Salvage Ablation for Locally Recurrent Prostate Cancer

Derek J. Lomas; David A. Woodrum; Lance A. Mynderse

Disclosures

Curr Opin Urol. 2021;31(3):188-193. 

In This Article

Oncologic Outcomes

Reporting of oncologic outcomes varied by study, but the most common metric used was BCR as defined by the Phoenix definition.[10–14] Two recent meta-analyses have reported on salvage local therapies after radiation.[3,15] Ingrosso et al. included 22 salvage cryotherapy studies in their review.[15] Biochemical control was reported in 10 of the included studies with a pooled-prevalence of 60% with follow-up ranging from 15 to 63 months. Valle et al. included 32 studies that evaluated salvage cryotherapy.[3] Two- and five-year recurrence-free survival rates were 68 and 50%, respectively.

Several recent studies have also reported on oncologic outcomes of salvage whole gland salvage cryotherapy (Table 1). Bain et al. reported on long-term follow-up of 37 cryotherapy patients.[10] Biochemical recurrence occurred in 57% with a median time to BCR of 18 months. At 2 years, BCR-free rate was 71%. Metastatic progression occurred in seven patients (19%) during follow-up. Nair et al. reported on 187 patients who underwent salvage cryotherapy with a 10-year Kaplan–Meier estimated BCR rate of 55.8%.[13] The 10-year estimates of metastasis and cancer-specific mortality rates were 21.2% and 15.8%, respectively. The same group also found that cancer-specific survival and overall survival were superior with cryotherapy compared to no salvage treatment.[16] Safavy et al. retrospectively reviewed 75 patients that underwent salvage cryotherapy.[14] Most patients underwent whole gland treatment (93.3%). BCR-free survival was 50.7% at a median of 3.9 years. Metastasis developed in 10 (13.3%) patients. In another retrospective review of 169 patients, the 5- and 8-year BCR-free survival rates were 52% and 45%, respectively.[12] Nair et al. compared salvage cryotherapy to salvage prostatectomy.[17] Ten-year BCR-free survival favored prostatectomy at 44.8% compared to 31.9% with cryotherapy. Conversely, metastasis-free survival was 83% with cryotherapy compared to 73% with prostatectomy. There were no significant differences in cancer-specific survival or overall survival at 10 years.

Avoidance of ADT is also a motive for pursuing salvage therapy. Bauman et al. conducted a propensity-matched analysis of salvage cryotherapy vs. ADT for local recurrence after radiation.[18] Cryotherapy was associated with longer overall survival (12.3 vs. 10.2 years). Ten-year prostate cancer-specific mortalities were similar between the cryotherapy and ADT groups, 16.2 and 18.5%, respectively. Most cryotherapy patients did eventually require ADT with 90% starting by 20 years with a mean time to ADT of 11 years. In other studies, ADT initiation ranged from 30% at 5 years to 51% at 10 years.[12,13]

Due to morbidity associated with whole gland ablation, focal or partial gland ablation has been of considerable interest. A recent systematic review reported on seven studies that evaluated focal salvage cryotherapy.[19] Five-year biochemical disease-free survival ranged from 46.5 to 54.4% in the included studies and rates of metastasis were 10–21.3%. Bomers et al. reported on 62 patients that underwent salvage MRI-guided focal cryotherapy with follow-up >12 months.[11] Biochemical disease-free survival after 12 months was 63% based on Kaplan–Meier analysis. Biopsy of the edge of the ablation zone was negative in 77% of patients at 12 months. At 12 months, the metastatic disease had been identified in 10 patients, local recurrence in 10, and BCR in 2.

Several studies identified predictive factors associated with salvage cryotherapy success. Multiple studies reported that higher presalvage PSA was a significant predictor of adverse outcomes.[13,14,17] Low PSA nadir after cryotherapy was a predictor of success in two studies.[12,14] Other predictors of success included lower presalvage cryotherapy Gleason score and longer time to PSA nadir after radiotherapy[14] as well as PSA level at initial diagnosis, age at salvage, and a shorter interval between primary treatment and salvage cryotherapy.[12]

processing....