As more potential tumor biomarkers are identified to help diagnose cancer and determine treatment, it becomes increasingly important to ensure that these markers are reliable and relevant.
Researchers at the University of Michigan Comprehensive Cancer Center urge more rigorous evaluation of tumor biomarkers. Daniel F. Hayes, M.D., clinical director of the breast oncology program and newly elected president of the American Society of Clinical Oncology, explains.
You have referred to tumor biomarkers as caught in a “vicious cycle.” What do you mean by that?
Hayes: Biomarkers are not valued nearly to the extent that we see with therapeutics. Regulatory rules are inconsistent, third-party payment is inadequate and tumor biomarker research is underfunded. All this combines to create a vicious cycle that prevents development and testing of reliable biomarker tests that could be used to personalize clinical care of patients with cancer.
If a tumor biomarker test is used to decide whether a patient should receive a certain treatment, then it is as critical for patient care as a therapeutic agent. A bad biomarker test is as dangerous as a bad drug.
What makes a biomarker test good?
Hayes: First, a biomarker test must have analytical validity. We need to know it is accurate, precise, reliable and reproducible. In addition, it must have clinical validity. A biomarker needs to divide a population into two or more groups based on differences in biology or a certain clinical outcome. Clinical validity also means that we need high levels of evidence that when used to determine treatment, a biomarker test improves the patient’s outcome or delivers equivalent care at a lower cost.
What do you recommend?
Hayes: My colleagues and I have made several transformative recommendations to break the vicious cycle:
- Reform regulatory review of tumor biomarker tests
- Increase reimbursement for tumor biomarker tests that are proven to help determine which therapies will or are working
- Increase investment for tumor biomarker research so it is comparable to new drug research
- Increase the rigor for peer review of tumor biomarker publications
- Include only proven biomarker tests in evidence-based care guidelines
These recommendations are not about creating more regulation; they are about creating an even playing field that allows tumor biomarker tests to be developed and proven clinically relevant. We want to stimulate innovation yet hold investigators and clinicians to the highest scientific standards – as we now do for therapeutics. We need to change the way we value tumor biomarkers in this country.