Focal high-intensity focused ultrasound therapy for localized prostate cancer: An interim analysis of the multinational FASST study.

BACKGROUND: High-intensity focused ultrasound (HIFU) emerged as a novel approach for the treatment of localized prostate cancer (PCa). However, prospective studies on HIFU-related outcomes and predictors of treatment failure (TF) remain scarce. MATERIALS AND METHODS: We conducted a multinational prospective cohort study among patients undergoing HIFU therapy for localized, low- to intermediate-risk PCa. Follow-up data on serial prostate specific antigen (PSA), multi-parametric magnetic resonance imaging (mpMRI), targeted/systematic biopsies, adverse events and functional outcomes were collected. The primary endpoint was TF, defined as histologically confirmed PCa requiring whole-gland salvage treatment. Uni- and multi-variable adjusted hazard ratios (HRs) were calculated using Cox proportional hazard regression models. RESULTS: At baseline, mean (standard deviation) age was 64.14 (7.19) years, with the majority of patients showing T-stage 1 (73.9%) and International Society of Urological Pathology grading system Grade 2 (58.8%). PSA nadir (median, 1.70 ng/mL) was reached after 6 months. Of all patients recruited, 16% had clinically significant PCa, as confirmed by biopsy, of which 13.4% had TF. Notably, T-stage and number of positive cores at initial biopsy were independent predictors of TF during follow-up (HR [95% CI] 1.27 [1.02-1.59] and 5.02 [1.80-14.03], respectively). Adverse events were minimal (17% and 8% early and late adverse events, respectively), with stable or improved functional outcomes in the majority of patients. CONCLUSIONS: This interim analysis of a multinational study on HIFU therapy for the management of low-to-intermediate-risk PCa reveals good functional outcomes, minimal adverse events and low incidence of TF over the short-term. Data on long-term outcomes, specifically as it relates to oncological outcomes, are awaited eagerly.

Prostate-specific membrane antigen positron emission tomography in addition to multiparametric magnetic resonance imaging and biopsies to select prostate cancer patients for focal therapy.

OBJECTIVE: To evaluate the additional value of prostate-specific membrane antigen positron emission tomography (PSMA-PET) to conventional diagnostic tools to select patients for hemi-ablative focal therapy (FT). PATIENTS AND METHODS: We performed a retrospective analysis on a multicentre cohort (private and institutional) of 138 patients who underwent multiparametric magnetic resonance imaging (mpMRI), PSMA-PET, and systematic biopsies prior to radical prostatectomy between January 2011 and July 2021. Patients were eligible when they met the consensus criteria for FT: PSA <15 ng/mL, clinical/radiological T stage ≤T2b, and International Society of Urological Pathology (ISUP) grade 2-3. Clinically significant prostate cancer (csPCa) was defined as ISUP grade ≥2, extracapsular extension >0.5 mm or seminal vesicle involvement at final histopathology. The diagnostic accuracy of mpMRI, systematic biopsies and PSMA-PET for csPCa (separate and combined) was calculated within a four-quadrant prostate model by receiver-operating characteristic and 2 × 2 contingency analysis. Additionally, we assessed whether the diagnostic tools correctly identified patients suitable for hemi-ablative FT. RESULTS: In total 552 prostate quadrants were analysed and 272 (49%) contained csPCa on final histopathology. The area under the curve, sensitivity, specificity, positive predictive value and negative predictive value for csPCa were 0.79, 75%, 83%, 81% and 77%, respectively, for combined mpMRI and systematic biopsies, and improved after addition of PSMA-PET to 0.84, 87%, 80%, 81% and 86%, respectively (P < 0.001). On final histopathology 46/138 patients (33%) were not suitable for hemi-ablative FT. Addition of PSMA-PET correctly identified 26/46 (57%) non-suitable patients and resulted in 4/138 (3%) false-positive exclusions. CONCLUSIONS: Addition of PSMA-PET to the conventional work-up by mpMRI and systematic biopsies could improve selection for hemi-ablative FT and guide exclusion of patients for whom whole-gland treatments might be a more suitable treatment option.

Focal therapy with high-intensity focused ultrasound for prostate cancer: 3-year outcomes from a prospective trial.

OBJECTIVE: To assess the oncological and functional outcomes of focal high-intensity focused ultrasound (HIFU) in treating localised prostate cancer (PCa), a 3-year prospective study was undertaken using periodic post-ablation saturation biopsies. PATIENTS AND METHODS: Men with two or fewer lesions of grade group (GG) ≤3 PCa were eligible for participation. Additional criteria included a prostate-specific antigen (PSA) level of ≤15 ng/mL, clinical T1c-T2, and a life expectancy of ≥10 years. The primary endpoint was failure-free survival (FFS), defined as absence of clinically significant PCa (csPCa) in- or out-of-field on protocol-mandated saturation biopsy, no whole-gland or systemic salvage treatment, PCa metastasis, or PCa-related death. Results are reported using two distinct definitions of csPCa: (i) the presence of any GG ≥2 and (ii) any GG ≥3 or core involvement of ≥6 mm. Secondary endpoints were functional patient-reported outcome measures addressing urinary, sexual, and bowel function. RESULTS: A total of 91 patients were included: six (7%) with GG1 and 85 (93%) with GG ≥2. In all, 83 (91%) underwent at least one follow-up biopsy. Biopsy attendance at 6, 12, and 36 months was 84%, 67%, and 51%, respectively. The FFS at these time points for any GG ≥2 PCa was 79% (95% confidence interval [CI] 80-88%), 57% (95% CI 48-69%) and 44% (95% CI 34-56%), respectively. Using the second definition, FFS were 88% (95% CI 81-95%), 70% (95% CI 61-81%) and 65% (95% CI 55-77%), respectively. The 3-year cancer-specific survival was 100%, and freedom from metastasis was 99%. Magnetic resonance imaging (MRI) (negative predictive value of up to 89%, 95% CI 84-93%) and relative decrease of PSA values (P = 0.4) performed poorly in detecting residual disease. Urinary and bowel assessment returned to baseline questionnaire scores within 3 months. In all, 17 (21%) patients reported meaningful worsening in erectile function. A significant decrease of PCa related anxiety was observed. CONCLUSIONS: Focal HIFU treatment for localised PCa shows excellent functional outcomes with half of the patients remaining cancer-free after 3 years. Whole-gland treatment was avoided in 81%. Early follow-up biopsies are crucial to change or continue the treatment modality at the right time, while the use of MRI and PSA in detecting PCa recurrence is uncertain.

Irreversible electroporation of localised prostate cancer downregulates immune suppression and induces systemic anti-tumour T-cell activation - IRE-IMMUNO study.

OBJECTIVES: To prospectively compare systemic anti-tumour immune responses induced by irreversible electroporation (IRE) and robot-assisted radical prostatectomy (RARP) in patients with localised intermediate-risk prostate cancer (PCa). PATIENTS AND METHODS: Between February 2021 and June 2022, before and after treatment (at 5, 14 and 30 days) peripheral blood samples of 30 patients with localised PCa were prospectively collected. Patient inclusion criteria were: International Society of Urological Pathologists Grade 2-3, clinical cancer stage ≤T2c, prostate-specific antigen level <20 ng/mL). Patients were treated with IRE (n = 20) or RARP (n = 10). Frequency and activation status of lymphocytic and myeloid immune cell subsets were determined using flow cytometry. PCa-specific T-cell responses to prostatic acid phosphatase (PSAP) and cancer testis antigen (New York oesophageal squamous cell carcinoma 1 [NY-ESO-1]) were determined by interferon-γ enzyme-linked immunospot assay (ELISpot). Repeated-measures analysis of variance and two-sided Student's t-tests were used to compare immune responses over time and between treatment cohorts. RESULTS: Patient and tumour characteristics were similar between the cohorts except for age (median 68 years [IRE] and 62 years [RARP], P = 0.01). IRE induced depletion of systemic regulatory T cells (P = 0.0001) and a simultaneous increase in activated cytotoxic T-lymphocyte antigen 4 (CTLA-4)+ cluster of differentiation (CD)4+ (P < 0.001) and CD8+ (P = 0.032) T cells, consistent with reduction of systemic immune suppression allowing for effector T-cell activation, peaking 14 days after IRE. Effects were positively correlated with tumour volume/ablation size. Accordingly, IRE induced expansion of PSAP and/or NY-ESO-1 specific T-cell responses in four of the eight immune competent patients. Temporarily increased activated myeloid derived suppressor cell frequencies (P = 0.047) were consistent with transient immunosuppression after RARP. CONCLUSIONS: Irreversible electroporation induces a PCa-specific systemic immune response in patients with localised PCa, aiding conversion of the tumour microenvironment into a more immune permissive state. Therapeutic efficacy might be further enhanced by combination with CTLA-4 checkpoint inhibition, potentially opening up a new synergistic treatment paradigm for high-risk localised or (oligo)metastatic disease.

Targeted microwave ablation for prostate cancer (FOSTINE1b): a prospective 'ablate-and-resect' study.

OBJECTIVE: To assess histopathological outcomes, as well as feasibility and safety of targeted microwave ablation (TMA) via the Trinity® system (KOELIS, La Tronche, France). PATIENTS AND METHODS: Prospective, single-institution, interventional Phase IIa study with an 'ablate-and-resect' design. In all, 11 patients diagnosed with localised prostate cancer (PCa) underwent TMA via the Trinity system under conscious sedation in an outpatient setting using a single transrectal TATO® 18-G antenna with different treatment regimens. Magnetic resonance imaging (MRI) and robot-assisted radical prostatectomy (RARP) were conducted at 7 days and 1 month after TMA, respectively. Nine patients received RARP, and two patients chose to withdraw their consent following TMA. These men chose an active surveillance protocol upon confirmation of a low-risk prostate cancer diagnosis. Functional outcomes and adverse events were evaluated at baseline and follow-up visits using validated questionnaires. Prostate volumetry and confirmation of necrosis were carried out through MRI and whole-mount histopathological examination. RESULTS: The TMA was successfully executed, and all patients were discharged on the same day. No severe adverse events (Common Terminology Criteria for Adverse Events Grade ≥3) were reported at the 7-day and 1-month follow-up visits. Additionally, no declines were observed in urinary, sexual and ejaculation functional outcomes. T1-weighted MRI revealed clear and well-defined ablation zones. The RARP was executed without difficulty, particularly during the dissection of the posterior plane. As a result, no intraoperative complications were encountered. Histopathological assessment on surgical specimens confirmed the absence of viable cells, indicating complete necrosis of the ablative zone if a power intensity >10 W was used during TMA. Ablation zone volumetry revealed no notable distinctions between the three-dimensional segmentation of the virtual ablation zone at TMA (median volume: 2 mL) and MRI (median volume: 1.923 mL). Conversely, a significant reduction was noted in the surgical specimen (median volume: 0.221 mL). CONCLUSIONS: Targeted microwave ablation via the Trinity system for localised PCa treatment proves to be a secure and feasible procedure, with complete necrosis evidence within the ablation zone on surgical specimens.

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.

Follow-up of vascular-targeted photodynamic therapy in a real-world setting.

PURPOSE: Vascular-targeted photodynamic therapy (VTP) is an approved treatment option for unilateral low-risk prostate cancer (PCa). METHODS: Patients with unilateral low- or intermediate-risk PCa undergoing hemiablation by VTP were evaluated in a real-world setting. Oncological outcome after VTP was measured by MRI-based re-biopsy at 12 and 24 months. Functional outcome after 1 year was investigated by IIEF-5 and IPSS questionnaires. Progression was defined as the evidence3 of ISUP ≥ 2 PCa. RESULTS: At any control biopsy (n = 46) after VTP, only 37% of patients showed no evidence of PCa. Recurrence-free survival was 20 months (95% CI 4.9-45.5) and progression-free survival was 38.5 months (95% CI 33.5-43.6 months). In-field and out-field recurrent PCa occurs in 37% (55% ISUP ≥ 2 PCa) and 35% (56% ISUP ≥ 2 PCa). Seventy-nine percent of patients preserved erectile function, respectively. Ten percent of patients presented long-term bladder outlet obstruction. None of the patients presented incontinence. CONCLUSION: Due to the high-recurrence in- and out-field recurrence rate in a mainly low-risk prostate cancer cohort, VTP has to be regarded critically as a therapy option in these patients. Pre-interventional diagnostic evaluation is the main issue before focal therapy to reduce the risk of tumor recurrence and progression.

Prospective close monitoring of the effect of vascular-targeted photodynamic therapy and high intensity focused ultrasound of localized prostate cancer by multiparametric magnetic resonance imaging.

PURPOSE: The aim of this study is to describe the anatomical and functional changes observed in multiparametric magnetic resonance imaging (mpMRI) during follow-up after focal therapy (FT) for localized prostate cancer (PCa). MATERIALS AND METHODS: In this prospective study, we analyzed pre- and postoperatively acquired mpMRI of 10 patients after FT (7 days; 3, 6, 9, 12 months). 7/10 (70%) patients underwent vascular-targeted photodynamic therapy (VTP). 3/10 (30%) patients underwent high-intensity focused ultrasound (HIFU). MpMR image analysis was performed using a semi-automatic software for segmentation of the prostate gland (PG) and tumor zones. Signal intensities (SI) of T2-weighted (T2w), T1-weighted (T1w),diffusion-weighted (DWI) and dynamic contrast-enhanced (DCE) images as well as volumes of the prostate gland (PGV) and tumor volumes (TV) were evaluated at each time point. RESULTS: The results showed a significant increase of PGV 7 days after FT (p = 0.042) and a significant reduction of PGV between 7 days and 6, 9 and 12 months after FT (p < 0.001). The TV increased significantly 7 days after FT (p < 0.001) and decreased significantly between 7 days and 12 months after FT (p < 0.001). There was a significant increase in SI of the ADC in the ablation zone after 6, 9 and 12 months after FT (p < 0.001). 1/9 patients (11%) had recurrent tumor on rebiopsy characterized as a a small focal lesion on mpMRI with strong diffusion restriction (low SI on ADC map and high SI on b-value DWI). CONCLUSION: MpMRI is able to represent morphologic changes of the ablated zone after FT and might be helpful to detect recurrent tumor.

Radiation therapy and IRreversible electroporation for intermediate risk prostate cancer (RTIRE).

INTRODUCTION: Radiation Therapy and IRreversible Electroporation for Intermediate Risk Prostate Cancer (RTIRE) is a phase II clinical trial testing combination of radiation therapy and irreversible electroporation for intermediate risk prostate cancer BACKGROUND: PCa is the most common non-cutaneous cancer in men and the second leading cause of cancer death in men. PCa treatment is associated with long term side effects including urinary, sexual, and bowel dysfunction. Management of PCa is based on risk stratification to prevent its overtreatment and associated treatment-related toxicity. There is increasing interest in novel treatment strategies, such as focal therapy, to minimize treatment associated morbidity. Focal therapy alone has yet to be included in mainstream guidelines, given ongoing concerns with potentially higher risk of recurrence. We hypothesize combining focal therapy with whole gland, reduced dose radiotherapy will provide acceptable oncologic efficacy with minimal treatment associated morbidity. RTIRE is a phase II single institution, investigator-initiated study combining a local ablative technique though local irreversible electroporation (IRE) with MR guided RT (MRgRT) to treat the entire prostate. The goal is to provide excellent oncologic outcomes and minimize treatment related side effects through leveraging benefits of locally ablative therapy with established radiation treatment techniques. METHODS: A total of 42 men with intermediate risk PCa per NCCN guidelines and focal grade group (GG) 2 or 3, Gleason Score (GS) 3 + 4 or GS 4 + 3, cancer in an MRI target will be enrolled. Patients with MRI visible foci of GG2/GG3 will undergo focal therapy with IRE of this lesion. Following successful focal therapy, patients will then undergo a course of reduced dose, whole gland MRgRT with either 32.5 Gy in 5 Fractions or 22 Gy in 2 fractions. The primary objective of the study is to determine safety. Secondary outcomes include evaluation of oncologic efficacy (as measured by the proportion of patients free of clinically significant cancer as defined as > Grade Group 1 at 1-year follow-up biopsy), imaging characteristics of patients pre and post RTIRE, impact on quality of life (QoL), and PSA kinetics. DISCUSSION: Combining IRE with a reduced dose radiotherapy may offer a new treatment paradigm for PCa by both reducing treatment effects of full dose radiotherapy and minimizing the risk of recurrence observed with focal therapy. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05345444. Date of registration: April 25, 2022. PROTOCOL VERSION: 6.0, July 7, 2023.

Focal Therapy in Grade Group 3 Prostate Cancer.

PURPOSE OF THIS REVIEW: Treatment of intermediate risk prostate cancer remains controversial. Clearly some patients with low volume favorable intermediate risk can be followed with active surveillance. Those with high volume bilateral disease need more radical whole gland therapy. The question remains on how to best treat low volume localized unfavorable intermediate risk prostate cancer (GG3) while maintaining quality of life. Focal therapy has been becoming a popular option for many patients with localized prostate cancer. Most studies looking at focal therapy for prostate cancer have been limited to GG1 and GG2, many of whom may not need treatment. We set out to review the literature evaluating the safety and efficacy of focal therapy for GG3 prostate cancer. RECENT FINDINGS: We reviewed multiple peer review articles obtained from a PubMed search. While in field biopsy recurrence rates approach 20%, failure free survival and overall survival exceeds 90%. While focal therapy for unfavorable GG3 intermediate risk prostate cancer may have higher rates of local recurrence with appropriate post procedure follow up, patients who need salvage therapy are easily identified and survival rates are very high. Focal therapy is a good option for patients with localized low volume GG3 prostate cancer without compromising cancer survival and preserving quality of life.

Novel image-guided marker aimed at organ-preserving therapies for prostate cancer.

OBJECTIVE: We developed fiducial imaging-guidance markers for the prostate with less imaging artifacts than currently commercially available markers. The aim of this study was to evaluate the imaging artifacts and potential usefulness and safety of these novel fiducial imaging markers in preclinical experiments. METHODS: We selected specific metal materials and a shape that can minimize artifacts in line with a license we obtained for a metal with a gold-platinum (Au-Pt) alloy composition that maximized artifact-free MRI images. Both phantom and canine prostate tests were conducted in order to evaluate the imaging artifacts for three imaging modalities, MRI, CT and ultrasound, and the risk of migration of the markers from the site of insertion to elsewhere, as well as crushing. RESULTS: The newly developed Au-Pt material had less imaging artifacts in the MRI, CT and ultrasound imaging modalities in comparison with current commercially available fiducial markers made from gold materials only. The Au-Pt markers had sufficient strength and durability and were considered to be potentially clinically useful and safe markers. CONCLUSION: The developed Au-Pt markers could be potential tools for accurate lesion-targeted, organ-preserving therapies such as lesion-targeted focal therapy and active surveillance in addition to conventional radiation therapies.

External validation of biochemical recurrence definition to predict oncologic outcomes following focal therapy for localized prostate cancer using high intensity focused ultrasound.

PURPOSE: This is an external validation of several biochemical recurrence definitions based on prostate specific antigen criteria (PSA). The purpose is to predict the need of additional treatment and failure after focal therapy using high intensity focused ultrasound (HIFU) for localized prostate cancer (PCa). MATERIALS AND METHODS: A total of 343 consecutive patients who underwent HIFU with Ablatherm® and Focal One® devices between June 2001 and November 2020 were identified. Treatment failure was defined as clinically significant PCa on postoperative biopsy, the need for salvage radical or systematic treatment, metastasis, or PCa-related death. The biochemical recurrence definitions tested were PSA nadir, time to PSA nadir, percentage of PSA reduction, Huber et al. criteria defined as PSA nadir + 1 ng/mL at 12 months or PSA nadir + 1.5 ng/mL at 24-36 months. Multivariable Cox regression analysis and decision-curve analysis were used to validate and compare criteria. Kaplan-Meier analysis was used to assess criteria associated with the highest accuracy. RESULTS: One hundred seventy-eight patients met the inclusion criteria and were analyzed. Overall, 61 (34%) and 41 (23%) patients had an additional treatment and failure with a median follow-up of 52 months. At multivariable analysis, model including Huber et al. criteria exhibited the highest Harrell's C-index for the prediction of the need of additional treatment (hazard ratio [HR]: 10, p < 0.001, c-index: 84%) and treatment failure (HR: 9.1, p < 0.001, c-index: 82%) as well as higher net benefit. The 60-months need of additional treatment and treatment failure-free survival were 89% and 98% compared to 26% and 49%, respectively, when stratified according to Huber et al. criteria (Log-rank test, p < 0.001). Similar results were found after excluding patient with non-clinically significant PCa at initial biopsy. CONCLUSIONS: We report an external validation of biochemical recurrence definitions predicting the need of additional treatment and failure after focal therapy using HIFU for localized PCa. Huber et al. criteria were identified as the most accurate and could be used to guide clinicians toward further evaluation and salvage treatments.

Patient-reported functional outcomes and oncological control after primary focal cryotherapy for clinically significant prostate cancer: A Phase II mandatory biopsy-monitored study.

INTRODUCTION: We report herein the impact of focal therapy (FT) on multi-domain functional outcomes in a Phase II prospective clinical trial (NCT04138914) in focal cryotherapy for clinically significant prostate cancer (csPCa). METHODS: The primary outcome was the detection of a ≥5 point deterioration in any of the four main expanded prostate index composite (EPIC) functional domains. Pretreatment multiparametric magnetic resonance imaging (mpMRI) and transperineal targeted and systematic saturation biopsy were used to select patients with prostate-specific antigen (PSA)≤20 ng/mL, Gleason grade group (GG) ≤4, mpMRI lesion volume ≤ 3 mL (for a single lesion) or ≤1.5 mL (where two lesions were present). Focal cryotherapy was performed with a minimum 5 mm margin around each target lesion. EPIC scores were obtained at baseline and posttreatment at 1, 3, 6, and 12 months. Mandatory repeat mpMRI and prostate biopsy were performed at 12 months to determine the infield and outfield recurrence. RESULTS: Twenty-eight patients were recruited. The mean age was 68 years, with PSA of 7.3 ng/mL and PSA density of 0.19 ng/mL2 . No Clavien-Dindo ≥3 complications occurred. Transient worsening of EPIC urinary (mean diff 16.0, p < 0.001, 95% confidence interval [CI]: 8.8-23.6) and sexual function scores (mean diff 11.0, p:0.005, 95% CI: 4.0-17.7) were observed at 1-month posttreatment, with recovery by Month 3. A subgroup who had ablation extending to the neurovascular bundle had a trend to delayed recovery of sexual function to Month 6. At 12-month repeat mpMRI and biopsy, 22 patients (78.6%) had no detectable csPCa. Of the six patients (21.4%) who had csPCa recurrences, four were GG2, one GG3, and one GG4. Four patients underwent repeat FT, one underwent radical prostatectomy, while the remaining one patient with low-volume GG2 cancer opted for active surveillance. CONCLUSION: FT using cryotherapy was associated with a transient deterioration of urinary and sexual function with resolution at 3 months posttreatment and with reasonable early efficacy in well-selected csPCa patients.

Combination of DNA methylation biomarkers with multiparametric magnetic resonance and ultrasound imaging fusion biopsy to detect the local spread of prostate cancer.

BACKGROUND: This study aimed to investigate the extent of field cancerization adjacent to index lesions in prostate cancer (PCa) by measuring DNA methylation of selected tumor suppressor genes in the perifocal tissue of PCa not visible on multiparametric magnetic resonanse imaging (mpMRI) for the safe zone of focal therapy identification. METHODS: A total of 272 patients were enrolled in this study, 44 patients' tissue biosamples were included in the field cancerization research, and 272 urine samples were included in the urine-based test development. Targeted biopsies were performed using the mpMRI/ultrasoundimage fusion system. RESULTS: Quantitative analysis revealed significantly higher DNA methylation levels of RARB, RASSF1, GSTP1 & APC genes in the index lesion compared with perifocal tissue samples 10 mm away from it (p < 0.0001). Notably, the RARB, GSTP1 & APC and RARB, RASSF1, GSTP1 & APC biomarker combinations exhibited the highest sensitivity and specificity comparing the extent of DNA methylation in index lesions and noncancerous prostate tissues 20 mm away (both area under the curve [AUC] = 0.98; p < 0.0001). The analysis of the potential urinary biomarkers showed that the combination of all four DNA methylation biomarkers with prostate-specific antigen (PSA) or PSA density (PSAD) in the blood significantly improves the detection of clinically significant PCa (csPCa). The combination of the four-biomarker test with PSAD allowed the identification of csPCa with ≥90% sensitivity and specificity. CONCLUSION: Thus, this study suggests that for focal therapy by region target hemi-ablation, the safe distance from the index lesion is no less than 10 mm. Noninvasive urine DNA methylation tests in combination with PSAD could be used for further follow-up of the patients, but larger prospective studies with external validation are needed.

Guidelines of guidelines: focal therapy for prostate cancer, is it time for consensus?

OBJECTIVE: To provide a summary and discussion of international guidelines, position statements and consensus statements in relation to focal therapy (FT) for prostate cancer (PCa). METHODS: The European Association of Urology-European Association of Nuclear Medicine-European Society for Radiotherapy and Oncology-European Society of Urogential Radiology-International Society of Urological Pathology-International Society of Geriatric Oncology and American Urological Association-American Society for Radiation Oncology-Society of Urologic Oncology guidelines were interrogated for recommendations for FT. PubMed and Ovid Medline were searched for consensus statements. Only studies in English since 2015 were included. Reference lists of the included articles were also interrogated and a manual search for studies was also performed. RESULTS: Our results showed a lack of long-term randomised data for FT. International Urological guidelines emphasised the need for more high-quality clinical trials with robust oncological and toxicity outcomes. Consensus and positions statements were heterogenous. CONCLUSION: A globally accepted guideline for FT planning, technique and follow-up are still yet to be determined. Well-designed studies with long-term follow-up and robust clinical and toxicity endpoints are needed to improve our understanding of FT and create uniform guidelines to streamline management and follow-up.

Median 4-year outcomes of salvage irreversible electroporation for localized radio-recurrent prostate cancer.

OBJECTIVES: To evaluate the safety, and short to mid-term oncological and quality-of-life (QoL) outcomes of focal irreversible electroporation (IRE) for radio-recurrent prostate cancer (PCa) at a median follow-up of 4 years. PATIENTS AND METHODS: This was a single-centre series of men with biopsy-proven radio-recurrent PCa treated with IRE between December 2013 and February 2022, with a minimum follow-up of 6 months. Follow-up included magnetic resonance imaging at 6 months, and standard transperineal saturation template biopsies at 12 months. Further biopsies were guided by suspicion on serial imaging or prostate-specific antigen (PSA) levels. Validated questionnaires were used to measure functional outcomes. Significant local recurrence was defined as any International Society of Urological Pathology (ISUP) score ≥ 2 on biopsies. Progression-free survival was defined as no signs of local or systemic disease on either imaging or template biopsies, or according to the Phoenix criteria for biochemical recurrence. RESULTS: Final analysis was performed on 74 men with radio-recurrent PCa (median age 69 years, median PSA level 5.4 ng/mL, 76% ISUP score 2/3). The median (range) follow-up was 48 (27-68) months. One rectal fistula occurred, and eight patients developed urethral sloughing that resolved with transurethral resection. Among patients who returned questionnaires (30/74, 41%), 93% (28/30) had preserved urinary continence and 23% (7/30) had sustained erectile function at 12-month follow-up. Local control was achieved in 57 patients (77%), who needed no further treatment. Biopsy diagnosed 41(55%) patients received follow up template biopsies, in-field recurrences occurred in 7% (3/41), and out-field recurrences occurred in 15% of patients (6/41). The metastasis-free survival rate was 91% (67/74), with a median (interquartile range) time to metastases of 8 (5-27) months. The Kaplan-Meier estimated 5-year progression-free survival rate was 60%. CONCLUSIONS: These short- to mid-term safety, oncological and QoL outcome data endorse results from smaller series and show the ability of salvage focal IRE to safely achieve oncological control in patients with radio-recurrent PCa.

Salvage irreversible electroporation for radio-recurrent prostate cancer - the prospective FIRE trial.

OBJECTIVES: To prospectively assess the safety, functional- and oncological-outcomes of irreversible electroporation (IRE) as salvage therapy for radio-recurrent focal prostate cancer in a multicenter setting. PATIENTS AND METHODS: Men with focal recurrent PCa after external beam radiation or brachytherapy without metastatic disease on staging imaging and co-registration between mpMRI and biopsies were prospectively included in this multicenter trial. Adverse events were reported following the Clavien-Dindo classification. Validated questionnaires were used for patient-reported functional outcomes. Follow-up consisted of 3 monthly prostate specific antigen (PSA) levels, a 6-month mpMRI and standardised transperineal template mapping biopsies at 12-months. Thereafter follow-up was guided by MRI and/or PSMA-PET/CT and PSA. Local recurrence was defined as any ISUP score ≥2 on biopsies. RESULTS: 37 patients were analysed with a median (interquartile range (IQR)) follow up of 29 (22-43) months. Median age was 71 (53-83), median PSA was 3.5 ng/mL (2.7-6.1). 28 (75.5%) patients harboured intermediate risk and 9 patients (24.5%) high risk PCa. Seven patients (19%) reported self-limiting urgency, frequency, or hematuria (grade 1-2). Seven patients (19%) developed a grade 3 AE; urethral sludge requiring transurethral resection. At 12 months post treatment 93% of patients remained continent and erectile function sufficient for intercourse deteriorated from 35% to 15% (4/27). Local control was achieved in 29 patients (78%) and 27 patients (73%) were clear of local and systemic disease. Four (11%) patients had local recurrence only. Six (16%) patients developed metastatic disease with a median time to metastasis of 8 months. CONCLUSION: The FIRE trial shows that salvage IRE after failed radiation therapy for localised PCa is safe with minimal toxicity, and promising functional and oncological outcomes. Salvage IRE can offer a possible solution for notoriously difficult to manage radio recurrent prostate tumours.

Prostate cancer outcomes following whole-gland and focal high-intensity focused ultrasound.

OBJECTIVE: To report the 5-year failure-free survival (FFS) following high-intensity focused ultrasound (HIFU). PATIENTS AND METHODS: This observational cohort study used linked National Cancer Registry data, radiotherapy data, administrative hospital data and mortality records of 1381 men treated with HIFU for clinically localised prostate cancer in England. The primary outcome, FFS, was defined as freedom from local salvage treatment and cancer-specific mortality. Secondary outcomes were freedom from repeat HIFU, prostate cancer-specific survival (CSS) and overall survival (OS). Cox regression was used to determine whether baseline characteristics, including age, treatment year, T stage and International Society of Urological Pathology (ISUP) Grade Group were associated with FFS. RESULTS: The median (interquartile range [IQR]) follow-up was 37 (20-62) months. The median (IQR) age was 65 (59-70) years and 81% had an ISUP Grade Group of 1-2. The FFS was 96.5% (95% confidence interval [CI] 95.4%-97.4%) at 1 year, 86.0% (95% CI 83.7%-87.9%) at 3 years and 77.5% (95% CI 74.4%-80.3%) at 5 years. The 5-year FFS for ISUP Grade Groups 1-5 was 82.9%, 76.6%, 72.2%, 52.3% and 30.8%, respectively (P < 0.001). Freedom from repeat HIFU was 79.1% (95% CI 75.7%-82.1%), CSS was 98.8% (95% CI 97.7%-99.4%) and OS was 95.9% (95% CI 94.2%-97.1%) at 5 years. CONCLUSION: Four in five men were free from local salvage treatment at 5 years but treatment failure varied significantly according to ISUP Grade Group. Patients should be appropriately informed with respect to salvage radical treatment following HIFU.

Median 5-year outcomes of primary focal irreversible electroporation for localised prostate cancer.

OBJECTIVES: To evaluate longer-term oncological and functional outcomes of focal irreversible electroporation (IRE) as primary treatment for localised clinically significant prostate cancer (csPCa) at a median follow-up of 5 years (up to 10 years). PATIENTS AND METHODS: All patients that underwent focal IRE as primary treatment for localised PCa between February 2013 and August 2021 with a minimum 12 months of follow-up were analysed. Follow-up included 6-month magnetic resonance imaging (MRI) and standardised transperineal saturation template ± targeted biopsies at 12 months, and further biopsies in the case of clinical suspicion on serial imaging and/or prostate-specific antigen (PSA) levels. Failure-free survival (FFS) was defined as no progression to radical treatment or nodal/distant disease. Local recurrence was defined as any International Society of Urological Pathology Grade of ≥2 on biopsy. RESULTS: A total of 229 patients were analysed with a median (interquartile range [IQR]) follow-up of 60 (40-80) months. The median (IQR) age was 68 (64-74) years, the median (IQR) PSA level was 5.9 (4.1-8.2) ng/mL, and 86% harboured intermediate-risk disease and 7% high-risk disease. In all, 38 patients progressed to radical treatment (17%), at a median (IQR) of 35 (17-53) months after IRE. Kaplan-Meier FFS rates were 91% at 3 years, 84% at 5 years and 69% at 8 years. Metastasis-free survival was 99.6% (228/229), PCa-specific and overall survival were 100% (229/229). Residual csPCa was found in 24% (45/190) during follow-up biopsy and MRI showed a complete ablation in 82% (186/226). Short-term urinary continence was preserved (98%, three of 144 at baseline, 99%, one of 131 at 12 months) and erections sufficient for intercourse decreased by 13% compared to baseline (71% to 58%). CONCLUSION: Longer-term follow-up confirms our earlier findings that focal IRE provides acceptable local and distant oncological control in selected men with less urinary and sexual toxicity than radical treatment. Long-term follow-up and external validation of these findings, is required to establish this new treatment paradigm as a valid treatment option.

External validation of a risk model predicting failure of salvage focal ablation for prostate cancer.

OBJECTIVES: To externally validate a published model predicting failure within 2 years after salvage focal ablation in men with localised radiorecurrent prostate cancer using a prospective, UK multicentre dataset. PATIENTS AND METHODS: Patients with biopsy-confirmed ≤T3bN0M0 cancer after previous external beam radiotherapy or brachytherapy were included from the FOcal RECurrent Assessment and Salvage Treatment (FORECAST) trial (NCT01883128; 2014-2018; six centres), and from the high-intensity focussed ultrasound (HIFU) Evaluation and Assessment of Treatment (HEAT) and International Cryotherapy Evaluation (ICE) UK-based registries (2006-2022; nine centres). Eligible patients underwent either salvage focal HIFU or cryotherapy, with the choice based predominantly on anatomical factors. Per the original multivariable Cox regression model, the predicted outcome was a composite failure outcome. Model performance was assessed at 2 years post-salvage with discrimination (concordance index [C-index]), calibration (calibration curve and slope), and decision curve analysis. For the latter, two clinically-reasonable risk threshold ranges of 0.14-0.52 and 0.26-0.36 were considered, corresponding to previously published pooled 2-year recurrence-free survival rates for salvage local treatments. RESULTS: A total of 168 patients were included, of whom 84/168 (50%) experienced the primary outcome in all follow-ups, and 72/168 (43%) within 2 years. The C-index was 0.65 (95% confidence interval 0.58-0.71). On graphical inspection, there was close agreement between predicted and observed failure. The calibration slope was 1.01. In decision curve analysis, there was incremental net benefit vs a 'treat all' strategy at risk thresholds of ≥0.23. The net benefit was therefore higher across the majority of the 0.14-0.52 risk threshold range, and all of the 0.26-0.36 range. CONCLUSION: In external validation using prospective, multicentre data, this model demonstrated modest discrimination but good calibration and clinical utility for predicting failure of salvage focal ablation within 2 years. This model could be reasonably used to improve selection of appropriate treatment candidates for salvage focal ablation, and its use should be considered when discussing salvage options with patients. Further validation in larger, international cohorts with longer follow-up is recommended.