Salvage HDR brachytherapy for prostate cancer: a high-volume center experience on 100 consecutive patients

AIM: This study aims to evaluate the safety and efficacy of salvage HDR brachytherapy in patients who have undergone a thorough diagnostic process. MATERIALS AND METHODS: 100 prostate cancer patients - locally relapsed after previous radiotherapy - were treated with salvage HDR brachytherapy to a total dose of 24 Gy. Before treatment, the patients underwent PET imaging, prostate MRI, and prostate biopsies to confirm local relapse and exclude systemic disease. Concomitant ADT was applied in 69 patients. Toxicity and efficacy data were collected as a patient chart review. Toxicity was graded using Common Terminology Criteria for Adverse Events (CTCAE 5.0). RESULTS: The 3-year bDFS and OS were 74% (confidence interval [CI] 95%: 60-87%) and 93% (CI 95%: 84-100%), respectively. Acute Grade 1-2 genitourinary toxicity was observed in 70 patients, 58 patients with Grade 1 and 12 patients with Grade 2, respectively. Acute Grade 1 gastrointestinal toxicity was observed in 8 patients. CONCLUSIONS: This retrospective study shows that salvage HDR brachytherapy is a well-tolerated and effective treatment for histologically proven, local radio-recurrent disease.