Combined 18F-fluorocholine and 18F-fluoride positron emission tomography/computed tomography imaging for staging of high-risk prostate cancer

Objective: To investigate how often positron emission tomography/computed tomography (PET/CT) scans, with both (18)F-fluorocholine and (18)F-fluoride as markers, add clinically relevant information for patients with prostate cancer who have high-risk tumours and a normal or inconclusive planar bone scan.

Patients and methods: Patients with prostate cancer with prostate specific antigen (PSA) levels between 20 and 99 ng/mL and/or Gleason score 8-10 tumours, planned for treatment with curative intent based on routine staging with a negative or inconclusive bone scan, were further investigated with a (18)F-fluorocholine and a (18)F-fluoride PET/CT. None of the patients received hormonal therapy before the staging procedures were completed.

Results: For 50 of the 90 included patients (56%) one or both PET/CT scans indicated metastases. (18)F-fluorocholine PET/CT indicated lymph node metastases and/or bone metastases in 35 patients (39%). (18)F-fluoride PET/CT was suggestive for bone metastases in 37 patients (41%). In 18 patients (20%) the PET/CT scans indicated widespread metastases, leading to a change in therapy intent from curative to non-curative. Of the patients with positive scans, 74% had Gleason score 8-10 tumours. Of the patients with Gleason score 8-10 tumours, 64% had positive scans.

Conclusions: PET/CT scans with (18)F-fluorocholine and (18)F-fluoride commonly detect metastases in patients with high-risk prostate cancer and a negative or inconclusive bone scan. For 20% of the patients the results of the PET/CT scans changed the treatment plan.