Session Item

The purpose of our study is to evaluate, in patients with macroscopic local relapse after radical prostatectomy, the efficacy of salvage radiotherapy on the prostatic bed with a boost to the area of the recurrence on CSS (cancer specific survival), PFS (progression free survival) and OS (overall survival).

This study includes 17 patients (median age 67 years, range 52-75 years), with macroscopic local recurrence treated between 2014 and 2019 with radiotherapy on the surgical bed and sequential stereotactic (SBRT) boost +/- hormonal deprivation therapy (ADT). A macroscopic local recurrence was defined by a relapse in prostatic bed evidenced with choline PET and confirmed with multi-parametric MRI. The total dose applied to the prostate bed was 60 Gy in 30 fractions. Sequential boost dose was 16 Gy in 4 SBRT fractions. Three patients (17.6%) received also ADT.

After a median follow-up of 70 months (range 32-90 months), 14 patients were alive and 3 died (1 for disease and 2 for causes not related with prostatic disease). The 5-year overall survival (OS) rate was 86.5%. The 5-year progression free survival (PFS) rate was 82.4%. Biochemical progression occurred in two patients (11.8%) and were treated with ADT. One patient (5.9%) developed single bone metastasis and one patient (5.9%) had lymph-node progression. No local recurrence was observed. The 5-year cancer specific survival (CSS) rate was 92.3%. The median of OS, PFS and CSS were not reached. No high grade (≥ 3) toxicity was reported. 

Although limited, our experience showed that sequential SBRT boost in patients with macroscopic local relapse after radical prostatectomy was well tolerated and ensure a high rate of local control, OS, PFS and CSS.