Salvage cryosurgery for locally recurrent prostate cancer after primary 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.

The Role of Whole-Gland and Focal Cryotherapy in Recurrent Prostate Cancer

Prostate cancer is the most common non-cutaneous malignancy in men, with the majority of newly diagnosed patients eligible for active surveillance. Despite definitive treatment, a considerable percentage of men will experience biochemical recurrence and even regional and distant metastatic recurrence after radiation therapy or radical prostatectomy. Salvage prostatectomy, while oncologically effective, poses significant morbidity with poor functional outcomes. Salvage cryotherapy has emerged as a promising alternative for localized recurrence, demonstrating safety and efficacy. This review examines the oncologic and functional outcomes of whole-gland and focal salvage cryotherapy, including disease-free survival, cancer-specific survival, and overall survival. The crucial role of multiparametric prostate MRI and evolving role of next-generation PSMA-targeted PET imaging are also examined. The comparison of outcomes of cryotherapy to other salvage ablation modalities, such as high-intensity focused ultrasound (HIFU), is also explored.

Salvage treatments after focal therapy for prostate cancer - a comprehensive review

OBJECTIVE

To review the literature on salvage treatments after focal therapy (FT) for prostate cancer (PCa).

MATERIALS AND METHODS

A non-systematic literature review was conducted on PubMed, Scopus, and Web of Science up to March 15, 2024, for studies that assessed salvage treatment outcomes in patients with recurrent PCa after primary FT. Original prospective and retrospective studies with more than 10 patients were included. Reviews, editorial comments, conference abstracts, and studies focusing solely on whole-gland treatments were excluded.

RESULTS

Twenty-one studies with a total of 1012 patients were included. The most reported salvage treatments were salvage radical prostatectomy followed by re-do ablation therapy. Only one study evaluated salvage radiation therapy. Except for one prospective study, all studies were retrospective. Oncological outcomes showed acceptable biochemical recurrence rates. Functional outcomes varied, with significant impacts observed on erectile function across modalities, though continence rates were less impacted. Complications were generally low across all treatment options.

CONCLUSION

Salvage treatment post-primary FT is feasible, safe, and has reasonable oncologic outcomes. However, significant declines in sexual function are common, while continence is comparatively less affected. The literature primarily consists of retrospective studies; hence, future research should focus on large-scale prospective evaluations to better define treatment protocols and improve patient outcomes.

Salvage Cryoablation for Recurrent Prostate Cancer Following Primary External Beam Radiotherapy or Primary Cryotherapy: A Propensity Score Matched Analysis of Mid-term Oncologic and Functional Outcomes

INTRODUCTION

Local prostate cancer recurrence following radiotherapy (XRT) or cryoablation (CRYO) may be addressed with salvage cryotherapy (SCT), although little is known about how the primary treatment modality affects SCT results. Oncologic and functional outcomes of patients who underwent SCT after primary XRT (XRT-SCT) or cryoablation (CRYO-SCT) were studied.

METHODS

Data was collected using the Duke Prostate Cancer database and the Cryo On-Line Data (COLD) registry. The primary outcome was biochemical progression-free survival (BPFS).  Urinary incontinence, rectourethral fistula, and erectile dysfunction were secondary outcomes. The Kaplan-Meier log-rank test and univariable/multivariable Cox proportional hazards (CPH) models were utilized to evaluate BPFS between groups.

RESULTS

419 XRT-SCT and 63 CRYO-SCT patients met inclusion criteria, that was reduced to 63 patients in each cohort after propensity matching. There was no difference in BPFS at 2 and 5 years both before (P = .5 and P = .7) and after matching (P = .6 and P = .3). On multivariable CPH, BPFS was comparable between treatment groups (CRYO-SCT, HR=1.1, [0.2-2.2]).  On the same analysis, BPFS was lower in D'Amico high-risk (HR 3.2, P < .01) and intermediate-risk (HR 1.95, P < .05) categories compared to low-risk. There was no significant difference in functional outcomes between cohorts.

CONCLUSION

Following primary cryotherapy, salvage cryoablation provides comparable intermediate oncological outcomes and functional outcomes compared to primary radiotherapy.

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 partial gland ablation for recurrent prostate cancer following primary partial gland ablation: Functional and oncological outcomes

INTRODUCTION AND OBJECTIVE

Partial gland ablation (PGA) for localised prostate cancer (CaP) aims to eradicate clinically significant tumours while preserving healthy tissue, thereby decreasing the likelihood of side effects compared to whole-gland approaches. Although salvage radical prostatectomy (sRP) is a well-described salvage option in cases of PGA failure, the evidence supporting salvage PGA (sPGA) is limited. We hereby report the oncologic and functional outcomes of patients treated with sPGA following initial treatment with primary PGA (pPGA).

METHODS

We describe the findings of a retrospective review of patients who had a CaP recurrence after pPGA and then underwent sPGA, at 3 medical centers in Ontario, Canada, between 2005 and 2017. Oncological outcomes following sPGA were assessed for biochemical recurrence (BCR) and biopsy-proven recurrence (BPR). Functional outcomes were described using the international prostate symptom score (IPSS), international index of erectile function (IIEF), and rates of urinary incontinence (use of >1 pad/day).

RESULTS

We identified 25 patients who underwent sPGA following pPGA (hemiablation in 48% and zonal ablation in 52% of the patients). The median length of time was 16.8 months (interquartile range [IQR] 14.0-19.1) from pPGA to sPGA and 47.06 months (IQR 19.9-171.3) from pPGA to date of last follow up. High intensity focused ultrasound (HIFU) was the only modality used in all patients. At baseline, the median age was 65 years (IQR 52-77) and median prostate specific antigen (PSA) level was 7.46 ng/mL (IQR 1-25). The median time from pPGA to BPR was 12.7 months (IQR 5.19-36). At BPR following pPGA, 4 patients (17%) had CaP grade group (GG) 1, 10 patients (42%) had GG2, 6 patients (25%) had GG3, and 4 patients (17%) had GG4 disease, with a median PSA of 3.58 ng/mL (IQR 0.67-19). The median length of follow up after sPGA was 27.3 months (IQR 14.5-86.3). Following sPGA, 13/25 patients (52%) had BCR with median time to recurrence of 14 months (IQR 2.5-82.15), with a recurrence-free survival of 24.5 months (95% confidence interval: 15.3-not reached). Of those 13 patients, 4 were managed with sRP, 4 were managed with salvage radiotherapy, 3 were managed with androgen-deprivation therapy, 1 had a third PGA with HIFU, and 1 was managed with active surveillance. The mean change from baseline to last follow up in IPSS and IIEF scores was +1.3 (P = 0.66) and -2.3 (P = 0.32), respectively. Urinary incontinence was reported by 9% of patients at baseline, with only one additional patient developing incontinence following sPGA.

CONCLUSION

Our present study demonstrates that after a median follow-up of 27 months, sPGA for recurrent CaP following pPGA provides disease control in up to 50% of patients with nonsignificant detrimental effects on functional outcomes. Appropriate patient selection and adequate staging are important to consider before offering PGA to patients.

Analysis of Several Pathways for Efficient Killing of Prostate Cancer Stem Cells: A Central Role of NF-κB RELA

Prostate cancer is a common cause of death worldwide. Here, we isolated cancer stem cells (CSCs) from four adenocarcinomas of the prostate (Gleason scores from 3 + 3 up to 4 + 5). CSCs were characterized by the expression of the stem cell markers TWIST, the epithelial cell adhesion molecule (EPCAM), the transcription factors SNAI1 (SNAIL) and SNAI2 (SLUG) and cancer markers such as CD44 and prominin-1 (CD133). All investigated CSC populations contained a fraction highly positive for aldehyde dehydrogenase (ALDH) function and displayed robust expressions of programmed cell death 1 (PD-1) ligands. Furthermore, we investigated immunotherapeutic approaches but had no success even with the clinically used PD-1 inhibitor pembrolizumab. In addition, we studied another death-inducing pathway via interferon gamma signaling and detected high-level upregulations of human leukocyte antigen A (HLA-A) and beta 2-microglobulin (B2M) with only moderate killing efficacy. To examine further killing mechanisms in prostate cancer stem cells (PCSCs), we analyzed NF-κB signaling. Surprisingly, two patient-specific populations of PCSCs were found: one with canonical NF-κB signaling and another one with blunted NF-κB activation, which can be efficiently killed by tumor necrosis factor (TNF). Thus, culturing of PCSCs and analysis of respective NF-κB induction potency after surgery might be a powerful tool for optimizing patient-specific treatment options, such as the use of TNF-inducing chemotherapeutics and/or NF-κB inhibitors.

Translation of Cryobiological Techniques to Socially Economically Deprived Populations—Part 2: Cryosurgery

Cold and cryogenic temperatures are used for treating cancer and other pathological conditions in various fields of medicine. Cryosurgery, which resides at the interface of medicine and engineering, has attracted the interest of engineers, scientists, and medical doctors. Recently, particularly since the end of the 1980s, technological developments in cryotherapy equipment and enormous advances in imaging techniques, such as computed tomography and ultrasonography, have allowed surgeons and interventional radiologists to precisely guide cryogenic probes into tumors while avoiding damage to surrounding tissues. Extensive studies have allowed us to conclude that the use of cryogenics facilitates the successful treatment of solid tumors in various organs such as lung, liver, bones, kidneys, prostate, etc. Its simplicity of use, effectiveness, low cost, and limited demand on hospital infrastructure and personnel have made cryosurgery particularly suitable for the treatment of patients of socio-economically deprived populations.

Cryosurgery would be An Effective Option for Clinically Localized Prostate Cancer: A Meta-analysis and Systematic Review

Cryosurgery (CS) has been used on patients with clinically localized PCa for more than 10 years. However, clinical studies evaluating its effectiveness and safety have reported conflicting results. This systematic assessment was performed to obtain comprehensive evidence regarding the potential benefits and safety of CS compared with those of radiotherapy (RT) and radical prostatectomy (RP), respectively. All controlled trials comparing CS with RT or RP and single-arm studies reporting results of CS therapy were identified through comprehensive searches of PubMed, the Cochrane Library and Embase. Ten publications from seven trials, with totally 1252 patients, were included in the meta-analysis, which revealed no significant differences in comparisons of CS vs RT and CS vs RP for overall survival and disease specific survival. However, a significantly lower disease-free survival could be observed for CS than RP. Moreover, a systematic review of literature focusing on comparative data of databases and materials of single-arm trials revealed satisfactory survival results in both primary and salvage CS. Our results showed that cryosurgery would be a relatively effective method for clinically localized prostate cancer with survival results comparable to radiotherapy and radical prostatectomy. However, the large percentage of complications caused by cryosurgery should be carefully monitored.

The feasibility and safety of repeat cryosurgical ablation of localized prostate cancer

BACKGROUND

The aim of the study was to assess the morbidity and efficacy of repeat cryoablation (CA) in the treatment of localized prostate cancer.

METHODS

Twenty-seven patients with median age of 71 years (range 48-80) who underwent repeat CA between April 2003 and April 2011 at a single institution were included. The median initial prostate-specific antigens (PSA) and Gleason values were 6.2 ng/ml (range 4-23.6) and 7 (range 6-9), respectively. Twenty-four patients underwent two CA treatments, and three patients underwent three CA treatments. Pre- and perioperative parameters and oncological and functional outcomes were evaluated.

RESULTS

No intraoperative complications occurred. After the first CA, PSA was undetectable in 10 patients, and the median nadir PSA value was 0.65 ng/ml (range 0.1-4.9). After the second CA, 4 patients had undetectable PSA, and the median nadir PSA value was 1.25 ng/ml (range 0.2-7.9). For patients who underwent a third CA treatment, no patients had undetectable PSA, and the subsequent median nadir PSA value was 1.6 ng/ml (range 0.4-4.5). Two patients had incontinence (1 pad per day) following repeat CA. One patient had urinary retention after the third CA treatment, and one had urethral stricture. The mean hospitalization and follow-up periods were 1 day (range 0-2) and 51.5 months (range 11-96), respectively.

CONCLUSIONS

Repeat CA successfully reduced PSA levels, and complications were modest. We conclude that repeat CA is a feasible, safe, and effective treatment option for localized prostate cancer.