Breast cancer diagnostic test has Utah roots
Aug 14, 2026
Read Time: 3 Minutes
Philip Bernard, MD
Takeaways: The PAM50-based Prosigna test accurately identifies some high-risk breast cancer patients that can safely forego chemotherapy and receive hormone therapy alone.The PAM50/Prosigna test originated from research led by Philip Bernard, MD, at Huntsman Cancer Institute. Impact: Prosigna and the OPTIMA trial highlight the value of precision medicine. By tailoring treatment to a patient's specific cancer biology, physicians can reduce toxicities associated with unnecessary therapies and maintain positive outcomes.
Chemotherapy is a common form of treatment for many high-risk breast cancer patients. These drugs effectively target cancer cells and can be a lifesaving therapy. But they also damage healthy cells, leading to side effects such as hair loss, nausea, low blood cell counts, and nerve damage. Emerging evidence shows that patients with certain kinds of breast cancer can avoid chemotherapy and still have positive treatment outcomes—thanks to research that has its roots at Huntsman Cancer Institute at the University of Utah (the U).
Earlier this summer, oncologists from around the globe gathered for the Annual Meeting of the American Society of Clinical Oncology (ASCO). At the conference, physician-scientists presented the latest clinical research that is driving progress in cancer care, discovery, and patient outcomes.
One of the presentations centered on the final results from the OPTIMA Phase 3 trial, which found that patients with estrogen-receptor positive (ER+), HER2 negative breast cancer can use a gene expression test called Prosigna (PAM50) to determine if they can safely avoid chemotherapy. OPTIMA enrolled over 4,000 patients with high-risk breast cancer to receive either standard chemotherapy followed by hormone therapy or Prosigna-guided therapy. Patients who elected to forego chemotherapy based on the results of the test had similar outcomes to women receiving chemotherapy as a standard of care.
"Behind every breast cancer treatment decision is a patient asking, 'Do I really need chemotherapy?'" says Robert Stein, MBBS, PhD from the University College London Hospitals Biomedical Research Centre and lead OPTIMA investigator, in a press release. "OPTIMA answers this question with robust evidence. These study results can be practice-changing—we can now use the Prosigna test to predict which high-risk patients can safely avoid chemotherapy and its lasting side effects without compromising outcomes. That is a profound shift for patients and the clinicians who care for them."
“It was an incredible return of all that effort that we had put in so long ago. Our work showed that we could spare chemotherapy for two-thirds of breast cancer patients, which will make a big difference in their lives.”
A Risk Score Based on Biology
The story of Prosigna began with researchers at Huntsman Cancer Institute over two decades ago. Philip Bernard, MD, Huntsman Cancer Institute investigator and adjunct professor of pathology at the U, pivoted early from his conventional medical training to focus on research that would translate into better patient care.
He and his colleagues were particularly interested in why women with similar stages of disease and biomarker status could have very different survival outcomes. Biomarkers are molecular signatures that can be used to diagnose, predict outcomes, or treat a disease.
At the time Bernard started his research, physicians were using only a few key biomarkers—including if tumors were driven by estrogen, progesterone, or by the growth protein HER2—for prognosis and therapy selection. Bernard wanted to investigate what other genes may be involved in breast cancer biology that could help with diagnosis and ultimately guide treatment.
Inventors involved with the development of the Prosigna test at the Breast Cancer Intergroup strategic summit, National Institutes of Health. From left to right: Torsten Nielsen, MD, PhD, (University of British Columbia), Philip Bernard, MD, (University of Utah), Matthew Ellis, MD, PhD, (then at Washington University in St. Louis) and Chuck Perou, PhD (University of North Carolina at Chapel Hill). Photograph taken Feb 24, 2009.
In 2005, he and colleagues from the University of British Columbia, Washington University, and the University of North Carolina received a large multi-institutional grant from the National Cancer Institute to develop a diagnostic test for breast cancer.
Their work culminated in the PAM50, a standardized set of 50 genes that could identify breast cancer’s intrinsic subtypes. These are biological markers that can indicate the aggressiveness of the disease. They also created an algorithm that could be used to determine the risk of cancer recurrence, or return, based on the PAM50 genes.
“Our prognostic model was based on these subtypes of breast cancer. It was a risk score based on the biology,” says Bernard.
Bernard co-founded BioClassifier, a U spinoff company, to commercialize the test. The OPTIMA trial ultimately enabled Prosigna to be tested prospectively in a real-world clinical setting. Bernard was in the audience at ASCO when lead investigator Stein presented the results.
“The experience was surreal. Seeing the result of what became a 20-year experiment was very moving, especially since the outcome of the study was unknown to us. I got goosebumps,” says Bernard. “It was an incredible return of all that effort that we had put in so long ago. Our work showed that we could spare chemotherapy for two-thirds of breast cancer patients, which will make a big difference in their lives.” Bernard and his colleagues receive royalties on the sales of the Prosigna test.
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