Praful Ravi, MB, BChir, MRCP, on PSMA-PET during initial systemic therapy for mHSPC

In the following video, conducted at the 2026 American Society of Clinical Oncology Annual Meeting, Praful Ravi, MB, BChir, MRCP, discusses results from PSMAtrack, which assessed the role of PSMA-PET imaging in evaluating early treatment response in patients with metastatic hormone-sensitive prostate cancer (mHSPC).¹ Ravi is a genitourinary medical oncologist at the Dana-Farber Cancer Institute in Boston, Massachusetts.

According to Ravi, the study was motivated by 2 established clinical insights: that PSMA-PET is commonly used at diagnosis for staging but rarely tracked during therapy, and that prostate-specific antigen (PSA) level at 6 months into treatment is strongly prognostic, with a PSA below 0.2 ng/mL predicting favorable long-term outcomes and a PSA above 0.2 ng/mL associated with significantly worse survival. Ravi and his team sought to combine these 2 threads by examining how PSMA-PET findings at baseline and 6 months correlate with PSA response.

The pilot study enrolled 20 patients with mHSPC confirmed on conventional imaging, all of whom underwent F18-flotufolastat PSMA-PET at baseline and again after 6 months of ADT plus an androgen receptor pathway inhibitor, with or without docetaxel.

The investigators found that all 20 patients (100%) had residual PSMA-avid disease at 6 months, and 85% had residual disease outside of the prostate. When the cohort was stratified by PSA response, important quantitative differences emerged between the 2 groups. Patients achieving a PSA less than 0.2 ng/mL (n = 9) had a median total tumor volume (TTV) of 7.7 mL and a median SUVmax of 8.7, while those with a PSA of 0.2 ng/mL or greater (n = 11) had a dramatically higher median TTV of 147 mL and a median SUVmax of 47.4 (difference between groups, P < .01 for both).

Beyond the primary end point, the study demonstrated strong correlations between PSA and PSMA-PET–derived TTV at both baseline (r=0.68; P = .001) and at 6 months (r = 0.81; P <.01, as well as between changes in each measure over the treatment period (r=0.67; P = .001). Baseline TTV also correlated strongly with 6-month PSA (r=0.74; P < .01), suggesting that pre-treatment PSMA-PET burden may help predict which patients will have a suboptimal early response. According to the authors, these findings support the potential use of 6-month PSMA PET as a tool to identify patients with mHSPC for consolidative therapy after suboptimal initial response to standard therapy.

REFERENCE

1. Ravi P, Shah H, Liu M, et al. Quantitative results from PSMAtrack: A prospective study evaluating changes in PSMA-PET during initial systemic therapy for metastatic hormone-sensitive prostate cancer (mHSPC). J Clin Oncol. 2026 (suppl 16; abstr 5102). doi:10.1200/JCO.2026.44.16_suppl.5102