HDR brachytherapy and radiotherapy as salvage treatment for macroscopic recurrence in the prostate bed after radical prostatectomy.

370 Background: To present early and late toxicity, biochemical, local, regional and distant control and survival in a prospective series of 75 patients with macroscopic local recurrence in the prostate bed after radical prostatectomy treated by salvage HDR brachytherapy. Methods: Between 12/1999 and 12/2020, 75 patients (pts) with exclusive macroscopic recurrence in the prostate bed after radical prostatectomy without nodal or distant metastases, were included in the study. Pts were prospectively treated by 46 Gy IMRT radiotherapy to the surgical bed followed by 16 Gy HDR brachytherapy in 2 implants of 8Gy each, one week apart and hormone therapy for 36 months. Rectal limitant dose was 85% and for urethra 115% of the prescribed dose. Toxicity was recorded according to the EORTC/RTOG criteria. Special attention to PSA levels, biochemical, local, nodal and distant metastases control and survival, as well as to quality of life was taken. Results: All pts completed treatment. No pts experienced grade 3 or higher rectal or urinary toxicity. odos los pacientes completaron el tratamiento. 2 pts presented G1 rectal toxicity (ocasional rectorragia) and 1 pts G2 rectitis (persistent rectorragia), that ceased with topic treatment (cortisone ointment) 1 Pts had G1 urethral toxicity (dysuria), that spontaneously disappeared qat few months no requiring any medical intervention. No patient developed stenosis, necrosis or urethral fistula during follow-up. With a median follow-up of 102 months, 13 pts had failure of the disease: 6 biochemical-only, 2 local recurrence, 2 pelvic recurrence, 1 paraaortic recurrence and 2 distant metastases. 2 patients died by the disease and 1 patient died by other cause (age related). Conclusions: IMRT plus HDR brachytherapy was a safe treatment without any early or late significant side-effect. Combined treatment by IMRT and HDR plus androgen deprivation was extraordinary effective in the control or macroscopic local recurrences in the prostatectomy bed after radical prostatectomy. Further studies are warranted.