Role of PET-CT with 18F-fluorocholine in biochemical recurrence after treatment of prostate cancer with curative intent

Objectives: To analyse the ability of the PET-CT with F-18-fluorocholine (F-18-FCH) to detect disease on biochemical recurrence after treatment with curative intent. To determine the clinical variables that would be able to optimise the test's diagnostic yield. Material and methods: A retrospective study of PET-CTs with F-18-fluorocholine performed on 61 patients with prostate cancer who had undergone treatment with curative intent and met the criteria for biochemical recurrence. The results of the PET-CT were categorised into positive or negative and were validated using pre-established criteria. The relationship between the result of the PET-CT and the initial PSA nadir, PSA trigger, rising PSA velocity (PSAva) and PSA doubling time (PSAdt). The relationship between the metastatic sites on the PET-CT and the remaining variables was analysed. Results: There was a 34.4% detection rate of the disease. The initial PSA, PSA nadir, PSA trigger and PSAva showed statistically significant differences according to the result of the PET-CT. The best discriminatory cut-off point between a positive or negative PET-CT for PSA trigger and PSAva was 3.5 ng/ml and 0.25 ng/ml/month respectively. The PSAdt was significantly lower in patients with remote disease compared to patients with localised disease (5.1 vs 16.8 months, P=.01). The probability that the PET-CT would detect remote disease vs localised disease was 3.2 times higher if the PSAdt was under 6 months (80% vs 20%, OR: 3.2, P=.02). In the multivariate analysis, only the initial PSA and not having undergone radical prostatectomy were demonstrated as independent predictive factors of a positive PET-CT result. Conclusions: The PET-CT with F-18-FCH can detect disease in a high percentage of patients with biochemical recurrence and provides information on its anatomical location. PSA kinetics and the patient's previous treatment are key variables in increasing the test's diagnostic. (C) 2017 AEU. Published by Elsevier Espana, S.L.U. All rights reserved.