Metastatic prostate cancer proven by 18F-FCH PET/CT staging scan in patient with normal PSA but high PSA doubling time.

A 59-year-old man presented with frequent urination. Six months ago, his prostate-specific antigen (PSA) was 1.56 ng/mL; currently it is 3.5 ng/mL (PSA doubling time = 6 months; PSA velocity = 0.19 ng/mL/mo). Biopsy revealed aggressive prostate cancer (Gleason score 5 + 5). Staging with (18)F-fluorocholine PET/CT ((18)F-FCH PET/CT) demonstrated lymph node metastasis. After 6 months of hormonal therapy with goserelin, PSA decreased to 0.38 ng/mL. A (18)F-FCH PET/CT restaging scan demonstrated a global reduction of (18)F-FCH lesion uptake with disappearance of some mediastinal and iliac pelvic lymph node activity.