Oncological outcomes of 356 patients undergoing salvage focal ablative HIFU or cryotherapy following radiation failure.

Abstract

5582 Background: Patients that have previously failed radiotherapy for prostate cancer is usually limited to systemic therapy due to morbidity from salvage prostatectomy. We reviewed the outcomes following focal salvage ablative therapy with HIFU or cryotherapy within the UK’s HEAT and ICE registries. Methods: 356 consecutive patients underwent focal ablative treatment after initial radiation treatment failure (28/1/2004-1/10/2019, 194 (54.5%) underwent HIFU (posterior recurrence) and 162 (45.5%) underwent cryotherapy (mostly anterior or T3b). Primary outcome was failure-free survival (FFS) defined as no systemic therapy, whole-gland treatment, metastases or prostate cancer-specific death. Secondary outcomes were adverse events and overall survival. Results: Median (IQR) age was 69years (65-73) and PSA (IQR) was 4.0ng/ml (1-7-7.2). Overall median (IQR) follow-up was 41.3 months (21.4-58.5). Quadrant ablation was performed in 128 (36.0%), hemi-ablation performed in 64 (18.0%), hockey-stick in 5 (1.4%) and 159 (43.8%) had unknown ablative patterns. Due to histological or MRI proven recurrence/residual disease, 31 (8.7%) underwent further focal salvage re-treatment. FFS (95%CI) at 3 and 6 years were 81% (76-87%) and 75% (68-83%) respectively. Median (IQR) time to failure was 15.5 months (19.7). Overall survival (95%CI) at 3 and 6 years were 97% (95-100%) and 88% (81-96%) respectively. Prostate-specific mortality was 2.8%. Overall 3 (0.8%) patients were managed for fistula formation, 16 (4.5%) were treated for UTIs. Conclusions: Salvage focal ablative therapy for radio-recurrent prostate cancer is safe and provides good short to medium-term oncological control. The FORECAST study is awaited to further determine oncological outcomes in this cohort.