Salvage cryoablation for locally recurrent prostate cancer following primary radiotherapy

摘要

Context: The purpose of this paper is to review current salvage cryoablation (SCA) outcomes in patients with locally recurrent prostate cancer (PCa) following primary radiation therapy. Objective: The objectives of this review are (1) to analyze the eligibility criteria for careful patient selection for these salvage modalities and (2) to evaluate the oncologic results and reported complication rates for these respective modalities. Evidence acquisition: A Medline/PubMed literature search was performed of peer-reviewed scientific articles published from 1991 to 2012 regarding salvage therapy for radiorecurrent PCa. The following search terms and various permutations were used: radiorecurrent prostate cancer, local salvage treatment, salvage radical prostatectomy, salvage cryoablation, salvage brachytherapy, and salvage high-intensity focused ultrasound. Only articles written in English were included. Evidence synthesis: SCA is a feasible and efficacious treatment modality, especially using third-generation technology, whereby the biochemical disease-free survival is estimated to be between 50% and 70% at 5-yr follow-up in properly selected patients. Severe complications such as rectourethral fistulas are significantly less common over the last decade than was reported in the past. Because there are no prospective, randomized studies and the definitions of PSA failure vary among many studies, comparisons between these different salvage modalities are limited in terms of cancer-specific outcomes. Nevertheless, in recent years, tertiary care referral centers for prostate cryotherapy have reported their treatment outcomes using rigorous treatment end points and morbidity grading systems, dramatically improving the quality of reported clinical data. Consequently, favorable predictors of treatment outcomes have been identified. Conclusions: The inability to effectively salvage patients with locally recurrent PCa following radiation therapy has in large part resulted from the lack of sufficiently sensitive and specific diagnostic tools to detect local recurrences at an early, potentially curable stage. Consequently, a more stringent definition of biochemical failure, improved imaging techniques, and accurate PCa mapping imaging technology is greatly needed within our diagnostic armamentarium. Additional research and randomized clinical trials are required to determine which salvage modality is superior in terms of oncologic efficacy and reduced morbidity.