Predictive factors of [18F]-Choline PET/CT in 170 patients with increasing PSA after primary radical treatment
Menée sur 170 patients atteints d'un cancer de la prostate traité par résection radicale, cette étude évalue, du point de vue de la sensibilité et de la spécificité, l'intérêt d'une tomographie numérique par émission de positrons à base de choline (18F) dans la restadification de la maladie chez les patients présentant après traitement une élévation du niveau sérique de l'antigène prostatique spécifique
Aim : The purpose of this study was to evaluate the potential usefulness of [18F]-Choline PET/CT in the restaging of prostate cancer patients, who presented a rising PSA.
Materials and methods : We evaluated 170 prostate cancer patients, previously radically treated, that were referred for restaging with [18F]-Choline PET/CT.
Results : A total of 129 patients (median PSA 4.29 ng/ml at relapse) showed one or more areas of high uptake on PET/CT scan, while 41 patients with a median PSA of 1.07 ng/ml at relapse showed negative PET/CT scans. No false negative was found, while 31 patients were identified as false positive. Specificity of Choline PET/CT in our series was 56.9 %, while sensibility was 100 %. At the time of restaging, a PSA value superior or equal to 1 ng/ml was found to be a statistically significant predictive factor of PET positivity, either at the univariate (p < 0.0001) and at the multivariate analysis (p < 0.0001).
Conclusions : Based on our findings, [18F]-Choline PET/CT is confirmed as a useful diagnostic tool to detect early recurrence, in patients with increasing PSA after primary treatment. However, in case of a mild increase in PSA, positive results must be validated with other techniques, as specificity and positive predictive value of [18F]-Choline PET/CT decrease with the lower values of PSA.
Journal of Cancer Research and Clinical Oncology , résumé, 2013