How many patients could have a salvage local treatment after radiotherapy/brachytherapy for prostate cancer?

Abstract

23 Background: In our institution, as soon as biochemical relapse (BR; nadir PSA + 2 ng/ml) occurred after external beam radiotherapy (EBRT) or brachytherapy (BT), 18-fluorocholine-PET-CT (18-FCH-PET) with or without multiparametric prostate MRI are performed. The aim is to select patients for a salvage local treatment (SLT) with a curative intent. We presented here the results of this approach. Methods: Records of patients with BR, without clinical evidence of relapsing disease and with at least a18-FCH-PET performed, were retrospectively reviewed. Patients were considered eligible for SLT if the relapse was only local or in case of nodal relapse reasonably encompass in a RT field. Results: Between 2010 and 2014, 89 pts were included, 23 initially treated with BT and 66 with EBRT. Prognostic group at diagnosis were: favourable: 25 (28%), intermediate: 35 (39%), unfavourable: 29 (33%). At the time of relapse, mean age was 72 yrs and mean PSA level: 6.2 ng/ml. After 18-FCH-PET ± MRI, patients were classified as: no target lesion identified: 20 (22.5%); local relapse: 35 (39%); nodal relapse: 22 (25%); distant metastases: 12 (13%.5%). Among 35 pts with a local relapse, 14 had SLT (cryotherapy:13; cyberknife:1). Reasons to not performed SLT were: advanced age or poor performance status: 10; Gleason 8-10: 2; T3 on MRI: 2; Patient refusal (fear of incontinence): 7. Among 22 pts with a nodal relapse, only 3 could have salvage EBRT. Reasons to not performed SLT were: old age or poor PS: 5; extensive nodal relapse: 8; local and nodal relapse: 6. At the end, 57 pts (64%) are potentially eligible for SLT and 17 (19%) could have it. Conclusions: In routine practice, in a population of 89 pts with a BR, 64% are eligible for SLT but 19% could have it. Main reasons for not having SLT were absence of target lesions, extensive disease, or advanced age. This result justified the realisation of an extensive staging at the time of BR after EBRT or brachytherapy.