The following is a summary of “Impact of 18F-fluciclovine PET/CT on plans for androgen deprivation therapy in patients with biochemical recurrence of prostate cancer: data analysis from two prospective clinical trials,” published in the June 2023 issue of the Urologic Oncology by Andriole et al.
Despite advances in early detection and primary therapy, biochemical recurrence (BCR) of prostate cancer is still prevalent. The advent of highly sensitive molecular imaging has facilitated the identification of men with limited metastatic disease burden who may benefit more from metastases-directed therapy than androgen deprivation therapy (ADT). The LOCATE (NCT02680041) and FALCON (NCT02578940) trials evaluated the impact of 18F-fluciclovine PET/CT on managing patients with BCR after primary therapy with curative intent. Researchers performed a secondary analysis of LOCATE and FALCON data to characterize recurrence sites and management decisions for BCR patients with an intended management plan that included ADT before 18F-fluciclovine PET/CT.
Analyzing data from 317 LOCATE/FALCON patients who underwent 18F-fluciclovine PET/CT, those with a prescan intention for ADT (± another treatment) were selected. At the patient level, 18F-Fluciclovine detection rates were determined for the prostate/prostate bed region, pelvic and extra-pelvic lymph nodes (LN), soft tissues, and bones. The pre- and post-scan patient treatment regimens were compared and stratified based on imaging results. About 146 patients (60 as monotherapy and 86 in combination with another modality) had a prescan regimen for ADT. 85 of 146 (58%) planned ADT patients were found to have lesions by 18F-Fluciclovine. Around 30%, 25%, 13%, 2.1%, and 13% were the detection rates in the prostate/bed, pelvic LN, extra-pelvic LN, soft tissues, and bone.
About 25 patients (17%) had positivity limited to the prostate/bed, 21 patients (14%) had 18F-fluciclovine-positive pelvic LN (prostate/bed) but no other involvement, and 39 patients (27%) had involvement outside of the prostate/bed and pelvic LN. Post-scan, 93 of 146 (64%) patients had a change in management, with 55 (59%) being to discontinue ADT. Post-scan, only 25% of the patients initially slated for ADT monotherapy maintained their original plan. The most disseminated disease was observed in patients with a post-scan ADT monotherapy regimen. Those whose plans to discontinue ADT were changed had the highest incidence of prostate/bed disease. 18F-Fluciclovine-PET/CT influenced the preponderance of ADT prescan patients’ treatment strategies. Commonly, plans were modified to target salvage therapy for lesions identified with 18F-fluciclovine PET/CT, which likely spared/delayed patients from ADT-related morbidity.
Source: sciencedirect.com/science/article/pii/S1078143923001205
