Salvage Intensity-Modulated Radiation Therapy for Locally Recurrent Prostate Cancer After Cryotherapy

Salvage local treatment for recurrent prostate cancer after focal therapy: A systematic review and meta-analysis

OBJECTIVES

To evaluate the role of salvage local treatment in managing recurrent PCa following FT, focusing on oncological and functional outcomes.

METHODS

A systematic review and meta-analysis were performed following the PRISMA framework. A comprehensive literature search using the PubMed/MEDLINE and EMBASE databases was performed until July 2023. Eligible studies included patients with clinically localised PCa initially treated with FT, who experienced relapse during surveillance and subsequently underwent salvage radical prostatectomy (sRP), salvage external beam radiation therapy (sEBRT) or salvage focal therapy (sFT). The primary endpoint was the biochemical recurrence rate post-salvage treatment. The secondary endpoints were functional outcomes, including urinary incontinence and erectile dysfunction rates.

RESULTS

In 26 retrospective studies including 990 patients, the overall pooled biochemical recurrence rate postsalvage treatment was 26%. The subgroup analysis revealed a biochemical recurrence rate of 20%, 22%, and 42% after sRP, sEBRT, and sFT, respectively. The overall pooled rate of urinary incontinence was 20%. Salvage FT had the lowest prevalence of urinary incontinence, followed by sRP and sEBRT. The overall pooled rate of erectile dysfunction was 43%. Salvage RP had the highest prevalence of erectile dysfunction, followed by sFT and sEBRT. Substantial heterogeneity was observed among the studies, primarily due to different sample sizes. Meta-regression analysis revealed no to low contributions of salvage treatment modalities, extent of ablation, age, prostatic specific antigen level before salvage treatment, proportion of patients with Gleason score ≥7 at recurrence, and time between the primary and salvage therapies to heterogeneity.

CONCLUSION

Salvage local treatment for recurrent PCa after FT is feasible, and it provides acceptable oncological and functional outcomes. Among all treatment modalities, sRP and sEBRT appeared to have the lowest biochemical recurrence rates, whereas sFT was associated with improved functional outcomes.

Salvage prostate intensity modulated radiation therapy after cryotherapy failure

Cryotherapy is an ablative therapy that can be used to treat localized prostate cancer. In case of recurrence, treatment options are not well-defined, and their outcomes are unknown. We therefore collected all patients treated with radiotherapy after cryotherapy for prostate cancer recurrence in Nantes (France) between 2012 and 2019. We identified ten patients. After a median follow-up of 5 years, two patients presented late grade 3 toxicities; one patient presented a grade 3 rectal hemorrhage, and one had a grade 3 hematuria. Two patients relapsed at 61 and 62 months, and three patients died of other causes. Radiotherapy to treat local prostate cancer recurrence after cryotherapy seems feasible and effective in local control. These results do not allow us to recommend this technique in current practice but are encouraging for the conduct of prospective trials.

Salvage radiotherapy after initial cryotherapy for localized prostate cancer: A systematic review of the literature

The treatment of local prostate cancer recurrence after cryotherapy is challenging since the optimal management is unknown. We collected the available evidence to date to better define the risk and benefit of salvage radiotherapy (SRT) after cryotherapy failure for localized prostate cancer. This review confirms the feasibility of SRT in terms of biochemical control and late toxicity rate. However, the absence of comparative trials or prospective studies, coupled with the heterogeneity of patients treated and the variations in treatments delivered across the analyzed studies, highlights the need for cautious consideration when opting for salvage radiotherapy. Therefore, we highly recommend the inclusion of patients in dedicated clinical trials to comprehensively assess the efficacy and safety of this approach.

Intermediate-term oncological and functional outcomes of salvage cryotherapy for the management of prostate cancer recurrence after primary brachytherapy versus primary cryotherapy: A propensity score-matched analysis

BACKGROUND

Salvage cryotherapy (SCT) is widely used to treat prostate cancer (PCa) recurrence after radiotherapy (RT). We studied the intermediate oncological and functional outcomes of patients who underwent SCT following cryotherapy (CRYO-SCT) recurrence and compare it to recurrence after brachytherapy (BT-SCT).

METHODS

An IRB-approved retrospective cohort study utilizing patient data from the Cryo On-Line Data Registry and the Duke PCa database between 1992 and 2016. Biochemical recurrence (BCR) using Phoenix criteria was the primary endpoint assessed at 2- and 5-years post-SCT. Secondary endpoints assessed functional outcomes including urinary continence, erectile function, and recto-urethral fistula. Association between treatment and biochemical progression-free survival was assessed using inverse probability weighted (IPTW) Cox proportional hazards regression. The differences in the secondary functional outcomes were assessed by Pearson's χ2 test or Fisher's exact test, corrected for IPTW.

RESULTS

A total of 194 patients met inclusion criteria. The BCR rate for BT-SCT and CRYO-SCT was 23 (20.4%) and 17 (21%) at 2 years and 30 (26.5%) and 22 (27.2%) at 5 years according to Phoenix criteria. There was no statistical difference in 2 years (hazard ratio [HR] 0.9; 95% confidence interval [CI], 0.5-1.7, p = 0.7) or 5-year BCR (HR: 0.86; 95% CI, 0.5-1.5, p = 0.6) between the groups. The functional outcomes like urinary continence (p = 0.4), erectile function (p = 0.1), and recto-urethral fistula (p = 0.3) were not statistically different.

CONCLUSION

CRYO-SCT appears to be well tolerated, with comparable oncological and functional outcomes to patients failing primary BT. The findings also demonstrated that SCT can render a significant number of patients biochemically free of disease after initial CRYO with minimal morbidity. SCT is a viable treatment option to salvage local PCa recurrence following either BT or cryoablation failure.

Salvage image guided radiation therapy to the prostate after cryotherapy failure

Purpose

Cryotherapy is an option for the primary treatment of localized prostate cancer, along with radical prostatectomy, external beam radiation therapy, and brachytherapy. Although it is known that local recurrence can occur in >20% of patients treated with primary cryotherapy, unfortunately there is a paucity of data on later salvage treatments. The use of external beam radiation therapy is an attractive option after cryotherapy failure, but there is little data on its efficacy and toxicity. We evaluated the biochemical control and complication rates of salvage dose-escalated image guided intensity modulated radiation therapy (IG-IMRT) after cryotherapy failure.

Methods and materials

Patients who were treated at our institution from 2005 to 2016 were reviewed for those who underwent cryotherapy as initial treatment followed by salvage IGRT. Patients were treated with dose-escalated IG-IMRT using standard treatment margins of 3 mm posterior and 7 mm in all other directions and daily cone beam computed tomography or kv imaging to implanted fiducial markers. Biochemical progression was defined in accordance with the Phoenix consensus conference definition.

Results

Eight patients were identified as having received post-cryotherapy salvage radiation within the study period. The median total dose was 77.7 Gy (range, 75.6-81.0 Gy). Median follow-up was 55 months (range, 6-88 months). Six patients remained biochemically controlled at the latest follow-up. One patient developed distant metastases after 22 months and one experienced biochemical failure at 30 months with no evidence of distant metastases. No patients experienced acute gastrointestinal toxicities of grade 2 or higher. There were no cases of late gastrointestinal or genitourinary toxicity.

Conclusions

High-dose IG-IMRT results in high rates of salvage and extremely low rates of serious late toxicity for patients with locally recurrent prostate cancer after cryotherapy. Although the results are encouraging, given the small number of patients in this and other series, we remain cautious with regard to this treatment and believe the use of salvage radiation therapy after cryotherapy warrants further study.

[Management of ablative therapies in prostate cancer]

OBJECTIVES

To describe the specific modalities of ablative therapies management in prostate cancer.

MATERIALS AND METHODS

A review of the scientific literature was performed in Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of keywords. Publications obtained were selected based on methodology, language and relevance. After selection, 61 articles were analysed.

RESULTS

Development of innovations such as ablative therapies in prostate cancer induces specific modalities in their management, during pre-, per- and post-procedure. More than for classical and well-known treatments, the decision to propose an ablative therapy requires analysis and consensus of medical staff and patient's agreement. Patient's specificities and economical aspects must also be considered. Procedures and follow-up must be realized by referents actors.

CONCLUSION

Indication, procedure and follow-up of ablative therapies in prostate cancer require specific modalities. They must be respected in order to optimize the results and to obtain a precise and objective evaluation for defining future indications.