Long-Term Outcomes of Whole Gland Salvage Cryotherapy for Locally Recurrent Prostate Cancer following Radiation Therapy: A Combined Analysis of Two Centers.

PURPOSE: Radiation refractory prostate cancer (RRPCa) is common and salvage cryotherapy for RRPCa is emerging as a viable local treatment option. However, there is a paucity of long-term data. The purpose of this study is to determine long-term outcomes following salvage cryotherapy for RRPca. MATERIALS AND METHODS: Patients undergoing salvage cryotherapy for biopsy-proven, localized RRPCa from 1992 through 2004 were prospectively accrued at two centers. Preoperative characteristics, perioperative morbidity and postoperative data were reviewed from our database. The primary outcomes were overall survival (OS) and disease-specific survival (DSS). The secondary outcomes were freedom from castration-resistant prostate cancer (CRPC) and freedom from androgen deprivation therapy (ADT). RESULTS: A total of 268 patients were identified with a median followup of 10.3 years. A total of 223 complication events were recorded; of them, 168 were Clavien I-II events and 55 Clavien III events. At 10 years, 69% had freedom from ADT and 76% had freedom from CRPC. The 10-year DSS rate was 81%, and the 10-year OS rate was 77%. A pre-salvage prostate specific antigen level of >10 ng/ml was associated with an increased risk of developing CRPC and initiation of ADT but was not associated with DSS or OS. The use of neoadjuvant ADT was associated with improved OS and DSS but did not affect freedom from CRPC or adjuvant ADT. CONCLUSIONS: Salvage cryotherapy for RRPCa provides excellent long-term freedom from ADT, CRPC and DSS with acceptable morbidity. OS at 10 years was 77%. Prospective trials are required for validation.

Comparison of salvage radical prostatectomy vs. salvage ablation therapy for biopsy-proven radio-recurrent localized prostate cancer.

INTRODUCTION: Radiation therapy for prostate cancer is associated with a 15-20% five-year recurrence rate. Patients with recurrence in the prostate only are candidates for salvage local therapies; however, there is no consensus on modality. This study uses registries at Memorial Sloan Kettering Cancer Center (MSKCC) and University of Western Ontario (UWO) to compare the oncologic outcomes of salvage radical prostatectomy (SRP) and salvage ablation (SA). METHODS: A total of 444 patients were available for analysis. Due to intergroup differences, propensity score methodology was used and identified 378 patients with more comparable pre-salvage prostate-specific antigen (PSA), Gleason score, and primary radiation treatment. Patients underwent SRP at MSKCC and SA at UWO. RESULTS: Of the 378 patients, 48 died of disease, with a 6.0-year median (interquartile range [IQR] 3.0, 9.7) followup among survivors; 88 developed metastases, with a median 4.6-year (IQR 2.3, 7.9) followup among metastasis-free survivors. There was a non-significantly higher rate of cancer-specific (hazard ratio [HR ] 1.02, 95% confidence interval [CI] 0.51, 2.06, p=0.9) and improved metastasis-free survival (HR 0.71, 95% CI 0.44, 1.13, p=0.15) among patients undergoing SA compared to patients undergoing SRP. There were 143 patients who received hormonal therapy, with higher rates of androgen deprivation therapy (ADT) in SA (HR 1.42, 95% CI 0.97, 2.08, p=0.068), although this did not meet conventional levels of significance. CONCLUSIONS: This propensity score analysis of salvage therapy for radio-recurrent prostate cancer identified no statistically significant differences in oncologic outcome between SRP and SA; however, there was evidence of a lower risk of ADT in the cohort undergoing SRP. Given they are both potentially curative therapies, these treatments are viable options for men with clinically localized, radio-recurrent prostate cancer rather than ADT alone. Future research may further elucidate subpopulations that may be more amenable to either SRP or SA.

Salvage open radical prostatectomy for recurrent prostate cancer following MRI-guided transurethral ultrasound ablation (TULSA) of the prostate: feasibility and efficacy.

Introduction: MRI-guided transurethral ultrasound ablation (TULSA) is a novel modality for minimally invasive ablation in patients with localised prostate cancer (PCa). A multi-national Phase 1 (30 patients) and subsequent Phase 2 (115 patients) study showed TULSA to be feasible, safe and well tolerated. However, technical viability and safety of salvage prostatectomy for those who failed TULSA is unclear. Herein, we report the feasibility and morbidity of salvage radical prostatectomy (sRP) post-TULSA.Methods: Four patients with biopsy-proven residual cancer following TULSA underwent open retropubic sRP within 39 months of TULSA. Peri-and post-operative morbidity were reported. Detailed histopathologic assessment is reported.Results: Median follow-up was 43 months after sRP. Mean operating times, blood loss, and length of stay were 210 min, 866 ml, and 3.5 days, respectively. Intraoperative finding of some fibrotic reaction of endopelvic and Denonvilliers fascia was characteristic. There were no perioperative complications. Whole-mount pathology sections showed one pT2b and three pT3a, suggesting under-staging pre-TULSA. Location of disease was compatible with persistent cancer mostly in the untreated peripheral safety region. One man received an artificial urinary sphincter. All men experienced erectile dysfunction responsive to treatment. Two patients with positive surgical margins had PSA progression requiring salvage radiation, with one requiring long-term androgen deprivation therapy.Conclusions: RP is a viable and safe salvage option if TULSA fails. Technical difficulty and perioperative morbidity were negligible and attributable to minimal peri-prostatic reaction from TULSA.

Abiraterone acetate preferentially enriches for the gut commensal Akkermansia muciniphila in castrate-resistant prostate cancer patients.

Abiraterone acetate (AA) is an inhibitor of androgen biosynthesis, though this cannot fully explain its efficacy against androgen-independent prostate cancer. Here, we demonstrate that androgen deprivation therapy depletes androgen-utilizing Corynebacterium spp. in prostate cancer patients and that oral AA further enriches for the health-associated commensal, Akkermansia muciniphila. Functional inferencing elucidates a coinciding increase in bacterial biosynthesis of vitamin K2 (an inhibitor of androgen dependent and independent tumor growth). These results are highly reproducible in a host-free gut model, excluding the possibility of immune involvement. Further investigation reveals that AA is metabolized by bacteria in vitro and that breakdown components selectively impact growth. We conclude that A. muciniphila is a key regulator of AA-mediated restructuring of microbial communities, and that this species may affect treatment response in castrate-resistant cohorts. Ongoing initiatives aimed at modulating the colonic microbiota of cancer patients may consider targeted delivery of poorly absorbed selective bacterial growth agents.