PSMA staging is linked with higher rates of ADT, ARPI utilization in prostate cancer

Higher rates of androgen deprivation therapy (ADT) and androgen receptor pathway inhibitor (ARPI) utilization were observed in patients undergoing prostate-specific membrane antigen (PSMA) staging vs conventional imaging, according to results of an emulated randomized trial presented at the 2025 American Society of Clinical Oncology Genitourinary Cancers Symposium in San Francisco, California.¹

Sean R. Miller, MD

“There has been rapid uptake of PSMA PET staging since FDA approval in 2020, with 70% of unfavorable intermediate risk or higher patients undergoing PSMA PET in the Veteran’s Health Administration (VHA) in June 2023,”² wrote the authors, led by Sean R. Miller, MD, of the department of radiation oncology at the Veteran Affairs Ann Arbor Healthcare System and department of radiation oncology at the University of Michigan, Ann Arbor. The investigators added that 8.2%, 14%, and 34% of unfavorable intermediate-risk (UIR), high-risk (HR), and very high-risk (VHR) were upstaged by PSMA PET respectively to either N1 M1 disease.²

“The impact of staging with PSMA PET on treatment decisions is not known,” they added in their poster.

For their study, the investigators evaluated men with newly diagnosed prostate cancer at the VHA that was UIR, HR, or VHR as indicated by Gleason Score, tumor stage, and prostate-specific antigen level, proven by biopsy, who had no radiographic evidence of N+ or M+, and had not received PSMA or bone scan prior to biopsy.

The primary outcome use of ADT within 1 year following diagnosis, and secondary outcomes included use of an ARPI, radiotherapy, and radical prostatectomy. Emulated random assignment was used to place patients in conventional imaging or PSMA PET arms.

The investigators identified 20,458 patients with newly diagnosed prostate cancer in the VHA between January 1, 2022 and December 21, 2023. Patients with pelvic imaging prior to enrollment who exhibited evidence of nodal or distant metastasis, had received bone scan or PSMA PET/CU prior to enrollment, had started prostate cancer treatment prior to enrollment, had incorrect follow-up date, or who had low- or favorable intermediate-risk disease were excluded, leaving a population of 9049 patients, of whom 3199 underwent PSMA staging, 4130 underwent bone scan, and 1720 underwent neither a PSMA staging nor bone scan.

Regarding patient characteristics, median patient age was 70 or 71 years across the groups undergoing PSMA, bone scan, or neither PSMA or bone scan. National Comprehensive Cancer Network (NCCN) risk group was UIR in 1104 (35%) patients in the PSMA group, 1646 (40%) patients in the bone scan group, and 1081 (63%) patients in the neither PSMA nor bone scan group. NCCN risk group was HR in 1393 (44%) patients in the PSMA group, 1672 (40%) patients in the bone scan group, and 441 (26%) patients in the neither PSMA nor bone scan group. NCCN risk group was VHR in 702 (22%) patients in the PSMA group, 812 (20%) patients in the bone scan group, and 198 (12%) patients in the neither PSMA nor bone scan group.

“PSMA staging was associated with higher rates of any ADT usage relative to conventional staging,” the investigators reported in their abstract. The adjusted HR (aHR) was 1.26 (95% CI, 1.19-1.44). An association between PSMA staging and higher ARPI use was also observed (aHR: 1.52; 95% CI, 1.33-1.78), as was an association between PSMA staging and lower prostatectomy usage (aHR: 0.69; 95% CI, 0.56-0.83). PSMA staging did not appear to have a significant impact on radiation therapy utilization, according to the investigators.

“PSMA PET staging resulted in intensification of systemic therapy and de-intensified local surgical therapy,” the investigators wrote in their conclusion.

REFERENCES

1. Miller SR, Gonzalez RT, Jackson WC, et al. Impact of PSMA PET staging on initial treatment in newly diagnosed prostate cancer: An emulated randomized controlled trial. J Clin Oncol 43, 2025 (suppl 5; abstr 350). doi:10.1200/JCO.2025.43.5_suppl.350

2. Miller SR, Gonzalez RT, Jackson WC, et al. Rates of PSMA PET staging and positivity in newly diagnosed prostate cancer in a national health care system. J Nucl Med. 2025;66(1):75-83. doi:10.2967/jnumed.124.268555