that the idea of being able to manage clinical effect (e.g., the hoped-for effect against a tumor or the range of adverse events) is something that lies in the realm of clinical practice. It is a matter of judgment and experience. The question in the mind of a clinician deciding whether to adopt a new test is, What does it add to what is already done in day-to-day practice? Hayes added that clinicians are sometimes of the opinion that practice guidelines are made without considering individual patients and the nuances that come with each. Such contextual issues are difficult to build into the guidelines.

One approach that could affect practice would be for third-party payers who agreed to cover a genomic diagnostic test to then deny coverage of a treatment if the provider treated the patient differently than what the test result had directed (but only if the recommendations from the results are clear cut). Blue Cross and Blue Shield plans, for example, do not pay for trastuzumab treatment for a HER2-negative patient because such a test result indicates it is not a medically appropriate treatment. However, some participants said, this approach does raise concerns about patient autonomy and about patients’ rights to change their minds on treatment course in certain circumstances.

HETEROGENEITY OF EVIDENCE-BASED DECISIONS

Moderator Sharon Terry of Genetic Alliance pointed out the variation in evidence-based decisions. For example, FDA recently cleared the breast cancer recurrence test, MammaPrint, for more broad use in all age groups, while the Blue Cross and Blue Shield Association TEC determined that Oncotype DX met its criteria but MammaPrint did not, and EGAPP has concluded there is insufficient evidence to recommend for or against either test.

Piper responded that the Oncotype DX test was reviewed by TEC several times, and the final vote to cover the test was very close. Similarly,



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