PSMA PET/CT Impacts the Clinical Management Plans of Patients With Prostate Cancer and BCR

The US Food and Drug Administration (FDA) approved the use of prostate-specific membrane antigen positron emission tomography (PSMA PET) scans for the evaluation of patients with prostate cancer in 2021. Following that approval, the clinical management plans of 39% to 62% of patients with prostate cancer outside of the United States have been impacted by the use of PSMA PET.

Within the United States, the impact of PSMA PET on care management has not been thoroughly examined. To gain more insight, a team of researchers based in Massachusetts and Texas carried out a study on the routine clinical use of PSMA PET, its impact on the management of biochemical recurrence (BCR), and its relationship to other clinical parameters.

The study analyzed 91 patients with prostate cancer and BCR who had received ⁶⁸Ga-PSMA and ¹⁸F-piflufolastat PET/computed tomography (CT) between October 2021 and March 2022. Patient management plans, prostate-specific antigen (PSA) levels, and Gleason scores were compared. Imaging reports were reviewed for locations of PSMA-avid lesions.

The care management plans for 53 patients (58%, group 1) were changed after those patients underwent PSMA PET/CT, while 38 patients (42%, group 2) did not experience a change in their management plans. PSA levels and Gleason scores were higher in group 1 than group 2, although not significantly (PSA level: 8.02±29.9 vs 3.29±5.2 ng/mL; P=.4; Gleason ≥8: 19/29 [69%] vs Gleason <8: 33/62 [53%]; P=.15).

The detection of previously known PSMA-avid osseous lesions was associated with management changes (P=.01), but the detection of lesions in other anatomic locations was not. PSMA PET/CT findings resulted in more intensified treatment. In 3 patients, treatment plans were changed from chemoradiation to PSA surveillance as no localizable disease was detected on PSMA PET/CT (n=2). A subset of patients scheduled for hormone therapy was switched to active surveillance after those patients received negative PSMA PET scans.

A total of 36 patients with an initial management plan of PSA surveillance had their management plans updated to other procedures, including prostate bed and/or pelvic lymph node radiotherapy, chemotherapy and hormone therapy either combined or as a monotherapy, and radiotherapy plus chemotherapy or hormone therapy. A total of 17 patients with an initial management plan of prostate bed radiotherapy, chemotherapy, or hormone therapy received PSA surveillance instead.

Following FDA approval, the routine use of PSMA PET/CT has had a noticeable impact on the clinical management of patients with prostate cancer and BCR. Patients who had no PSMA-avid lesions or newly identified osseous lesions were impacted the most.