New research was presented at ASTRO 2020, the virtual American Society for Radiation Oncology Annual Meeting, from October 24-28. 

The decision to offer radiation after prostatectomy for patients with recurrent prostate cancer shown to be complex and significant limitations of conventional imaging leave a need for more accurate radiation therapy decision making and treatment planning. Although the advanced PET radiotracer fluciclovine was approved in 2016 for use with PET imaging to help diagnose recurrence in men with treated prostate cancer and rising PSA levels, it is not currently used for radiation treatment planning. To shed light in this area, researchers randomized patients with recurrent prostate adenocarcinoma post-prostatectomy 1:1 to radiotherapy based on standard imaging (controls) or radiotherapy based on standard imaging plus fluciclovine PET/CT (PET-guided). Failure-free survival rates at 3 years were 75.5% for those in the PET-guided group, compared with 63.0% in the control group; respective rates at 4 years were 75.5% and 51.2%. Grade 3 genitourinary adverse events were experienced by no patients in the PET-guided group and 3.7% in controls. Acute gastrointestinal toxicities were not observed in either group.