ETD

• [18F]FECH PET/CT
• f-MRI
• prostate cancer
• PSA

In prostate cancer patients with biochemical recurrence, distinguishing between local and distant failure is crucial to choose the most suitable treatment. In this study we assessed if the combination of f-MRI and [18F]FECH PET/CT could serve to optimize treatment decision making in patients with recurrent PCa after curative first-line treatment.
We enrolled 30 patients (mean age 72±7 yr) with biochemical relapse of PCa presenting about 6 yr after radical prostatectomy underwent consecutive DWI/DCE-MRI and [18F]FECH PET/CT dynamic PET imaging of the pelvic region + whole-body images, for a total of 60 studies. Each exam was classified as: indeterminate, negative or positive. Positive scans were further classified as positive for local relapse (candidate for standard salvage EBRT), oligo-metastatic (≤5 total lesions, candidate for EBRT) and pluri-metastatic disease (>5 total lesions, candidate for hormonal therapy, ADT).
The combination of DWI/DCE-MRI and [18F]FECH PET/CT detected disease recurrence in 27/30 patients: local relapse in 7, oligometastatic in 18 and plurimetastatic in 2. MRI was clearly superior in detecting local recurrence.On the other hand, [18F]FECH PET/CT detected more tumor lesions in case of metastatic disease. The combination of these two imaging modalities allowed in our patients an accurate definition of treatment planning, avoiding unnecessary systemic therapies.