Editor’s note: This article was updated to reflect changes requested by a source.
Because prostate cancer has a long natural history, decision-making about systemic therapy that could be informed by treatment response–predicting biomarkers can come several years after initial diagnosis, noted Himisha Beltran, MD, a medical oncologist and researcher specializing in genitourinary cancers at Weill Cornell Medicine and its Institute for Precision Medicine in New York, New York.
“A lot of the biomarker work has been to try to figure out which patients will respond to these drugs or additional, newer drugs designed to target the androgen receptor,” Dr Beltran told Cancer Therapy Advisor.
Given that male sex hormones fuel prostate tumor growth, androgen receptor (AR) mutations and amplifications are frequently involved in acquired tumor resistance to initial androgen-targeting treatment. Yet there is emerging evidence — preclinical thus far — that RB1 and p53 mutations drive androgen resistance, Dr Beltran noted.1
Detecting tumors’ acquisition of these mutations in liquid biopsies of circulating tumor DNA could allow more timely shifts to other treatment options. Liquid biopsies could also open up management of metastatic prostate cancer to more precise treatment decision-making.
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Working with the Stand Up to Cancer-Prostate Cancer Foundation Dream Team, Dr Beltran has helped examine tumor biopsy DNA and RNA from 150 men with metastatic castration-resistant prostate cancer (mCRPC) to identify candidate molecular biomarkers for identifying treatment outcomes. The team plans to sequence tumors and follow 500 patients with prostate cancer over the coming few years. These tools could help with more accurate patient risk stratification, matching patients to the best treatments, and inform patients and family members about potential inherited genetic risk factors.2,3