Randomized Clinical Trial Led by University Hospitals Seidman Cancer Center Oncologist Leads to Practice-Changing Precision Prostate Cancer Therapy

• Randomized trial validates first biomarker tool to guide hormone treatment decisions, allowing for more personalized prostate cancer care
• Patients with a prostate tumor subtype known as luminal B had much lower risks of recurrence and metastasis when radiation was complemented by apalutamide
• First-of-its-kind genomic test (PAM50), Decipher Enabled Biomarker by Veracyte, determines prostate cancer subtype
• Once subtype is determined by test; treatment can be personalized
• Originally developed to guide breast cancer treatment and adapted to capture prostate cancer biology by Dr. Spratt and his colleagues
• Results of the BALANCE trial (NRG Oncology GU006) was presented at the American Society for Radiation Oncology (ASTRO) Annual Meeting by principal investigator Dr. Daniel Spratt, Chair radiation oncology, Associate Chief Scientific Officer, UH Cleveland Medical Center and Vincent K. Smith Chair in Radiation Oncology

CLEVELAND, Ohio – A major finding in the world of prostate cancer was announced at the American Society for Radiation Oncology (ASTRO) conference by principal investigator, Daniel Spratt, MD, Chair Radiation oncology at University Hospitals Seidman Cancer Center and Vincent K. Smith Chair in Radiation Oncology.

The new randomized study, led by Dr. Spratt, found a lab test that reads tumor genes can identify which patients with recurrent prostate cancer will benefit from adding hormone therapy to radiation after surgery — the first predictive biomarker in this setting.

Patients with a prostate tumor subtype known as luminal B had much lower risks of recurrence and metastasis when radiation was complemented by apalutamide, a type of hormone therapy. Patients without this tumor subtype, however, saw no improvement.

“We’ve been searching for decades for a way to determine which patients are most likely to respond to hormone therapy after prostatectomy,” said Dr. Spratt. “We now have a tool that lets us tailor treatment based on a tumor’s biology, and can recommend hormone therapy only for those patients who we think can expect to see a benefit.”

Prostate cancer patients have several treatment options including definitive radiation therapy or surgical removal of the prostate, known as radical prostatectomy. But for up to 30% of patients, the disease will recur or persist, often signaled by rising prostate-specific antigen (PSA) levels. For patients with a rising PSA level after prostatectomy, radiation therapy is the standard treatment and has been shown to improve survival.

Hormone therapy is commonly added to radiation in this setting to block or reduce testosterone, a hormone that fuels prostate cancer growth. While it can enhance the effects of radiation and improve cancer control for some patients, it also carries a wide range of side effects, including fatigue, bone loss, hot flashes, metabolic changes and cardiovascular risk.

“Testosterone is important for maintaining bone, muscle, cognitive and cardiac health, but it’s also the key fuel driving prostate tumors,” said Dr. Spratt. “Until now, we haven’t had a reliable way to tell who really needs hormone therapy and who does not.”

The answer came from PAM50, a gene expression test that was originally developed to guide breast cancer treatment and adapted to capture prostate cancer biology by Dr. Spratt and his colleagues Felix Feng, MD, FASTRO, and Shuang Zhao, MD.

Prostate tumors, like breast tumors, can be grouped into molecular subtypes; in this study, tumors were classified as either luminal B or non-luminal B. Luminal B tumors grow more quickly and are highly responsive to hormone therapy. Non-luminal B tumors, including luminal A and basal-like subtypes, are generally less dependent on testosterone and may not respond to hormone-based treatment. Dr. Spratt compared the advance to breast cancer, where estrogen receptor status helps guide endocrine therapy decisions.

Dr. Spratt said he believes the findings will be practice changing.

“This is the first prospectively validated predictive biomarker in prostate cancer,” he said. “It gives us a promising way to personalize care, recommending hormone therapy for those who respond, and avoiding unnecessary treatment when it is unlikely to help.”

*This press release is based on original copy from ASTRO. Complete release and presentation found here.