Brachytherapy for the treatment of recurrent prostate cancer after radiotherapy or radical prostatectomy

Abstract

What's known on the subject? and What does the study add? The curative treatment of prostate cancer includes surgery, external beam radiation or interstitial radiation. However, a high percentage of patients may develop recurrent disease, which is often localised. The possibilities of treatment in these cases, including surgery or adjuvant radiotherapy, are not well defined. Brachytherapy is a well established first-line treatment option. We review and update the use of brachytherapy in the treatment of recurrences post-radiotherapy, brachytherapy or radical prostatectomy as an alternative to surgery and radiotherapy, with a focus on functional and oncological outcomes. Salvage therapeutic options following radical prostatectomy or radiotherapy for patients with local relapse of prostate cancer include radical prostatectomy, radiotherapy, brachytherapy or cryotherapy. Salvage radical prostatectomy following radiotherapy failure is associated with a 5-year PSA relapse-free rate of 30-40%. Biochemical relapse-free survival rates after salvage radiotherapy following radical prostatectomy failure range from 10% to 77% after a follow-up of 22-60 months. A number of studies have evaluated salvage brachytherapy for radiotherapy failure and 5-year biochemical disease-free survival (bDFS) rate results reported are of the order of 20-87%; one study reported a 10-year bDFS rate of 54%. Fewer studies in small numbers of patients and with shorter follow-up have been conducted on brachytherapy for radical prostatectomy failure and bDFS rates reported include 25.8% at a median of 29 months to 70% at a median of 20 months. The side-effects were as expected for brachytherapy. A newer initiative conducted in Spain in a larger series of 42 patients with failure following radical prostatectomy involves brachytherapy with RAPID Strand™(125) I seeds and real-time placement. The 5-year bDFS rate was 88.6% and cancer-specific survival was 97%; complication rates were low. Optimization of salvage brachytherapy is under way and involves accurate placement of seeds, dose optimization and optimal patient selection.