Randomized Trial of Prostate-Specific Membrane Antigen PET/CT Before Definitive Radiotherapy for Unfavorable Intermediate- and High-Risk Prostate Cancer (PSMA-dRT Trial).

This multicenter randomized phase III trial (NCT04457245) evaluated the effect of performing prostate-specific membrane antigen (PSMA) PET/CT before definitive radiotherapy. Methods: Men with unfavorable intermediate- or high-risk prostate cancer were randomized 1. 08:1 between receiving and not receiving a PSMA PET/CT scan before definitive radiotherapy. All other imaging modalities were allowed in the control arm. The primary endpoint was 5-y progression-free survival. Results: Fifty-four men were randomized between November 2020 and December 2021 (PSMA PET/CT, n = 25; control, n = 29). The trial closed early after approval and insurance coverage of PSMA PET/CT. In the PSMA PET/CT arm, 14 patients had localized disease (miT2b-cN0M0), 6 had locally advanced disease (miT3a-bN0M0), 3 had regional metastasis (miN1M0), and 1 had distant metastasis (miM1b). Four patients were upstaged. Conclusion: PSMA PET/CT upstaged 17% of patients, which allowed for more accurate radiotherapy planning. Unfortunately, this trial closed early before completion of target enrollment (54/316, 17%) and was underpowered to assess the effect of PSMA PET/CT on progression-free survival.

Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2024 Apr 25 [Epub ahead of print]

John Nikitas, Ethan Lam, Kiara Adame Booker, Wolfgang P Fendler, Matthias Eiber, Boris Hadaschik, Ken Herrmann, Nader Hirmas, Helena Lanzafame, Martin Stuschke, Johannes Czernin, Michael L Steinberg, Nicholas G Nickols, Amar U Kishan, Jeremie Calais

Department of Radiation Oncology, UCLA, Los Angeles, California., Ahmanson Translational Theranostics Division, Department of Molecular and Medical Pharmacology, UCLA, Los Angeles, California., Department of Nuclear Medicine, University of Duisburg-Essen and German Cancer Consortium-University Hospital Essen, Essen, Germany., Department of Urology, University of Duisburg-Essen and German Cancer Consortium-University Hospital Essen, Essen, Germany., Department of Radiotherapy, University Hospital Essen, University of Duisburg-Essen, Essen, Germany; and., Ahmanson Translational Theranostics Division, Department of Molecular and Medical Pharmacology, UCLA, Los Angeles, California; .