Effects of Focal vs Total Cryotherapy and Minimum Tumor Temperature on Patient-reported Quality of Life Compared With Active Surveillance in Patients With Prostate Cancer

Focal cryotherapy for prostate cancer: a contemporary literature review

Objective

To perform a comprehensive review of the contemporary literature regarding both functional and oncologic outcomes after primary focal cryotherapy for prostate cancer (PCa), providing these results as a foundation for discussing recent developments in the realm of focal therapy.

Background

Traditional treatments for PCa are often associated with debilitating functional side effects for patients. Due to advances in imaging and biopsy strategies, focal ablative therapies recently have garnered much interest and offer an alternative primary treatment for PCa patients with localized disease. Focal cryoablation utilizes heat extraction from tissues to generate an iceball and cause tissue destruction while sparing uninvolved prostatic regions. Optimized patient selection and postoperative management continue to be areas of interest and study as the field continues to develop.

Methods

A search was performed of the PubMed and Embase databases to identify articles pertaining to primary focal PCa cryoablation since our group's last comprehensive review in 2016.

Conclusions

Primary focal cryoablation for PCa offers optimized functional outcomes and a favorable adverse event profile. True evaluation of oncologic outcomes is hampered by lack of long-term follow-up and highly variable clinical endpoints across these studies. Nonetheless, outcomes appear adequate in the short- to medium-term time frame. Utilization of focal cryoablation is expected to grow with continued refinement of patient selection and management options in cases of treatment failure.

Effect of Prostate Volume and Minimum Tumor Temperature on 4-Year Quality-of-Life After Focal Cryoablation Compared with Active Surveillance in Men with Prostate Cancer

Background: The purpose of this study is to analyze quality-of-life (QoL) metrics in men treated with focal cryoablation (FC) compared with active surveillance (AS) for localized prostate cancer over a 4-year follow-up period. We further investigated the effect of prostate size and minimum tumor temperature on QoL outcomes. Methods: An Institutional Review Board-approved database was reviewed for patients who underwent FC or AS. QoL questionnaire responses were collected and scores were analyzed for differences between FC and AS, between prostate volume <50 cc and ≥50 cc, and "cold" (<-78°C) and "warm" (≥-78°C) tumor temperatures. Results: One hundred forty-eight AS and 60 FC patients were included. Compared with AS, no significant difference existed in urinary function (UF) measured by Expanded Prostate Cancer Index Composite (EPIC) (p = 0.593) and International Prostate Symptom Score (IPSS) (p = 0.241), bowel habits (p = 0.370), or anxiety (p = 0.672) across time post-FC. FC had significantly worse sexual function (SF) compared with AS measured by EPIC (p < 0.0001) and International Index of Erectile Function (IIEF) (p < 0.0001). Patients with prostate volume <50 cc did not demonstrate differences between AS and FC in UF on EPIC (p = 0.459) or IPSS (p = 0.628), but FC patients had worse SF on EPIC (p < 0.001) and IIEF (p < 0.001). FC patients with a prostate volume ≥50 cc had better UF measured by IPSS (p < 0.05) and similar SF on EPIC (p = 0.162) and IIEF (p = 0.771) compared with AS. UF over time measured by EPIC (0.825) and IPSS (p = 0.658) was the same between AS, "warm," and "cold" FC groups. AS had significantly better SF than the "warm" and "cold" FC groups on EPIC (p < 0.001) and IIEF (p < 0.05). Conclusions: No differences were found in anxiety, urinary, or bowel function between AS and FC. Despite differences in SF, patients with larger prostates had no difference in SF and improved UF compared with AS. Future studies with larger cohorts are needed.

Focal therapy of localized prostate cancer

In the treatment of localized prostate cancer, controlling the cancer and maintaining quality of life are important. Focal therapy of localized prostate cancer aims to treat the lesion/part of the prostate that includes the index lesion, which determines the prognosis. We performed a non-systematic review of novel studies on focal therapy of localized prostate cancer as primary treatment published between 2016 and 2021. For mainly intermediate-risk patients, therapeutic technology, such as cryoablation, brachytherapy, high-intensity focused ultrasound, photodynamic therapy, microwave-coagulation, electroporation, and laser ablation, etc., were performed. These procedures are minimally invasive and safe, and provide good functional outcome: a 94-100% pad-free rate against urinary incontinence and 47-86% erectile function, which is sufficient for sexual intercourse. Accurate three-dimensional mapping of the targeted lesion could be an essential navigation technique for therapeutic success. Intermediate- to short-term oncological outcomes were good, resulting in downstaging of the patient's status to no clinically significant cancer; however, transition to conventional whole-gland treatment was necessary in about 10-30% of patients. It is important to select appropriate patients by both multiparametric magnetic resonance imaging and targeted biopsy, and to follow-up postoperatively with methods such as active surveillance. Clinically significant prostate-specific antigen reduction, image response using preoperative and postoperative multiparametric magnetic resonance imaging, and histological analysis should be combined for follow-up.

Comparative results of focal-cryoablation and stereotactic body radiotherapy in the treatment of unilateral, low-to-intermediate-risk prostate cancer

OBJECTIVE

The purpose of this study is to compare oncologic and functional outcomes of men with unilateral, localized PCa treated with stereotactic body radiotherapy (SBRT) versus focal cryoablation (FC).

METHODS

Patients from our IRB-approved PCa database who underwent FC or SBRT and were eligible for both treatments were included. Patients with less than 1 year of follow-up or prior PCa treatment were excluded. The primary outcome was treatment failure, defined as salvage treatment or a Gleason group (GG) of ≥ 2 on post-treatment biopsy. Biochemical recurrence (BCR) was evaluated with Phoenix. Functional outcomes were based on EPIC surveys. Complications were categorized with the CTCAE 5.0. Outcomes were compared using descriptive statistics, univariate analyses, and Kaplan-Meier curve for failure-free survival (FFS) and BCR-free survival. P < 0.05 was significant.

RESULTS

68 FC and 51 SBRT patients with a median age of 68 years (48-86) and a median follow-up time of 84 (70-101) months were included in this analysis. There was no difference in tumor risk (p = 0.47), GG (p = 0.20), or PSA (p = 0.70) among the two cohorts at baseline. At 7-year follow-up, no difference in FFS was found between the two cohorts (p = 0.70); however, significantly more FC patients had BCR (p < 0.001). At 48 months, no differences existed in urinary or bowel function; however, SBRT patients had significantly worse sexual function (p = 0.032).

CONCLUSION

FC and SBRT are associated with similar oncologic and functional outcomes 7-year post-treatment. These results underscore the utility of FC and SBRT for the management of unilateral low-to-intermediate-risk PCa.

Detailing Sexual Outcomes After Focal Therapy for Localised Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

Focal therapy has emerged as a promising option to treat well-selected men with localised prostate cancer while preserving healthy prostate tissue and key structures, such as the urethral sphincter and neurovascular bundles. However, how this tissue preservation may translate into improved outcomes, particularly into improved sexual outcomes, is still an active research field.

OBJECTIVE

We conducted a systematic review and meta-analysis of the literature to summarise the existing evidence, in order to provide patients with updated data on what to expect after treatment and help identify gaps in current knowledge that may warrant future research.

EVIDENCE ACQUISITION

A systematic literature search was conducted on Medline, EMBASE, Scopus, and Web of Science. The search strategy was defined using the "litsearchr" function in R based on a preliminary "naïve" search using the following terms on Medline: (("focal therapy" OR "focal treatment") AND ("prostate cancer") AND ("sexual function" OR "erectile function")). A total of 42 studies, comprising 3117 patients treated and 2352 with available sexual outcomes, were included in the qualitative data synthesis and 26 in a random-effect meta-analysis.

EVIDENCE SYNTHESIS

The five-item International Index of Erectile Function (IIEF-5) was the most frequently used questionnaire (30/42 studies), with completion rates ranging from 24% to 100% at 18-24 mo. A decrease was noted at 3 mo (IIEF-5 decrease estimate -3.70 [95% confidence interval -4.43, -2.96]), with improvements at 6 mo (-2.18 [-2.91, -1.46]) and 12 mo (-2.14 [-2.96, -1.32]). Studies in which patients had an altered baseline sexual function were more likely to report a significant and durable postoperative decrease in erectile function scores. The patient-reported outcome questionnaires used were not designed for a diverse population. Functional outcomes were not the primary endpoint and have not been reported consistently in most studies considered.

CONCLUSIONS

Focal therapy led to changes in erectile function in most cases under the significance threshold of the patient-reported outcome questionnaires used. However, patients should be counselled according to their baseline erectile function. More research is warranted to detail aspects other than erectile function, such as ejaculation or orgasm. The early postoperative period appears key to study sexual changes after focal therapy, while only a moderate decrease is expected at 12 mo.

PATIENT SUMMARY

We reviewed the published literature detailing the sexual consequences of focal therapy for localised prostate cancer using patient-reported outcome questionnaires. Patients were likely to describe a significant decrease in their erectile function at 3 mo, with improvements noted at 6 and 12 mo. The results obtained may not be reproducible in a more diverse population, and further research is warranted to better study aspects other than erectile function, such as ejaculation or orgasm.

An Updated Systematic Review on Focal Therapy in Localized Prostate Cancer: What Has Changed over the Past 5 Years?

CONTEXT

Focal therapy is a promising, minimally invasive strategy to selectively treat localized prostate cancer. A previous systematic review indicated that there is growing evidence for favorable functional outcomes, but that oncological effectiveness was yet to be defined.

OBJECTIVE

To assess the effectiveness of focal therapy in patients with localized prostate cancer in terms of functional and oncological outcomes.

EVIDENCE ACQUISITION

PubMed, Embase, and The Cochrane Library were searched for studies between October 2015 and December 31, 2020. In addition, the research stages were acquired according to the Idea, Development, Exploration, Assessment, Long-term study (IDEAL) recommendations. Ongoing studies were identified through clinical trial registries.

EVIDENCE SYNTHESIS

Seventy-two studies were identified exploring eight different sources of energy to deliver focal therapy in 5827 patients. Twenty-seven studies reported on high-intensity focused ultrasound (HIFU), nine studies on irreversible electroporation, 11 on cryoablation, eight on focal laser ablation and focal brachytherapy, seven on photodynamic therapy (PDT), two on radiofrequency ablation, and one on prostatic artery embolization. The majority of studies were prospective development stage 2a studies (n = 35). PDT and HIFU, both in stage 3, showed promising results. Overall, HIFU studies reported a median of 95% pad-free patients and a median of 85% patients with no clinically significant cancer (CSC) in the treated area. For PDT, no changes in continence were reported and a median of 90% of patients were without CSC. Both treatments were well tolerated.

CONCLUSIONS

Over the past 5 yr, focal therapy has been studied for eight different energy sources, mostly in single-arm stage 2 studies. Although a first randomized controlled trial in focal therapy has been performed, more high-quality evaluations are needed, preferably via multicenter randomized controlled trials with long-term follow-up and predefined assessment of oncological and functional outcomes and health-related quality-of-life measures.

PATIENT SUMMARY

Focal treatment (FT) of prostate cancer has potential, considering that it has less impact on continence and potency than radical treatment. Our systematic review indicates that despite the method being studied extensively over the past half decade, the majority of studies remain in an early research stage. The techniques high-intensity focused ultrasound and photodynamic therapy have shown most progression toward advanced research stages and show favorable results. However, more high-quality evidence is required before FT can become available as a standard treatment.

Current evidence for focal therapy and partial gland ablation for organ-confined prostate cancer: systematic review of literature published in the last 2 years

PURPOSE OF REVIEW

The shift in the diagnostic algorithm for prostate cancer to early imaging with mpMRI has resulted in many patients being diagnosed with small volume, apparently unilateral, clinically significant cancers. In these patients, a minimally invasive, nonmorbid intervention is appealing. The aim of this study was to review data reported within the last 2 years on focal therapy and partial gland ablation for organ-confined prostate cancer.

RECENT FINDINGS

High-intensity focal ultrasound, focal cryotherapy, photodynamic therapy, irreversible electroporation and focal laser ablation, have been used as treatment modalities for localized prostate cancer treatment. The reported oncologic outcomes vary widely and makes comparisons challenging. All the focal therapies report low rates of complications, and high rates of continence and erectile function preservation. The most common adverse events are hematuria, urinary retention and urinary tract infections. During this period, the initial results of several new technologies including MRI-guided transurethral ultrasound ablation were published.

SUMMARY

Focal therapy and partial gland ablation for organ-confined prostate cancer is an option for patients with intermediate-risk disease because of its low complication profile and preservation of QOL. Trials comparing the outcome of different focal therapy technologies have not been carried out, and the existing evidence does not point to one approach being clearly superior to others. Long-term oncologic outcome is lacking. Despite this, for men with unilateral intermediate-risk prostate cancer whose disease is often relatively indolent, focal therapy is an appealing option.

Primary cryotherapy for localized prostate cancer treatment

INTRODUCTION

Prostate cryotherapy is an available treatment option for localized prostate cancer (PC) included on minimal invasive therapies but still under evaluation. We started our cryotherapy program in 2008 for selected patients with localized PC. Our objective is to evaluate the oncologic and functional outcomes of primary cryotherapy in men with clinically localized PC.

SUBJECTS AND METHODS

We retrospectively evaluated all patients who underwent primary cryotherapy for localized PC treatment at our center between January 2008 and December 2017. In order to downsize prostates between 40 and 60cc neoadjuvant 3-month hormonal therapy was administered. Primary endpoint was biochemical progression-free survival (BPFS) rate as defined by the Phoenix criteria. Secondary endpoints were cancer-specific survival (CSS), overall survival (OS), patient reported functional outcomes and complication rates. Factors influencing de BPFS were evaluated individually using Kaplan-Meyer and Cox regression models and in a multivariate model using Cox regression.

RESULTS

During the mentioned period, a total of 177 men were treated with cryotherapy. With a mean follow-up of 60 months (SD 32.9), the Kaplan-Meier analysis shows an overall BPFS rate was 67%. BPFS by risk group was 70.2%, 70.3% and 50.0% for the low, intermediate and high risk groups, respectively (p = 0.925). Overall time to BR was 93.67 months (SD 2.84, IC95%: 88.10-99.24): 95.91 (SD 3,44), 93.23 (SD 4.81) and 89.77 (SD 6.67) months for the low, intermediate and high risk groups, respectively. In both univariate and multivariate analysis, the only predictor of biochemical progression was de PSA nadir (HR 1.56 IC95%: 1.50-1.63). Continence was fully maintained in 95% of patients after the procedure. Postoperative complications included UTI (17.5%), hematuria (9.6%), perineal hematoma (11%) and postoperative pain (4.5%). No fistulas were reported. 8.5% of patients had acute urinary retention solved conservatively.

CONCLUSION

Cryotherapy is a safe option for selected patients with localized prostate cancer that provides competitive oncologic outcomes and a low morbidity profile.

Contemporary treatments in prostate cancer focal therapy

PURPOSE OF REVIEW

Radical treatments for prostate cancer are associated with significant morbidity, including incontinence and erectile dysfunction. Advances in the field of prostate MRI and desire to reduce treatment morbidities have led to a rapid growth in focal treatments for prostate cancer. Here, we review novel focal prostate cancer treatments and their associated recent clinical data, with a particular focus on data reported within the last 24 months.

RECENT FINDINGS

High-intensity focal ultrasound, focal laser ablation, irreversible electroporation, focal cryotherapy, and photodynamic therapy have been used as treatment modalities for localized prostate cancer treatment. Despite the great variety of treatment techniques, each of these modalities is characterized by a significant rate of prostate cancer persistence within treatment zones (6-50%) and the presence of residual cancer within the prostate on rebiopsy (24-49%). These treatments, however, are associated with very low rates of high-grade complications, rare incontinence, and only mild or transient reductions in erectile function. The most common adverse events are urinary tract infections, hematuria, and urinary retention.

SUMMARY

Prostate cancer focal therapy is an attractive option for well-selected patients because of its low complication profile; however, long-term oncologic outcome is still lacking and early recurrence rates are high, limiting the ability of most urologic associations from endorsing its routine use.

Quality of life worsened the most severely in patients immediately after intensity-modulated radiotherapy for prostate cancer

Purpose

The aim of this study was to evaluate the chronological changes in lower urinary tract symptoms (LUTSs), disease-related quality of life (QOL), and health-related QOL (HR-QOL) of patients who received intensity-modulated radiotherapy (IMRT).

Patients and methods

In 121 patients who had received IMRT and were followed up for >2 years, the International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS), Expanded Prostate Cancer Index Composite (EPIC), and 8-Item Short-Form Health Survey (SF-8) were used before IMRT, at the halfway point in IMRT, immediately after IMRT, and 1–24 months after the completion of IMRT.

Results

The IPSS and OABSS and the urinary and bowel domains of the EPIC indicated that QOL worsened at the halfway point in IMRT, further worsened more severely immediately after IMRT, and then improved. The sexual domain of the EPIC significantly decreased at the halfway point in IMRT, which significantly lowered until 24 months. The scores of physical functioning, role physical, bodily pain, vitality, social functioning, and role emotional domains in the SF-8 significantly decreased and reached their lowest points immediately after IMRT.

Conclusion

QOL worsened the most severely in patients immediately after IMRT for prostate cancer. This knowledge can influence treatment recommendations and enable patients to make better informed decisions.