A study led by UCLA Health has shown that PSMA-PET imaging can detect hidden metastases in nearly half of high-risk prostate cancer cases previously classified as nonmetastatic, challenging past assumptions and suggesting new treatment strategies.
Researchers led by the University of California, Los Angeles (UCLA) have uncovered a groundbreaking method to detect hidden metastases in high-risk prostate cancer patients. In a new study, almost half of the cases initially identified as nonmetastatic by conventional imaging were found to have metastatic disease when assessed with advanced prostate-specific membrane antigen–positron emission tomography (PSMA-PET).
The study, published in JAMA Network Open, suggests that traditional imaging may underestimate the extent of cancer spread in many high-risk, nonmetastatic prostate cancer cases.
“Our study demonstrates the critical role of PSMA-PET in accurately staging prostate cancer, which can significantly impact treatment decisions and outcomes,” senior author Dr. Jeremie Calais, a director of the Ahmanson Translational Theranostics Division’s clinical research program and an associate professor in the department of molecular and medical pharmacology at the David Geffen School of Medicine at UCLA, said in a news release.
PSMA-PET imaging employs radiotracers that bind to prostate cancer cells, rendering them visible on PET scans. Unlike traditional imaging methods, which only provide anatomical details, PSMA-PET offers functional imaging that highlights the cancer’s biological activity, enhancing the accuracy of disease staging.
The clinical adoption of PSMA-PET has revolutionized prostate cancer imaging. However, treatment decisions often rely on clinical trials that did not utilize this advanced technology for patient selection.
To delve deeper into the advantages of PSMA-PET over conventional imaging, researchers conducted a retrospective study with data from 182 high-risk recurrent prostate cancer patients. These patients, previously considered to have cancer confined to the prostate based on traditional imaging, were initially deemed eligible for the EMBARK trial. This trial showed that adding enzalutamide, a type of hormone therapy, to androgen deprivation therapy significantly improved metastasis-free survival.
The researchers, however, now believe conventionally classified nonmetastatic patients might have had more advanced disease.
Intriguingly, PSMA-PET detected cancer metastases in 46% of the patients, revealing the extent of disease that conventional imaging missed. Furthermore, 24% of the patients displayed five or more metastatic lesions.
“We anticipated that PSMA-PET would detect more suspicious findings compared to conventional imaging. However, it was informative to uncover such a high number of metastatic findings in a well-defined cohort of patients resembling the EMBARK trial population that was supposed to only include those without metastases,” added first author Dr. Adrien Holzgreve, a visiting assistant professor at the David Geffen School of Medicine.
These findings challenge the interpretation of previous studies and underscore the importance of incorporating PSMA-PET in clinical trial patient selection and treatment strategies. The study opens the door to potentially curative options like targeted radiotherapy and raises important questions about integrating new imaging technologies into standard care.
Further research is vital to understand PSMA-PET’s impact on long-term patient outcomes and to refine its application in guiding therapy.
“We have good rationales to assume that it is helpful to primarily rely on PSMA-PET findings,” Holzgreve added. “But more high-quality prospective data would be needed to claim superiority of PSMA-PET for treatment guidance in terms of patient outcome.”
As PSMA-PET continues to reshape prostate cancer staging and guide personalized therapies, its integration into clinical practice could significantly improve outcomes for patients with high-risk prostate cancer.