(UroToday.com) The 2025 American Society of Clinical Oncology (ASCO) Genitourinary (GU) Annual Symposium held in San Francisco, CA, between February 13–15, 2025, was host to a prostate cancer prostate session. Lufan Wang, MSc, presented the results of a study evaluating the impact of PSMA PET and conventional imaging on contemporary management patterns in patients with biochemical recurrence after radical prostatectomy.
While PSMA PET imaging has been demonstrated to have improved performance characteristics, compared to conventional imaging, for staging intermediate- and high-risk prostate cancer patients in the pre-treatment and biochemically recurrent settings, the impact of the widespread uptake of PSMA PET imaging on clinical decision making and survival outcomes remains unclear. The objective of this study was to assess the early clinical impact of PSMA PET utilization by comparing predictors and rates of salvage treatment (XRT +/- ADT) and second biochemical recurrence (BCR) among those undergoing PSMA PET versus conventional imaging.
The study investigators retrospectively identified 341 patients who experienced BCR post-radical prostatectomy, defined as a PSA ≥0.2 ng/ml with an undetectable PSA post-operatively, who subsequently underwent PSMA PET or conventional imaging between 2010 and 2023. Unadjusted survival analyses were used to describe the incidences of salvage treatment and second BCR, while multivariate Cox proportional hazard models were used to identify independent predictors of each outcome. Chi square analyses were used to compare different salvage therapy modalities between PSMA-PET and conventional imaging.
PSMA PET was associated with higher detection rates, with 53% of patients having positive findings, compared to 10% in those who underwent conventional imaging (median PSA values of 0.24 and 0.25, respectively). A higher frequency of positive findings in the prostate bed (23% versus 15%) and pelvic nodes (39% versus 5%) were observed in those who underwent PSMA PET imaging. Notably, patients underwent salvage therapy at lower median PSA values and within fewer days after initial BCR in the PSMA PET group.
However, there were no differences in salvage therapy or second BCR rates between imaging groups on unadjusted survival analyses.
Predictors of salvage therapy included: log PSA at initial BCR, advanced pathology, and undetectable PSA levels achieved within 6 months of radical prostatectomy.
Predictors of second BCR included: log PSA at recurrence (HR: 1.27, 95% CI: 1.02–1.59), while all other assessed variables were not. Patients undergoing PSMA PET imaging were more likely to undergo targeted radiation therapy, while no differences were seen in rates of hormonal therapy utilization.
Based on these results, the study investigators concluded as follows:
- The imaging modality was not predictive of salvage therapy utilization; however, PSMA PET imaging was associated with increased uptake of targeted radiation therapy.
- While salvage therapy was initiated earlier at lower PSA levels and appears more targeted in the PSMA PET group, no benefit has yet been demonstrated for subsequent recurrence rates. Longer term follow-up is needed to further evaluate this.
Presented by: Lufan Wang, MSc, Department of Epidemiology & Biostatistics, University of California, San Francisco, CA
Written by: Rashid K. Sayyid, MD, MSc – Robotic Urologic Oncology Fellow at The University of Southern California, @rksayyid on Twitter during the 2025 Genitourinary (GU) American Society of Clinical Oncology (ASCO) Annual Meeting, San Francisco, CA, Thurs, Feb 13 – Sat, Feb 15, 2025.