Focal cryotherapy for clinically unilateral, low-intermediate risk prostate cancer in 73 men with a median follow-up of 3.7 years

Experimental study for in vitro prostate cancer treatment with microwave ablation and pulsed electromagnetic field

This paper presents the findings of a comprehensive study exploring the synergistic effects arising from the combination of microwave ablation and pulsed electromagnetic field (PEMF) therapy on prostate cancer cells. The research encompassed five distinct experimental groups, with continuous electric field measurements conducted during the entire treatment process. Group 1 and Group 2, subjected to microwave power below 350 W, exhibited specific electric field values of 72,800 V/m and 56,600 V/m, respectively. In contrast, Group 3 and Group 4, exposed to 80 W microwave power, displayed electric field levels of approximately 1450 V/m, while remaining free from any observable electrical discharges. The migratory and invasive capacities of PC3 cells were assessed through a scratch test in all groups. Notably, cells in Group 3 and Group 4, subjected to the combined treatment of microwave ablation and PEMF, demonstrated significantly accelerated migration in comparison to those in Groups 1 and 2. Additionally, Group 5 cells, receiving PEMF treatment in isolation, exhibited decreased migratory ability. These results strongly suggest that the combined approach of microwave ablation and PEMF holds promise as a potential therapeutic intervention for prostate cancer, as it effectively reduced cell viability, induced apoptosis, and impeded migration ability in PC3 cells. Moreover, the isolated use of PEMF demonstrated potential in limiting migratory capacity, which could hold critical implications in the fight against cancer metastasis.

High-intensity focused ultrasound with visually directed power adjustment for focal treatment of localized prostate cancer: systematic review and meta-analysis

PURPOSE

To characterize patient outcomes following visually directed high-intensity focused ultrasound (HIFU) for focal treatment of localized prostate cancer.

METHODS

We performed a systematic review of cancer-control outcomes and complication rates among men with localized prostate cancer treated with visually directed focal HIFU. Study outcomes were calculated using a random-effects meta-analysis model.

RESULTS

A total of 8 observational studies with 1,819 patients (median age 67 years; prostate-specific antigen 7.1 mg/ml; prostate volume 36 ml) followed over a median of 24 months were included. The mean prostate-specific antigen nadir following visually directed focal HIFU was 2.2 ng/ml (95% CI 0.9-3.5 ng/ml), achieved after a median of 6 months post-treatment. A clinically significant positive biopsy was identified in 19.8% (95% CI 12.4-28.3%) of cases. Salvage treatment rates were 16.2% (95% CI 9.7-23.8%) for focal- or whole-gland treatment, and 8.6% (95% CI 6.1-11.5%) for whole-gland treatment. Complication rates were 16.7% (95% CI 9.9-24.6%) for de novo erectile dysfunction, 6.2% (95% CI 0.0-19.0%) for urinary retention, 3.0% (95% CI 2.1-3.9%) for urinary tract infection, 1.9% (95% CI 0.1-5.3%) for urinary incontinence, and 0.1% (95% CI 0.0-1.4%) for bowel injury.

CONCLUSION

Limited evidence from eight observational studies demonstrated that visually directed HIFU for focal treatment of localized prostate cancer was associated with a relatively low risk of complications and acceptable cancer control over medium-term follow-up. Comparative, long-term safety and effectiveness results with visually directed focal HIFU are lacking.

Patient-reported prostate cancer treatment regret following primary partial gland cryoablation

BACKGROUND

Prostate cancer treatment-related regret (TRR) incorporates the myriad effects of diagnosis and treatment with associated behavioral, emotional, and interpersonal changes within the context of patient values and expectations. We aimed to investigate TRR following primary partial gland cryoablation (PPGCA).

METHODS

Men with prostate cancer undergoing PPGCA since 3/2017 enrolled in a prospective outcome registry. Between June and August 2022, a validated prostate cancer related TRR decision scale was distributed. TRR score ≥40 was considered significant TRR. Men were considered potent if they reported ability to have penetration at least half the time sexual intercourse was initiated. Associations between significant TRR and baseline characteristics and longitudinal outcomes were assessed using logistic regressions.

RESULTS

Of 245 men who met inclusion criteria, 163 (67%) completed the survey with median time since cryoablation 2.3 years (IQR: 1.3, 3.6). Overall, the mean composite TRR score was 12.4/100. Significant TRR was expressed by 14% of men. Among those who were potent/had erectile function at baseline, loss of potency and erectile function were associated with higher probability of significant TRR, respectively. No associations were identified between TRR and recurrence of clinically significant prostate cancer or salvage treatment.

CONCLUSIONS

The overwhelming majority of men do not express TRR following PPGCA. The loss of potency or development of erectile dysfunction predisposes to TRR. It is imperative to elucidate short-, intermediate- and long-term functional and oncological outcomes in order to define factors associated with TRR to improve counseling and reduce patient regret.

An Update on Focal Therapy for Prostate Cancer

Radical treatments and active surveillance are valid therapeutic approaches for low-risk prostate cancer. The oncologic effectiveness and morbidity of Radical Prostatectomy (RP) and radiotherapy have been broadly validated. Focal therapies pursue to reduce the morbidity observed after radical treatments, while preserving the oncologic effectiveness. This study aims to review the state-of-the-art about principles, oncologic effectiveness, morbidity, and side-effects associated with leading focal therapies. We review and summarize articles related with Cryotherapy, High-Intensity Focal Ultrasound (HIFU), Photodynamic Therapy (PDT), and Irreversible Electroporating (IRE) published in MEDLINE from 2000 to 2022. There is a wide heterogeneity in terms of the measurement of effectiveness and morbidity. Hence, comparing different energies, strategies and protocols seem to be unprecise and controversial. Cryosurgery and HIFU have reported more clinical experience than PDT and IRE. Biochemical recurrence rate after the first session varied from 4.5% to 23%, and up to 20% of patients underwent a salvage radical treatment. The reported incidence of erectile disfunction and urinary incontinence ranges from 3% to 50% and 0% to 34%, respectively. None randomized clinical trial comparing any focal therapy to any radical treatment has been published. We conclude that the expansion of focal therapies requires the consolidation of MRI-guided fusion biopsies in everyday clinical practice. Short-term oncologic effectiveness has been proved and supports their usefulness in low-risk patients unfit for surgical treatment. However, long-term effects and the clinical experience in intermediate and high-risk patients remains limited. Currently none of the focal therapies can be considered the Gold Standard for low-risk patients.

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.

Focal Cryoablation of the Prostate: Primary Treatment in 163 Patients With Localized Prostate Cancer

Objective Whole gland treatment of the prostate has known efficacy in treating many grades of prostate cancer. However, it is often associated with increased morbidity, including erectile dysfunction and urinary incontinence. Focal ablative therapies, including focal cryoablation (FC), are utilized to minimize the risk of tumor progression and preserve erectile and urinary function. There is little to no consensus on whether intermediate or high-risk prostate cancer should be treated with focal therapy. However, there is a growing body of literature on the effectiveness of FC as an effective means of prostate cancer control. We characterize our experience with 163 patients who underwent FC with a median follow-up of 39 months (IQR: 24-60). Methods A 163-patient retrospective cohort underwent FC of the prostate at a single clinic by a physician from November 2008 to December 2020. Each of these T1c patients in this single-tail study was monitored for biochemical recurrence (BCR) and oncologic outcomes. American Society for Radiation Oncology (ASTRO) definition of BCR is three consecutive prostate-specific antigens (PSA) increases of more than 0.5 ng/mL or, along with the utilization of the Phoenix definition, a PSA greater than nadir by 2 ng/mL was used to define BCR. This study's primary endpoint includes BCR or biochemical disease-free survival rates. Secondary endpoints include patient side effects, such as measuring for urinary incontinence and outcomes of salvage treatments. Cox proportional hazard analyses defined univariate HRs and 95% CIs for pre-operative PSA (POPSA), Decipher, and Gleason Grade Groups (GGGs) to determine the prognostic impact of pathologic factors. Statistical analysis and BCR timeline analysis also included logistic regression and the Kaplan-Meier method, with significance considered at p < 0.05. Select focal cryotherapy patients were monitored utilizing genomic sequencing tests. Results Our cohort included 27 patients (16.5%) with D'Amico low, 115 patients (70.5%) with intermediate, and 23 patients (14.1%) with high-risk prostate cancers. One month after FC, a 73% reduction in PSA resulted in a median post-operative PSA of 1.39 ng/mL (IQR: 0.46-2.80 ng/mL). At five years, our cohort yielded biochemical disease-free recurrence rates of 78%, 74%, and 55% for low, intermediate, and high-grade cancers, respectively. Genetic risk stratification results showed very similar BCR rates to patients whose tissues did not undergo genomic testing, at 27%, 26%, and 46% for low, intermediate, and high-grade cancers, respectively. Log-rank tests to map for BCR and HRs for pathologic factors did not yield any statistically significant predictive results. Urinary incontinence and erectile dysfunction were reported in 1.8% and 3.1% of patients in the focal cohort. Conclusions Our results add to the expanding body of literature around the efficacy of focal ablative therapies in contrast to whole gland treatment. The definitive extent of FC's efficacy still remains to be explored, but our conclusions demonstrate favorable PSA kinetics at five years follow-up.

Time-course changes in multiparametric magnetic resonance imaging following focal cryotherapy for localized prostate cancer: Initial experience

PURPOSE

To evaluate the time-course changes of multiparametric MRI findings following focal cryotherapy for localized prostate cancer.

METHODS

Sixteen patients who underwent focal cryotherapy as an initial curative treatment for localized prostate cancer during March 2017-April 2021 were included. Before the treatment, the patients underwent targeted prostate biopsy using MRI-transrectal ultrasound fusion. Overall, 64 MRIs were conducted after focal cryotherapy and the temporal post-treatment MR signal changes of the ablated area in T2WI, T1WI, DWI, and DCE-MRI were analyzed.

RESULTS

Technical success was achieved in all patients. The median follow-up period was 22 months. The initial post-treatment MRI revealed significant signal changes in the target lesions for all patients, including the disappearance of findings suggestive of cancer. At 3 months post-treatment, most lesions were hyperintense with a hypointense rim on T2WI, T1WI, and DWI (83.3 %). After 6 months, hyperintensity reduced, and after 17 months, all lesions showed hypointensity in these sequences. DCE-MRI of most patients showed loss of internal enhancement; however, one patient exhibited residual nodular enhancement in the ablated area at 3 months, which disappeared after 6 months. Peripheral enhancement was common at 3 months, disappearing after 23 months. Two patients showed biopsy-evidenced local recurrence. The recurrent lesions showed hypointensity on T2WI with diffusion restriction and early contrast enhancement in the ventral transition zone.

CONCLUSION

MRI findings of the ablated sites following focal cryotherapy for localized prostate cancer show dynamic signal changes, especially within the first 6 months.

Two Year Functional Outcomes Stratified According to Baseline Erectile Function Following Partial Gland Cryo-Ablation

OBJECTIVE

To critically evaluate time dependent sexual function following primary partial gland cryo-ablation (PGCA) stratified according to baseline erectile function.

METHODS

Between March 2017 and March 2022, all men undergoing primary PGCA by 2 surgeons were enrolled in an IRB approved outcomes registry. All subjects with PIRADS 2-5 lesion concordant with unilateral GGG 1-3 disease, no gross extra-prostatic extension on mpMRI, GGG >1 contralateral to the ROI, or distal apical disease on mpMRI were enrolled. Patients completed the Sexual Health Inventory for Men (SHIM) scale at baseline, 6, and 24 months. Men were stratified by baseline erectile function. Men with SHIM Score < 8 were excluded. Ability to sustain erection (aka "potency") was defined as a score of 3 or greater on question 2 of the SHIM index. Median SHIM scores and the proportion of men reporting "potency" at baseline, 6, and 24 months was recorded with comparisons between each timepoint. A univariate analysis was used to determine if clinical factors were associated with loss of "potency" at 24 months.

RESULTS

106 men met the inclusion criteria. There was a statistically significant decrease in the mean SHIM scores for the entire cohort between baseline to 6 months and baseline to 24 months. SHIM scores increased significantly for the total cohort between 6 and 24 months. "Potency" was preserved in 70% at 24 months.

CONCLUSION

Those patients most likely to exhibit a decrease in sexual function have moderate ED at baseline. Only baseline ED was shown to predict preservation of "potency".

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.

mpMRI-US Fusion-Guided Targeted Cryotherapy in Patients with Primary Localized Prostate Cancer: A Prospective Analysis of Oncological and Functional Outcomes

Simple Summary

Targeted cryotherapy is an emerging treatment for prostate cancer (PCa). mpMRI is a powerful tool for image fusion techniques that deliver incremental precision in diagnostic and treatment of PCa. Fusion targeted cryotherapy (FTC) arises from the simultaneous application of both these procedures. Recurrence is a concern after any type of PCa treatment, especially after targeted treatments. In this article we investigate the recurrence rate after FTC and the role of Prostate-Specific Antigen (PSA) as a predictor of recurrences. Our research provides new evidence on the feasibility of FCT by providing new insights on patient management.

Abstract

Targeted therapy (TT) for prostate cancer (PCa) aims to ablate the malignant lesion with an adequate margin of safety in order to obtain similar oncological outcomes, but with less toxicity than radical treatments. The main aim of this study was to evaluate the recurrence rate (RR) in patients with primary localized PCa undergoing mpMRI/US fusion targeted cryotherapy (FTC). A secondary objective was to evaluate prostate-specific antigen (PSA) as a predictor of recurrences. We designed a prospective single-center single-cohort study. Patients with primary localized PCa, mono or multifocal lesions, PSA ≤ 15 ng/mL, and a Gleason score (GS) ≤ 4 + 3 undergoing FTC were enrolled. RR was chosen as the primary outcome. Recurrence was defined as the presence of clinically significant prostate cancer in the treated areas. PSA values measured at different times were tested as predictors of recurrence. Continuous variables were assessed with the Bayesian t-test and categorical assessments with the chix-squared test. Univariate and logistic regression assessment were used for predictions. A total of 75 cases were included in the study. Ten subjects developed a recurrence (RR: 15.2%), while fifty-six (84.8%) patients showed a recurrence-free status. A %PSA drop of 31.5% during the first 12 months after treatment predicted a recurrence with a sensitivity of 53.8% and a specificity of 79.2%. A PSA drop of 55.3% 12 months after treatment predicted a recurrence with a sensitivity of 91.7% and a specificity of 51.9%. FTC for primary localized PCa seems to be associated with a low but not negligible percentage of recurrences. Serum PSA levels may have a role indicating RR.

High-Intensity Focused-Ultrasound Focal Therapy Versus Laparoscopic Radical Prostatectomy: A Comparison of Oncological and Functional Outcomes in Low- and Intermediate-Risk Prostate Cancer Patients

To compare oncological and functional outcomes of high-intensity focused-ultrasound (HIFU) focal therapy (FT) versus laparoscopic radical prostatectomy (LRP) in patients treated for low- or intermediate-risk prostate cancer (PCa), we retrospectively analyzed data of consecutive patients comprising 30 men, who underwent HIFU-FT, and 96 men who underwent LRP, in an academic center. Oncological outcomes were assessed based on the follow-up prostate-specific antigen values. We used the International Index of Erectile Function short form score to assess erectile function (EF). Urinary continence status was defined based on the number of pads used per day. Median follow-up was 12.5 and 19.1 months in the LRP and HIFU-FT groups, respectively. The effects were computed after propensity score matching and expressed as average treatment effect (ATE). Compared to LRP, HIFU-FT was associated with increased risk of treatment failure (ATE 0.103–0.164, depending on definition, p < 0.01) and lower risk of urinary incontinence (ATE −0.808 at 12 months, p < 0.01). Risk of erectile dysfunction was higher in the LRP group (ATE 5.092, p < 0.01). Our results demonstrate that HIFU-FT may be a reasonable treatment option in selected PCa patients, willing to preserve their EF and urinary continence yet accepting a higher risk of treatment failure.

Evolution of Focal Therapy in Prostate Cancer: Past, Present, and Future

Organ sparing approaches for the management of localized prostate cancer were developed in part to overcome the morbidity associated with standard, whole gland treatment options. The first description of focal therapy was now over two decades ago and since that time much has changed. The evolution of patient selection, the approach to ablation, and surveillance after focal therapy have mirrored the technologic advancements in the field as well as the improved understanding of the biology of low-grade, low-risk prostate cancer. This review presents the evidence for the basis of focal therapy from the past to the present and future endeavors.

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.

Focal Cryoablation of Image-Localized Prostate Cancer

Focal cryoablation of localized prostate cancer can offer patients superior genitourinary functional outcomes in terms of preservation of urinary continence and potency compared with radical whole-gland therapy, while maintaining intermediate-term oncologic control. We present a step-by-step guide to focal cryoablation of localized prostate cancer. A patient with elevated prostate specific antigen (PSA) underwent multiparametric MRI (mpMRI) of the prostate that revealed a prostate imaging-reporting and data system (PI-RADS) four lesion. The patient subsequently had a transrectal ultrasound (TRUS)-guided MRI fusion biopsy of the target lesion as well as a systematic biopsy and was only found to have Gleason 3 + 4 prostate cancer in the 0.5 cc mpMRI target. The lesion plus a treatment margin was ablated with cryotherapy utilizing a traditional transperineal approach. Patient position, ultrasound and mpMRI image fusion, insertion of cryoablation needles, ablation of the prostate cancer lesion, and postoperative care were reviewed. Equipment used during the operation was itemized and described. This guide explores the necessary equipment, procedural steps, and tips for success when performing focal cryoablation of the prostate. The technique described represents the culmination of knowledge gathered with 30 years of experience performing cryoablation of prostate cancer. The accompanying video highlights the utilization of mpMRI and TRUS image fusion, triangulation of lethal ice around the prostate cancer lesion, and the importance of monitoring real-time ice formation with TRUS imaging. Cryoablation of prostate cancer can be applied to several clinical scenarios: partial-gland ablation, quadrant, hemiablation, focal-targeted, or whole gland in the primary or salvage settings. We present the surgical steps that are essential for effective focal ablation of image-localized prostate cancer.

Prospective trial of regional (hockey-stick) prostate cryoablation: oncologic and quality of life outcomes

PURPOSE

To report long-term follow-up of the efficacy of subtotal prostate ablation using a "hockey-stick" template, including oncologic control and quality of life (QoL) impact.

METHODS

We performed a prospective controlled trial to evaluate the efficacy of subtotal prostate ablation in selected men with baseline and confirmatory biopsy showing grade group (GG) 1-2 prostate cancer. "Hockey-stick" cryoablation that included the ipsilateral hemi-gland and contralateral anterior prostate was performed. Prostate biopsies and QOL queries were performed at 6, 18 and 36 months following regional ablation, and follow-up was updated to include subsequent clinic visits.

RESULTS

Between August 2009 and January 2012, 72 men were screened for eligibility and 47 opted to undergo confirmatory biopsy. Of these, 23 were deemed eligible and treated with regional cryoablation. Median age was 64 years. Median follow-up was 74 months. A single patient had < 1 mm of in-field viable tumor with therapy effect on 36-month biopsy. At time of last follow-up, a total of 12/23 (52%) patients did not have evidence of disease, all patients had preserved urinary control with no patients requiring pads for urinary incontinence. Sexual decline was significant at 3 and 6 months (P < 0.01 for both), though improvement was seen at subsequent time points.

CONCLUSION

Subtotal (hockey-stick template) cryoablation of the prostate provides oncologic control to targeted tissue in a generally low-risk group with minimal impact on sexual and urinary function. Further studies are needed to evaluate this ablation template in the MRI-targeted era and higher risk populations.

The Impact of Placement Errors on the Tumor Coverage in MRI-Guided Focal Cryoablation of Prostate Cancer

RATIONALE AND OBJECTIVES

There have been multiple investigations defining and reporting the effectiveness of focal cryoablation as a treatment option for organ-confined prostate cancer. However, the impact of cryo-needle/probe placement accuracy within the tumor and gland has not been extensively studied. We analyzed how variations in the placement of the cryo-needles, specifically errors leading to incomplete ablation, may affect prostate cancer's resulting cryoablation.

MATERIALS AND METHODS

We performed a study based on isothermal models using Monte Carlo simulations to analyze the impact of needle placement errors on tumor coverage and the probability of positive ablation margin. We modeled the placement error as a Gaussian noise on the cryo-needle position. The analysis used retrospective MRI data of 15 patients with biopsy-proven, unifocal, and MRI visible prostate cancer to calculate the impact of placement error on the volume of the tumor encompassed by the -40°C and -20°C isotherms using one to four cryo-needles.

RESULTS

When the standard deviation of the placement error reached 3 mm, the tumor coverage was still above 97% with the -20°C isotherm, and above 81% with the -40°C isotherm using two cryo-needles or more. The probability of positive margin was significantly lower considering the -20°C isotherm (0.04 for three needles) than using the -40°C isotherm (0.66 for three needles).

CONCLUSION

The results indicated that accurate cryo-needle placement is essential for the success of focal cryoablation of prostate cancer. The analysis shows that an admissible targeting error depends on the lethal temperature considered and the number of cryo-needles used.

Multifunctional nanostructured drug delivery carriers for cancer therapy: Multimodal imaging and ultrasound-induced drug release

Development of multimodal systems for therapy and diagnosis of neoplastic diseases is an unmet need in oncology. The possibility of simultaneous diagnostics, monitoring, and therapy of various diseases allows expanding the applicability of modern systems for drug delivery. We have developed hybrid particles based on biocompatible polymers containing magnetic nanoparticles (MNPs), photoacoustic (MNPs), fluorescent (Cy5 or Cy7 dyes), and therapeutic components (doxorubicin). To achieve high loading efficiency of MNP and Dox to nanostructured carriers, we utilized a novel freezing-induced loading technique. To reduce the systemic toxicity of antitumor drugs and increase their therapeutic efficacy, we can use targeted delivery followed by the remote control of drug release using high intensity-focused ultrasound (HIFU). Loading of MNPs allowed performing magnetic targeting of the carriers and enhanced optoacoustic signal after controlled destruction of the shell and release of therapeutics as well as MRI imaging. The raster scanning optoacoustic mesoscopy (PA, RSOM), MRI, and fluorescent tomography (FT) confirmed the ultrasound-induced release of doxorubicin from capsules: in vitro (in tubes and pieces of meat) and in vivo (after delivery to the liver). Disruption of capsules results in a significant increase of doxorubicin and Cy7 fluorescence initially quenched by magnetite nanoparticles that can be used for real-time monitoring of drug release in vivo. In addition, we explicitly studied cytotoxicity, intracellular localization, and biodistribution of these particles. Elaborated drug delivery carriers have a good perspective for simultaneous imaging and focal therapy of different cancer types, including liver cancer.

Cryoablation, high-intensity focused ultrasound, irreversible electroporation, and vascular-targeted photodynamic therapy for prostate cancer: a systemic review and meta-analysis

Cryoablation (CA), high-intensity focused ultrasound (HIFU), irreversible electroporation (IRE), and vascular-targeted photodynamic therapy (VTP) have been evaluated as novel strategies for selected patients with prostate cancer (PCa). We aim to determine the current status of literature regarding the clinical outcomes among these minimally invasive therapies. A systematic search of PubMed, EMBASE, and the Cochrane Library for all English literature published from January 2001 to December 2019 was conducted to identify studies evaluating outcomes of CA, HIFU, IRE or VTP on PCa. Proportionality with 95% confidence intervals (CIs) was performed using STATA version 14.0. 56 studies consisting of 7383 participants were found to report data of interest and fulfilled the inclusion criteria in the final meta-analysis. The pooled proportions of positive biopsy after procedure were 20.0%, 24.3%, 24.2%, and 36.2% in CA, HIFU, IRE and VTP, respectively. The pooled proportions of BRFS were 75.7% for CA and 74.4% for HIFU. The pooled proportions of CSS were 96.1%, 98.2%, and 97.9% for CA, HIFU, and IRE, respectively. The pooled proportions of OS were 92.8% for CA and 85.2% for HIFU. The pooled proportions of FFS were 64.7%, 90.4%, and 76.7% for CA, IRE and VTP, respectively. The pooled proportions of MFS were 92.8% for HIFU and 99.1% for IRE. This meta-analysis shows that CA, HIFU, IRE, and VTP are promising therapies for PCa patients with similar clinical outcomes. However, further larger, well-designed randomized controlled trials are required to confirm this assertion.

The role of prostate-specific antigen in light of new scientific evidence: An update in 2020

OBJECTIVE

To review and update the latest scientific evidence gathered in recent years regarding prostate-specific antigen (PSA) for better implementation into routine clinical practice.

EVIDENCE ACQUISITION

Analysis of the available evidence on the current role of PSA, based on the experience of an expert panel in the subject under analysis.

EVIDENCE SYNTHESIS

Currently, PSA cannot be considered only as a guide for the presence or absence of prostate cancer. This determination can also help the urologist to decide on the most convenient treatment for a patient with benign prostatic hypertrophy (BPH) as a criterion for disease progression, and it can also suggest the suspicious existence of a prostatic tumor when there is PSA rise of>0.3 ng/ml over the level reached 6 months after having initiated treatment with 5-alpha-reductase inhibitor. However, the limits of this PSA rise with derivatives of alternative 5-alpha-reductase (5-ARI) inhibitors to dutasteride are controversial. Moreover, PSA is a key factor for the follow-up of patients with prostate adenocarcinoma at any stage who have received treatment (surgery, radiotherapy or focal therapies, hormone therapy), it acts as a guide to identify biochemical recurrence, to suspect the existence of local or distant recurrence, as well as to propose or discard adjuvant treatments. Finally, the role of PSA as a screening tool has been recently reinforced, demonstrating increased mortality rates or the existence of more aggressive cases of prostate cancer in those countries where the use of this tool has declined.

CONCLUSIONS

We present new data about the current role of PSA in the management of patients treated for BPH and/or prostate cancer that should be implemented into routine clinical practice, with special emphasis on the relevant role of this biomarker in the screening and follow-up of prostate cancer, as well as in the progression of BPH in dutasteride treatment.

Biomechanically constrained non-rigid MR-TRUS prostate registration using deep learning based 3D point cloud matching

A non-rigid MR-TRUS image registration framework is proposed for prostate interventions. The registration framework consists of a convolutional neural networks (CNN) for MR prostate segmentation, a CNN for TRUS prostate segmentation and a point-cloud based network for rapid 3D point cloud matching. Volumetric prostate point clouds were generated from the segmented prostate masks using tetrahedron meshing. The point cloud matching network was trained using deformation field that was generated by finite element analysis. Therefore, the network implicitly models the underlying biomechanical constraint when performing point cloud matching. A total of 50 patients' datasets were used for the network training and testing. Alignment of prostate shapes after registration was evaluated using three metrics including Dice similarity coefficient (DSC), mean surface distance (MSD) and Hausdorff distance (HD). Internal point-to-point registration accuracy was assessed using target registration error (TRE). Jacobian determinant and strain tensors of the predicted deformation field were calculated to analyze the physical fidelity of the deformation field. On average, the mean and standard deviation were 0.94±0.02, 0.90±0.23 mm, 2.96±1.00 mm and 1.57±0.77 mm for DSC, MSD, HD and TRE, respectively. Robustness of our method to point cloud noise was evaluated by adding different levels of noise to the query point clouds. Our results demonstrated that the proposed method could rapidly perform MR-TRUS image registration with good registration accuracy and robustness.

Standardized Nomenclature and Surveillance Methodologies After Focal Therapy and Partial Gland Ablation for Localized Prostate Cancer: An International Multidisciplinary Consensus

BACKGROUND

Focal therapy (FT) and partial gland ablation (PGA) are quickly adopted by urologists and radiologists as an option for the management of localized prostate cancer.

OBJECTIVE

To find consensus on a standardized nomenclature and to define a follow-up guideline after FT and PGA for localized prostate cancer in clinical practice.

DESIGN, SETTING, AND PARTICIPANTS

A review of the literature identified controversial topics in the field of FT. Online questionnaires were distributed to experts during three rounds, with the goal to achieve consensus on debated topics. The consensus project was concluded with a face-to-face meeting in which final conclusions were formulated.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Controlled feedback of responses of previous rounds were summarized and returned to the participants allowing them to re-evaluate their decisions. The level of agreement to achieve consensus on a topic was set at 80%.

RESULTS AND LIMITATIONS

Sixty-five experts participated in this interdisciplinary consensus study (72% urologists; 28% radiologists). The experts propose the use of the herein standardized nomenclature for ablative procedures. After FT/PGA, the following tests should be performed to assess treatment outcomes: prostate-specific antigen (PSA), imaging, biopsies, and functional outcome assessment. Although not a reliable marker for treatment failure, PSA should be measured every 3 mo in the 1st year and every 6 mo thereafter. Magnetic resonance imaging is the preferred image modality and should be performed at 6 and 18 mo after treatment. A systematic 12-core transrectal ultrasound-guided biopsy combined with a targeted biopsy of the treated area should be performed 6-12 mo after treatment. Functional outcomes should be obtained 3-6 mo after treatment for the first time and until stability is attained.

CONCLUSIONS

The panel recommends the use of the proposed nomenclature and follow-up protocols to generate reliable data supporting a broader implementation of FT as a standard of care for select patients with localized prostate cancer.

PATIENT SUMMARY

In this report, we present expert opinion on the use of a standardized nomenclature, and surveillance methodologies after focal therapy and partial gland ablation for localized prostate cancer.

Focal bipolar radiofrequency ablation for localized prostate cancer: Safety and feasibility

OBJECTIVES

To evaluate the safety and feasibility of focal bipolar radiofrequency ablation in men with localized prostate cancer.

METHODS

A review of 10 patients treated with a novel bipolar radiofrequency ablation probe integrated in a coil design (Encage; Trod Medical, Bradenton, FL, USA) between 2011 and 2017 in two prospective pilot trials. All men had clinical stage T1c prostate cancer, prostate-specific antigen <10 ng/mL and Gleason score ≤7. Ablation was carried out under general anesthesia, and bipolar probes were inserted transperineally under transrectal ultrasound guidance. Treatment-related adverse events, quality of life and negative biopsy rate were evaluated at 6 months after ablation. The Wilcoxon signed-rank test was used to compare baseline and post-treatment symptom scores.

RESULTS

The median age was 58 years (range 50-64 years) and the median prostate volume was 49.65 cc (range 21-68 cc). Prostate cancer with a Gleason score of 6 (3 + 3) and 7 (3 + 4) was noted in seven and three patients, respectively. The median number of radiofrequency ablation cycles was 2.5 (range 2-5). All patients were catheter-free and able to void the day of surgery. Within 6 months after ablation, all adverse events were low grade, with the exception of one grade 3 hematuria that required cystoscopy without coagulation. Six months after ablation bowel, urinary and hormonal functions, and overall satisfaction remained stable. Erectile dysfunction occurred in two out of four patients who had normal sexual function before the procedure. Neither urinary incontinence nor urinary infection was noted.

CONCLUSIONS

This first report on focal bipolar radiofrequency ablation documents a safe and feasible treatment option for selected patients with localized prostate cancer.

Cryotherapy shows no inferiority compared with radical Prostatectomy for low-risk and intermediate-risk localized Prostate Cancer: a real-world study from the SEER database

Background: For localized prostate cancer (PCa) with a low disease burden, whole-gland resection seems like overtreatment, while focal therapy, including cryosurgery, can achieve similar outcomes. We aimed at comparing the long-term survival outcomes of cryotherapy and radical prostatectomy (RP) and further exploring whether RP can be replaced by cryosurgery for those with low-risk PCa.

Methods: We conducted analyses from the Surveillance, Epidemiology, and End Results (SEER) database (2004-2015) and performed propensity score matching and used an instrumental variate to reduce the influence of bias and unmeasured confounders to the greatest extent.

Results: In the multivariate regression, patients who received cryotherapy had higher risk of overall mortality (OM) (hazard ratio [HR] = 2.52, 95% confidence interval [CI] 1.99-3.20, p < 0.001), but no significant difference was observed in decreasing cancer-specific mortality (CSM) (HR = 1.38, 95% CI 0.63-3.03, p = 0.41) after adjusting the confounders. After propensity score matching, patients who underwent cryotherapy had higher OM and CSM rates (HR = 2.70 [95% CI 1.99-3.66, p < 0.001] and HR = 2.99 [95% CI 1.19-7.48, p = 0.02], respectively). In the IV-adjusted analyses, RP was superior to cryotherapy in decreasing OM (HR = 2.52, 95% CI 1.99-3.20), while no obvious decrease of CSM was observed in the comparison of RP and cryotherapy (HR = 1.38, 95% CI 0.63-3.03). The subgroup analyses showed that RP displayed an obvious benefit in decreasing CSM (HR = 5.02, 95% CI 1.30-19.39, p = 0.02) for those with a prostate-specific antigen (PSA) level higher than 10 ng/ml.

Conclusion: RP ranked as the best treatment in regard to tumor control, but the advantages of cryotherapy became evident when taking functional and oncological outcomes into account, especially for low- and intermediate-risk PCa with low PSA levels.

Targeting the cancer lesion, not the whole prostate

Modern cancer treatment aims to conserve as much healthy tissue as possible. This has been challenging in the treatment of prostate cancer due to the difficulty in imaging the gland and concerns over leaving multifocal cancer untreated. With improvements in imaging and understanding of multifocal prostate cancer evidence now shows accurate treatment of just the primary focus of cancer or the index lesion can control progression or recurrence of the disease. Many different energy sources are now available to target the cancer lesion within the prostate with less significant side-effects on urinary and sexual function compared to radical treatment. Evidence shows that men value these functions highly and would even trade years of life in exchange for preserved retention of continence or erectile function. Focal treatment of prostate cancer aims to provide both cancer control and preservation of sexual and urinary functions so that men do not have to make a choice between the two. This is a treatment option that men clearly want and deserve.

Whole and hemi-gland cryoablation for primary localized prostate cancer: Short and medium-term oncological and functional outcomes

INTRODUCTION

To compare oncological, functional and post-operative outcomes of hemi (HC) vs. whole gland (WGC) cryoablation as first line treatment of localized prostate cancer.

MATERIAL AND METHOD

Sixty-six consecutive patients undertaking whole-gland cryoablation (WGC=40) or hemi-cryoablation (HC=26) in a tertiary referral centre between 2010 and 2018 were included. All patients had a low-intermediate risk prostate cancer according to D'Amico risk classification. Hemi-ablation was proposed in case of biopsy and prostate MRI proven unilateral prostate cancer. Primary endpoint was Cryotherapy Failure for which 3 definitions were considered and compared: 1) biochemical failure (> PSA nadir+≥ 2 ng/mL), 2) positive prostate re-biopsy with Gleason score ≥ 7, 3) initiation of further prostate cancer treatment.

RESULTS

Median patients age at treatment was 74 [42-81] vs. 76 [71-80] years in WGC vs. HC group, respectively (p=.08). Low and intermediate D'Amico risk group were 15% and 85% vs. 23% and 77% (p=.75), respectively. Median follow- up time was 41 [1.5-99.0] vs. 27 [0.9-93] months (p=.03). Four-years cryotherapy failure free survival in WGC vs. HC were 69% vs. 53% with definition 1 (p=.24), 82% vs. 80% with definition 2 (p=.95), 83% vs. 77% with definition 3 (p=.73). Early and 1-year urinary continence were 60% and 83% in WGC vs. 72% and 83% in HC (p=.26). De novo impotency after cryotherapy was 75% vs. 46% (p=.33) in WGC vs. HC.

CONCLUSIONS

In our cohort of highly selected patients with unilateral low/intermediate risk PCa, hemi-cryoablation may provide similar oncological outcomes and less early complications compared to whole-gland cryoablation.

Focal therapy for localized prostate cancer in the era of routine multi-parametric MRI

BACKGROUND

Prostate cancer focal therapy aims to minimize the side-effects of whole gland treatments, such as radical prostatectomy and radiotherapy without compromising oncological efficacy. However, concerns exist regarding the multifocal nature of prostate cancer and the lack of long-term oncological data for this form of treatment. In recent years, the routine adoption of multi-parametric magnetic resonance imaging (mpMRI) of the prostate has improved our ability to select candidates for focal therapy and to accurately deliver this form of prostate cancer treatment.

METHODS

We performed a review of the literature to provide a summary of the oncological and functional outcomes of men receiving primary prostate focal therapy. Furthermore, we discuss the impact of the routine implementation of mpMRI as part of the initial prostate cancer diagnostic pathway on the selection of candidates and delivery of focal therapy. Finally, we summarize knowledge gaps in the field and highlight active clinical trials in this arena.

RESULTS

Primary focal therapy involves the application of one of a number of energies that ablate tissue, such as cryotherapy and high intensity focused ultrasound (HIFU). Success is principally dependent on highly accurate patient selection and disease localization underpinned in large part by the routine integration of pre-biopsy mpMRI. Prospective medium-term follow-up data for primary HIFU and cryotherapy for men with intermediate-risk disease have shown acceptable cancer control with low risk of side effects and complications. Additional research is needed to clearly define an appropriate follow-up approach and to guide the management of in- and out-of-field recurrences. Multiple comparative trials with randomization against standard care are currently underway in men with intermediate- and high-risk prostate cancer.

CONCLUSION

The widespread adoption of prostate mpMRI has led to improved disease localization, enabling the performance of focal therapy as a viable treatment strategy for men with low volume intermediate-risk prostate cancer.

A polymeric paste-drug formulation for intratumoral treatment of prostate cancer

OBJECTIVE

Focal therapy has emerged as a treatment option for low- to intermediate-risk localized prostate cancer (PCa) patients, to balance the risks for urinary and sexual morbidity of radical treatment with the psychological burden of active surveillance. In this context, we developed ST-4PC, an injectable, polymeric paste formulation containing docetaxel (dtx) and bicalutamide (bic) for image-guided focal therapy of PCa. The objective of this work was to evaluate the in vitro characteristics and in vivo toxicity and efficacy of ST-4PC.

MATERIAL AND METHODS

In vitro drug release was evaluated using high-performance liquid chromatography. In vivo toxicity of blank- and drug-loaded ST-4PC was assessed in mice and rats. Tumor growth inhibition was evaluated in LNCaP subcutaneous (s.c.) and LNCaP-luc orthotopic xenograft models. Using the s.c. model, mice were monitored weekly for weight loss, tumor volume (TV) and serum PSA. For the orthotopic model, mice were additionally monitored for bioluminescence as measure of tumor growth.

RESULTS

ST-4PC demonstrated a sustained and steady release of incorporated drugs with 50% dtx and 20% bic being released after 14 days. While no systemic toxicity was observed, dose-dependent local side effects from dtx developed in the s.c. but not in the orthotopic model, illustrating the limitations of s.c. models for evaluating local cytotoxic therapy. In the s.c. model, 0.1%/4% and 0.25%/4% dtx/bic ST-4PC paste significantly reduced PSA progression, but did not have a significant inhibitory effect on TV. ST-4PC loaded with 1%/4% dtx/bic significantly reduced TV, serum PSA, and bioluminescence in the orthotopic xenograft model. Compared with drugs dissolved in DMSO, ST-4PC significantly delayed tumor growth.

CONCLUSION

Image-guided focal therapy using ST-4PC demonstrated promising inhibition of PSA progression and orthotopic tumor growth in vivo without significant toxicity, and warrants further clinical evaluation.

Does the Time Interval from Biopsy to Radical Prostatectomy Affect the Postoperative Oncologic Outcomes in Korean Men?

BACKGROUND

Prostate cancer (PC) is the second most common type of cancer in men worldwide and the fifth most common cancer among Korean men. Although most PCs grow slowly, it is unclear whether a longer time interval from diagnosis to treatment causes worse outcomes. This study aimed to investigate whether the time interval from diagnosis to radical prostatectomy (RP) in men with clinically localized PC affects postoperative oncologic outcomes.

METHODS

We retrospectively analyzed data of 427 men who underwent RP for localized PC between January 2005 and June 2016. The patients were divided into two groups based on the cutoff median time interval (100 days) from biopsy to surgery. The associations between time interval from biopsy to surgery (< 100 vs. ≥ 100 days) and adverse pathologic outcomes such as positive surgical margin, pathologic upgrading, and upstaging were evaluated. Biochemical recurrence (BCR)-free survival rates were analyzed and compared based on the time interval from biopsy to surgery.

RESULTS

Pathologic upgrading of Gleason score in surgical specimens was more frequent in the longer time interval group and showed marginal significance (38.8% vs. 30.0%; P = 0.057). Based on multivariable analysis, an association was observed between time interval from biopsy to surgery and pathologic upgrading (odds ratio, 2.211; 95% confidence interval [CI], 1.342-3.645; P = 0.002). BCR-free survival did not differ based on time interval from biopsy to surgery, and significant association was not observed between time interval from biopsy to surgery and BCR on multivariable analysis (hazard ratio, 1.285; 95% CI, 0.795-2.077; P = 0.305).

CONCLUSION

Time interval ≥ 100 days from biopsy to RP in clinically localized PC increased the risk of pathologic upgrading but did not affect long-term BCR-free survival rates in Korean men.

The Precision Prostatectomy: an IDEAL Stage 0, 1 and 2a Study

Objective

This study aimed to develop a preclinical model of prostate cancer (CaP) for studying focal/hemiablation of the prostate (IDEAL stage 0), and to use the information from the stage 0 investigation to design a novel focal surgical treatment approach—the precision prostatectomy (IDEAL stage 1/2a).

Methods

The IDEAL stage 0 study included simulation of focal/hemiablation in whole-mount prostate specimens obtained from 100 men who had undergone radical prostatectomies, but met the criteria for focal/hemiablation. The IDEAL stage 1/2a was a prospective, single-arm, Institutional Review Board-approved study of precision prostatectomy undertaken in eight men, who met the predetermined criteria. Criteria for both stages included (1) prostate-specific antigen (PSA) ≤15 ng/mL, (2) stage ≤cT2, (3) dominant unilateral lesion with Gleason ≤4+3 with any number of cores or % cores involved ipsilaterally on transrectal biopsy, (4) no primary Gleason ≥4 contralaterally on transrectal biopsy, and (5) preoperative erectile function score (International Index of Erectile Function (IIEF)-5) of ≥17 (out of 25) without PDE-5i (applicable only to the stage 1/2a study participants). Feasibility and safety of the precision prostatectomy technique, and short-term urinary, sexual and oncological outcomes were studied.

Results

Analysis of whole-mount specimens in the 100 men showed an index lesion (>1 cm in diameter) in all. Ninety-eight men had satellite lesions smaller than 0.5 cm∧3 in volume—46 on the side of the dominant lesions and 52 in the contralateral lobe. If the men in this modeling cohort had undergone focal ablation with a 5–10 mm untreated margin, all except one would have had at least Gleason 6 residual cancer. If they had undergone hemiablation with no untreated tissue on the ablated side, 56 men would have had residual cancer on the contralateral side, of whom 21 would have had clinically significant cancer (Gleason 7 or higher). If these men had undergone precision prostatectomy, with preservation of 5–10 mm of tissue on the non-dominant side, 10% and 4% would have had Gleason 3+4 and Gleason 4+3 disease left behind, respectively. For the stage 1/2a study, the median (IQR) age, PSA and IIEF-5 scores at the time of surgery were 54 (52–57) years, 4.4 (3.8–6.1) ng/mL and 24 (23-25), respectively. All eight patients were continent and sexually active at 12 months with a median IIEF-5 score of 21 (out of 25). At 24–30 months from surgery, the median PSA was 0.2 (range 0.1–0.7) ng/mL. Six men had undergone follow-up protocol biopsies, two, with undetectable PSA, had refused. Two men had residual Gleason 3+3 cancer, with PSA of 0.7 and 0.4 ng/mL, and remain on active surveillance. No man has undergone secondary whole-gland therapy.

Conclusions

Examination of whole-mount radical prostatectomy specimens in men who fit the conventional criteria of focal/hemiablation showed that approximately 21%–68% of men would have clinically significant CaP in the untreated tissue. In a small development cohort, precision prostatectomy was technically feasible, with excellent postoperative functional recovery. At 30 months of follow-up, no patient had clinically significant residual cancer or required secondary treatment. Pending long-term follow-up, a risk-stratified surgical approach may avoid whole-gland therapy and preserve erectile function in the majority of men with intermediate-risk CaP.

Prostate focal therapy: the rule or exception?

PURPOSE OF REVIEW

Prostate focal therapy has the potential to preserve urinary and sexual function while eliminating clinically significant cancer in a subset of men with low-volume, organ-confined prostate cancer. This systematic review aims to examine current evidence to determine the efficacy and safety of focal therapy for standard clinical application.

RECENT FINDINGS

Focal therapy reduces the rate of cancer progression and conversion to radical therapy in men on active surveillance for prostate cancer. As a strategy, success in focal therapy is heavily dependent on the use of imaging and targeted biopsies. Despite advances in these areas, there remains a small but significant risk of under-detecting clinically significant cancer. Similarly, under-estimation of tumor volume may contribute to infield recurrences and close attention must be paid to the ablation margin. Although long-term oncological outcomes remain lacking, focal therapy has a low complication rate, minimal impact on urinary continence and a moderate impact on erectile function.

SUMMARY

With the appropriate expertise in imaging, targeted biopsy and targeted ablation, focal therapy is a good option in men with low-intermediate risk cancer who are willing to maximize their urinary and sexual function. However, close posttreatment surveillance and the possibility of conversion to whole gland therapy must be accepted.

Percutaneous MR-guided prostate cancer cryoablation technical updates and literature review

Prostate cancer (PCa) is the most common malignant tumor in males. The benefits in terms of overall reduction in specific mortality due to the widespread use of Prostate Specific Antigen (PSA) screening and the advancements in the curative treatments (radical prostatectomy or radiotherapy) appear to have reached a plateau. There remains, however, the questions of overdiagnosis and overtreatment of such patients. Currently, the main challenge in the treatment of patients with clinically organ-confined PCa is to offer an oncologically efficient treatment with as little morbidity as possible. Amongst the arising novel curative techniques for PCa, cryoablation (CA) is the most established one, which is also included in the NICE and AUA guidelines. CA is commonly performed under ultrasound guidance with the inherent limitations associated with this technique. The recent advancements in MRI have significantly improved the accuracy of detecting and characterizing a clinically significant PCa. This, alongside the development of wide bore interventional MR scanners, has opened the pathway for in bore PCa treatment. Under MRI guidance, PCa CA can be used either as a standard whole gland treatment or as a tumor targeted one. With MR-fluoroscopy, needle guidance capability, multiplanar and real-time visualization of the iceball, MRI eliminates the inherent limitations of ultrasound guidance and can potentially lead to a lower rate of local complications. The aim of this review article is to provide an overview about PCa CA with a more specific insight on MR guided PCa CA; the limitations, challenges and applications of this novel technique will be discussed.

Do contemporary imaging and biopsy techniques reliably identify unilateral prostate cancer? Implications for hemiablation patient selection

BACKGROUND

Hemiablation is a less morbid treatment alternative for appropriately selected patients with unilateral prostate cancer (PCa). However, to the authors' knowledge, traditional diagnostic techniques inadequately identify appropriate candidates. In the current study, the authors quantified the accuracy for identifying hemiablation candidates using contemporary diagnostic techniques, including multiparametric magnetic resonance imaging (mpMRI) and MRI-fusion with complete systematic template biopsy.

METHODS

A retrospective analysis of patients undergoing MRI and MRI-fusion prostate biopsy, including full systematic template biopsy, prior to radical prostatectomy in a single tertiary academic institution between June 2010 and February 2018 was performed. Hemiablation candidates had unilateral intermediate-risk PCa (Gleason score [GS] of 3+4 or 4+3, clinical T classification ≤T2, and prostate-specific antigen level <20 ng/dL) on MRI-fusion biopsy and 2) no contralateral highly or very highly suspicious Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) MRI lesions. Hemiablation candidates were inappropriately selected if pathologists identified contralateral GS ≥3+4 or high-risk ipsilateral PCa on prostatectomy. The authors tested a range of hemiablation inclusion criteria and performed multivariable analysis of preoperative predictors of undetected contralateral disease.

RESULTS

Of 665 patients, 92 met primary hemiablation criteria. Of these 92 patients, 44 (48%) were incorrectly identified due to ipsilateral GS ≥3+4 tumors crossing the midline (21 patients), undetected distinct contralateral GS ≥3+4 tumors (20 patients), and/or ipsilateral high-risk PCa (3 patients) on prostatectomy. The rate of undetected contralateral disease ranged from 41% to 48% depending on inclusion criteria. On multivariable analysis, men with anterior index tumors were found to be 2.4 times more likely to harbor undetected contralateral GS ≥3+4 PCa compared with men with posterior lesions (P < .05).

CONCLUSIONS

Clinicians and patients must weigh the risk of inadequate oncologic treatment against the functional benefits of hemiablation. Further investigation into methods for improving patient selection for hemiablation is necessary.

Prostate cancer treated with irreversible electroporation: MRI-based volumetric analysis and oncological outcome

BACKGROUND

To assess multiparametric magnetic resonance imaging (mpMRI) characteristics in prostate cancer (PCa) before and after irreversible electroporation (IRE) and to investigate their correlation with the presence of post-operative recurrence of PCa.

METHODS

MpMRI was performed in 30 men with PCa prior to treatment, after 10 days and at 6 months. An additional scan at 1 year was available for 18 men. Two radiologists assessed retrospectively the following parameters by planimetry: tumour volume, necrotic volume (early post-treatment scan) and residual fibrosis. Residual tumour/recurrence were defined as a suspicious area within the treatment field scored ≥ 4 on a 1-to-5 scale. Oncological outcome was also assessed.

RESULTS

The median follow-up of the entire study was 16 months. Six men were undertreated and showed mpMRI recurrence after 6 months. At 1-year, three additional men had recurrence. Overall, four of these 9 men (44%) were retreated. The other five men did not receive any further treatment. Median time to re-treatment was 15 months. Median pre-treatment lesion volume was 0.65 cc, 0.66 cc and 0.43 cc on the different mpMRI sequences (T2-weighted, diffusion-weighted and dynamic contrast enhanced imaging). Median necrotic volume was 10.77 cc. Median overall residual fibrosis volumes were 0.84 cc and 0.95 cc at 6-month and 1-year mpMRI. Pre-treatment, necrotic and residual fibrosis volumes were significantly different (p < 0.001). Pre-treatment tumour volumes on diffusion-weighted imaging and necrotic volumes were correlated (r = 0.18; p = 0.02).

CONCLUSIONS

MpMRI is able to visualise the IRE ablation effects in men with PCa. MpMRI-derived parameters - such as tumour, necrotic and fibrosis volumes - can be measured and are potentially useful for assessing efficacy in the medium term, as with other ablative techniques.

Use of MRI-Guided Biopsy for Selection and Follow-up of Men Undergoing Hemi-gland Cryoablation of Prostate Cancer

OBJECTIVE

To investigate safety, efficacy, and quality of life impact of hemi-gland cryotherapy for clinically-significant prostate cancer (CaP), when patient selection and follow-up includes MRI-guided biopsy.

METHODS

Twenty-nine men with unilateral CaP (all clinically significant with prostate volume <60 cc) were enrolled in a prospective observational trial of hemi-gland cryotherapy. Mean patient age was 68.7 years. Median prostate-specific antigen (PSA) was 6.6 ng/mL. MRI-guided biopsy (3T-MRI, Artemis US fusion) was used for diagnosis and repeated at 6-month follow-up in all men. Treatment was under general anesthesia using the BTG/Galil system. Validated questionnaires were used to determine effects of treatment on urinary and sexual function and quality of life.

RESULTS

Cryotherapy was completed satisfactorily in all 29 cases in <60 minutes with no intraoperative complications. Significant decreases in PSA (median decrease 5.6 ng/mL) and PSA density (median decrease 0.14 ng/mL/cc) were observed (P < .01). At 6 months, 23 patients (79%) demonstrated no residual cancer on follow-up MRI-guided biopsy of the treated side. Three patients (10%) revealed micro-residual disease. Three patients (10%) had residual cancer and underwent further treatment. Ipsilateral MRI lesions were present before treatment in 26 patients and after treatment in only 2, reflecting the gross ablative effect; however, MRI showed disappearance of lesions in 4 patients with residual tumor on biopsy. The single complication was 1 case of transient urinary retention; 85% of men who were sexually active continued without change after treatment. Voiding function was unchanged.

CONCLUSION

Hemi-gland cryoablation for clinically-significant CaP is well-tolerated, and when patients are selected and followed by MRI/US fusion biopsy, cancer control appears promising at 6 months.

Primary Whole-gland Cryoablation for Prostate Cancer: Biochemical Failure and Clinical Recurrence at 5.6 Years of Follow-up

We retrospectively evaluated complications and functional and oncologic outcomes of 94 consecutive men who underwent primary whole-gland cryoablation for localized prostate cancer (PCa) from 2002 to 2012. Kaplan-Meier and multivariable Cox regression analyses were performed using a landmark starting at 6 mo of follow-up. In total, 75% patients had D'Amico intermediate- (48%) or high- (27%) risk PCa. Median follow-up was 5.6 yr. Median time to prostate-specific antigen (PSA) nadir was 3.3 mo, and 70 patients reached PSA <0.2ng/ml postcryoablation. The 90-d high-grade (Clavien Grade IIIa) complication rate was 3%, with no rectal fistulas reported. Continence and potency rates were 96% and 11%, respectively. The 5-yr biochemical failure-free survival (PSA nadir+2ng/ml) was 81% overall and 89% for low-, 78% for intermediate-, and 80% for high-risk PCa (p=0.46). The median follow-up was 5.6 and 5.1 yr for patients without biochemical failure and with biochemical failure, respectively. The 5-yr clinical recurrence-free survival was 83% overall and 94% for low-, 84% for intermediate-, and 69% for high-risk PCa (p=0.046). Failure to reach PSA nadir <0.2ng/ml within 6 mo postcryoablation was an independent predictor for biochemical failure (p=0.006) and clinical recurrence (p=0.03). The 5-yr metastases-free survival was 95%. Main limitation is retrospective evaluation. Primary whole-gland cryoablation for PCa provides acceptable medium-term oncologic outcomes and could be an alternative for radiation therapy or radical prostatectomy. PATIENT SUMMARY: Cryoablation is a safe, minimally-invasive procedure that uses cold temperatures delivered via probes through the skin to kill prostate cancer (PCa) cells. Whole-gland cryoablation may offer an alternative treatment option to surgery and radiotherapy. We found that patients had good cancer outcomes 5 yr after whole-gland cryoablation, and those with a prostate-specific antigen value ≥0.2ng/ml within 6 mo after treatment were more likely to have PCa recurrence.

Focal therapy in localised prostate cancer: Real-world urological perspective explored in a cross-sectional European survey

INTRODUCTION

The urological community's opinion over focal therapy (FT) for prostate cancer (PCa) has never been assessed. Our aim was to investigate the current opinion on FT in the European urological community.

METHODS

A 25-item questionnaire was devised according to the Cherries checklist and distributed through SurveyMonkey using a web link from November 2016 to October 2017. After a pilot validation (n = 40 urologists), the survey was sent through EAU and 9 other national European urological societies mailing list. Twitter was also used.

RESULTS

We received 484 replies from 51 countries. Almost half (44.8%, n = 217) stated FT would represent a step forward, and 52.0% (n = 252) would suggest FT to a patient. Almost three-quarters (70.8%, n = 343) agreed FT will become a standard option after improvements in patient selection (n = 66) or when its effectiveness will be proven (n = 78), or both (n = 199). Most frequently used definition of FT was treatment of all significant (life-threatening) cancer foci whilst leaving untreated the rest of the gland (39.3%, n = 190). FT use was considered as an alternative to whole-gland treatments by 29.7% (n = 144), and to AS by 25.0% (n = 121). On multivariate analysis, FT availability and publications were associated with a positive opinion on FT. Conversely, attending International congresses, treating high PCa volumes and high percentages of high-risk PCa was associated with a negative opinion.

CONCLUSIONS

FT is considered as an attractive option for PCa treatment by the European urological community sampled by our survey. FT availability positively influences these thoughts. The present survey suggests whilst some early adopters already embraced FT, the relative majority of the urological community is prone to embrace FT in the near future, once current areas of debate are solved.

Focal Treatment for Unilateral Prostate Cancer Using High-Intensity Focal Ultrasound: A Comprehensive Study of Pooled Data

BACKGROUND

Focal therapy for prostate cancer (PCa) remains experimental. Aim of the current study is to review available evidence and perform a pooled analysis exploring oncologic and functional results of high intensity focus ultrasound (HIFU) focal therapy for the treatment of unilateral PCa.

METHODS

The National Library of Medicine Database was searched for relevant articles. A wide search was performed, including the combination of following words: "HIFU," "prostate," "cancer," and "focal." Overall, 167 articles were reviewed. Of these, seven articles were identified and eligible for the pooled analysis. Data on HIFU hemiablation or focal prostate ablation, oncologic and functional results were pooled from these seven studies that included 366 men with unilateral PCa.

RESULTS

In the 366 analyzed cases, mean age was 67 years (95% confidence interval 66-69), and mean preoperative prostate-specific antigen was 6.4 ng/cc (5.5-7.4). Three studies included PCa up to Gleason 7 (3 + 4), three studies did include also Gleason 7 (4 + 3), whereas one study had no limitation in terms of Gleason score. Regarding early complications, low-grade Clavien-Dindo I-II were reported in 26% (16-37), whereas high-grade Clavien-Dindo ≥III were found in 3.8% (0-8.6). Analyzing oncologic outcomes mean follow-up was 26 months (23-31): at one year after HIFU, negative biopsy rate for clinically significant PCa was 87% (79-96), whereas salvage treatment-free survival rate was 92% (85-98). Regarding functional outcomes, reported potency rates were 74% (64-84), and continence 96% (91-100), although definitions of potency and continence were not homogenous across studies.

CONCLUSIONS

This pooled analysis of the results of focal HIFU treatment of PCa shows promising oncologic and functional outcomes. Well-selected patients may be candidates for such a conservative partial treatment of the gland. Well-designed trials are awaited to compare HIFU focal treatment with current standard of care.

Prediction of unilateral prostate cancer by the combination of transrectal ultrasonography-guided prostate biopsy and multi-parametric magnetic resonance imaging: A real-life experience

Hemi-ablation of prostate cancer (PCa) requires an accurate prediction of laterality. Recently, multi-parametric magnetic resonance imaging (mpMRI) has recently been increasingly used to enhance clinical staging and characterization of tumor foci. Thus, we tried to investigate the real-life accuracy of combinatory approach of using both transrectal ultrasound (TRUS)-guided prostatic biopsy and mpMRI in predicting the laterality of PCa. We reviewed the records of 335 men who were suspected of having unilateral PCa on multi (≥ 12)-core TRUS-guided biopsy and preoperative mpMRI and subsequently had undergone radical prostatectomy (RP) at our institution. Based on the analysis of pathologic outcomes from RP, the performance of the combinatory approach in predicting the pathological laterality of PCa was evaluated. Pathology was classified to be unfavorable when showing a Gleason pattern of 4/5 or pT3/N1 features. Significant cancer was defined as non-organ-confined disease, having a Gleason pattern of 4/5, or showing a cancer volume of ≥ 0.5 mL. Among the 335 unilateral lobes not suspected to harbor tumor from either the TRUS biopsy or mpMRI, the actual absence rate of malignancy was only 13.7% from a pathologic analysis of RP specimens. Even among the 115 D'Amico low-risk group, the absence rate of malignancy was only 26.1% in unilateral lobes not suspected to harbor tumor. Among the 335 lobes, unfavorable pathology and significant cancer were not observed in 36.1% and 30.7%, respectively. The absence rates of unfavorable pathology and significant cancer among the D'Amico low risk group were 56.5% and 47.8%, respectively. Meanwhile, the absence rate of dominant Gleason pattern 4 or 5 was 74.9% among the 335 total subjects. Our real-life clinical experience showed that the combination of multi-core TRUS-guided biopsy and mpMRI did not provide reliable accuracy in the prediction of true unilaterality of PCa.

Current status and progress of focal therapy in Asia

PURPOSE OF REVIEW

With the increasing incidence of low-to-intermediate risk of prostate cancer (PCa) by the introduction of prostate-specific antigen (PSA) screening, focal therapy has become one of the promising treatment options in the world. In Asia, same movement are occurring using several technologies including cryoablation, high-intensity focused ultrasound, brachytherapy and irreversible electroporation. However, these are still not common strategies to treat organ-confined PCa. The purpose of this review is to summarize the most updated experience and future direction of focal therapy in Asian countries.

RECENT FINDINGS

The prevalence and diagnosis of PCa are increasing in Asian countries. This increase is related to various factors including the widespread implementation of PSA testing and lifestyle changes to more Westernized diets. With the increasing detection rate of early stage PCa, overdetection and overtreatment are recognized even in Asia. In this setting, accumulating data on multiparametric MRI and MRI-targeted biopsy as well as MRI-transrectal ultrasound (TRUS) fusion biopsy suggest the potential in improving the detection of clinically significant PCa in Asia. Furthermore, targeted focal therapy has emerged as a promising treatment strategy aiming for both providing oncological outcome and maintaining functional preservation in many Asian countries.

SUMMARY

At present, focal therapy is not a current standard choice for the treatment of localized PCa in Asian countries. However, with the increase of localized PCa and patient's preference for less invasive treatment with preservation of organ-function, focal therapy should become a definite treatment option for localized PCa in Asia.

Urological technology: where will we be in 20 years' time?

Since prehistoric times, our understanding of urology has rapidly expanded. Whilst primitive urologists began by using urine as a therapeutic substance, modern urologists may find themselves removing a kidney remotely by driving a robotic arm, with seven degrees of movement, while using image overlay-augmented reality. This review provides an insight into the potential status of urological technology in 20 years' time, assessed through an analysis of developments in imaging, diagnostics, robotics and further technologies. A particular emphasis is given to the promising fields of minimally invasive techniques, nanotechnology and tissue engineering, which likely hold the key to a new era for urology.

Does Any Racial Disparity Exist in Oncologic Outcomes After Primary Cryotherapy for Prostate Cancer? A Matched-pair Comparative Analysis of the Cryo On-Line Data Registry

BACKGROUND

African-American (AA) men have the greatest incidence of and disease-specific mortality from prostate cancer of any racial group. Although encouraging oncologic and functional outcomes have been reported with prostate cancer cryotherapy, little is known about how ethnicity can potentially affect the oncologic outcomes of primary cryotherapy. We report the oncologic outcomes of primary cryotherapy in AA patients through a matched-pair analysis.

PATIENTS AND METHODS

A 1:2 (AA to non-AA) cohort of patients was designed using the Cryo-On-Line Data Registry. The 2 arms were matched for patient age, prostate-specific antigen level, Gleason score, and prostate volume. The oncologic outcome was defined in terms of the biochemical recurrence (BCR) rates after primary cryoablation using Phoenix criteria. The results of "for-cause" post-treatment biopsies and the BCR-free survival rates were also analyzed between the 2 groups.

RESULTS

The 1:2 cohort of AA and non-AA men in the present study included 109 and 218 men, respectively. Their median age (69 vs. 71 years; P = .71), median prostate-specific antigen level (6.5 vs. 6.8 ng/mL; P = .95), median prostate volume (32 vs. 30 cm³; P = .31), Gleason score distribution (P = .97), and prostate cancer risk group (P = .12) were similar statistically. The median postoperative follow-up period was also comparable between the 2 groups (AA, 32 months vs. non-AA, 27 months; P = .52). The BCR rates were similar between the AA and non-AA men (14% vs. 17%; P = .52). Likewise, the rate of positive "for-cause" prostate biopsy findings was similar between the 2 groups (AA vs. non-AA, 25% vs. 36%; P = .44). Furthermore, the 5-year biochemical relapse-free survival rates were comparable for the AA and non-AA patients (74% vs. 71%; P = .37).

CONCLUSION

When matched for tumor characteristics, cryotherapy as a treatment modality for primary, clinically localized prostate cancer offers men of African-American descent similar oncologic outcomes to those of non-AA men.

Cryotherapy versus high-intensity focused ultrasound for treating prostate cancer: Oncological and functional results

CONTEXT AND OBJECTIVE

The increasingly early diagnosis of prostate cancer requires a search for therapeutic alternatives with good oncological results that in turn facilitate a good long-term quality of life. This review analyses 2 minimally invasive therapies for treating localised prostate cancer in terms of oncological and functional results, as well as the complications resulting from the therapies.

ACQUISITION OF EVIDENCE

A systematic literature review was conducted of the treatment of localised prostate cancer with 2 ablative techniques as the primary therapy: cryosurgery or cryotherapy and high intensity focused ultrasound (HIFU). We included patients who underwent procedures that included the entire gland, with hemiablation or focal therapy, which were indicated for low to intermediate-risk prostate cancer according to the D'Amico criteria. We excluded patients with high-risk prostate cancer and those who underwent any prior treatment for prostate cancer.

SYNTHESIS OF THE EVIDENCE

After conducting the literature search and excluding the studies that did not meet the protocol criteria, we reviewed a total of 14 studies, with a total of 350 patients treated using cryotherapy and 1107 treated with HIFU. All studies were either prospective or retrospective and were not randomised. The patients' mean age was younger than 75 years. Overall, the rate of disease recurrence in the patients treated with cryotherapy varied between 13.2% and 26%, while the rate for those treated with HIFU varied between 7.3% and 67.9%. The overall demonstrated continence at 12 months was 97.6-100% for cryotherapy and 96-100% for HIFU. In terms of sexual potency rates, cryotherapy showed complete potency at 12 months for 86-100% of the patients treated with focal cryotherapy and slightly lower rates for hemiablation (76.9-100%) and total therapy (39%). HIFU showed potency rates of 89%, 52-80% and 33-78% for focal therapy, hemiablation and total therapy, respectively.

CONCLUSIONS

Both techniques have comparable functional results, although the somewhat poorer oncological results for HIFU reflect a steeper learning curve, which could lead to its use in centres with high volumes of patients.