Therapeutic prostate cancer interventions: quantification of pubic arch interference and needle positioning errors.

INTRODUCTION: This study focuses on the quantification of and current guidelines on the hazards related to needle positioning in prostate cancer treatment: (1) access restrictions to the prostate gland by the pubic arch, so-called Pubic Arch Interference (PAI) and (2) needle positioning errors. Next, we propose solution strategies to mitigate these hazards. METHODS: The literature search was executed in the Embase, Medline ALL, Web of Science Core Collection*, and Cochrane Central Register of Controlled Trials databases. RESULTS: The literature search resulted in 50 included articles. PAI was reported in patients with various prostate volumes. The level of reported PAI varied between 0 and 22.3 mm, depending on the patient's position and the measuring method. Low-Dose-Rate Brachytherapy induced the largest reported misplacement errors, especially in the cranio-caudal direction (up to 10 mm) and the largest displacement errors were reported for High-Dose-Rate Brachytherapy in the cranio-caudal direction (up to 47 mm), generally increasing over time. CONCLUSIONS: Current clinical guidelines related to prostate volume, needle positioning accuracy, and maximum allowable PAI are ambiguous, and compliance in the clinical setting differs between institutions. Solutions, such as steerable needles, assist in mitigating the hazards and potentially allow the physician to proceed with the procedure.This systematic review was performed in accordance with the PRISMA guidelines. The review was registered at Protocols.io (DOI: dx.doi.org/10.17504/protocols.io.6qpvr89eplmk/v1).

Robotic-assisted laparoscopic radical prostatectomy for treatment of a newly identified lesion revealed no viable cells in the previously treated area with microwave focal therapy.

Introduction: Histological outcome of the targeted focal therapy is in principle confirmed by targeted needle biopsy from the treated area in clinical trial. Herein, we report a rare case in which the MFT was followed by RARP. Case presentation: A 68-year-old man with PSA 9.6 ng/mL and PI-RADS 4 lesion in the right transition zone on multi-parametric MRI underwent MR/ultrasound fusion-guided targeted biopsy, which revealed grade-group 1 cancer. Targeted focal therapy with microwave ablation was performed, resulting in disappearance of the PI-RADS 4 lesion at post-operative 4 months. However, PSA rose to 11.5 ng/mL, and a new PI-RADS 4 lesion, was identified in the left peripheral zone. RARP was performed to reveal new grade-group 3 cancer, and no viable cells in the previously treated area with MFT. Conclusion: RARP was safely performed even after MFT and proved the pathological complete response of microwave ablation.

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.

A Description and Safety Overview of Irreversible Electroporation for Prostate Tissue Ablation in Intermediate-Risk Prostate Cancer Patients: Preliminary Results from the PRESERVE Trial.

The PRESERVE study (NCT04972097) aims to evaluate the safety and effectiveness of the NanoKnife System to ablate prostate tissue in patients with intermediate-risk prostate cancer (PCa). The NanoKnife uses irreversible electroporation (IRE) to deliver high-voltage electrical pulses to change the permeability of cell membranes, leading to cell death. A total of 121 subjects with organ-confined PCa ≤ T2c, prostate-specific antigens (PSAs) ≤ 15 ng/mL, and a Gleason score of 3 + 4 or 4 + 3 underwent focal ablation of the index lesion. The primary endpoints included negative in-field biopsy and adverse event incidence, type, and severity through 12 months. At the time of analysis, the trial had completed accrual with preliminary follow-up available. Demographics, disease characteristics, procedural details, PSA responses, and adverse events (AEs) are presented. The median (IQR) age at screening was 67.0 (61.0-72.0) years and Gleason distribution 3 + 4 (80.2%) and 4 + 3 (19.8%). At 6 months, all patients with available data (n = 74) experienced a median (IQR) percent reduction in PSA of 67.6% (52.3-82.2%). Only ten subjects (8.3%) experienced a Grade 3 adverse event; five were procedure-related. No Grade ≥ 4 AEs were reported. This study supports prior findings that IRE prostate ablation with the NanoKnife System can be performed safely. Final results are required to fully assess oncological, functional, and safety outcomes.

Bibliometric analysis of focal therapy in prostate cancer research.

Introduction: The use of focal therapies for prostate cancer (PCa) has soared, as it controls disease and is associated with minimal side effects. Bibliometric analysis examines the global research landscape on any topic to identify gaps in the research and areas for improvement and prioritize future research efforts. This study aims to examine the research outputs and trends and collaboration landscape in the field of focal therapy for PCa on a global scale. Methods: We searched Medline, PubMed and Scopus for peer-reviewed publications on our research topic using controlled keywords. Search results were limited to the period between 1980 and 2022, screened for duplicates and then included in our study based on prespecified eligibility criteria. The Bibliometrix Package was used for comprehensive science mapping analysis of co-authorship, co-citation and co-occurrence analysis of countries, institutions, authors, references and keywords in this field. Results: This analysis included 2578 research articles. The annual scientific production increased from one article in 1982 to 143 in 2022 (13.21%). The average citation per year was incrementally increasing, and these documents were cited around 32.52 times. The documents included in this analysis were published in 633 sources. The international collaboration index was 22.7. In total, 6280 author keywords were identified. The most used keywords were 'prostate cancer', 'focal therapy', 'prostate' and 'photodynamic therapy'. Conclusion: This bibliometric analysis has provided a comprehensive review of focal therapy in PCa research, highlighting both the significant growth in the field and the existing gaps that require further exploration. The study points to the need for more diverse international collaboration and exploration of various treatment modalities within the context of focal therapy.

Combined holmium laser enucleation of the prostate with high-intensity focused ultrasound in treating patients with localized prostate cancer in a prostate with volume > 60 g: Oncological and functional outcomes from single-institution study.

OBJECTIVE: To assess the efficacy and safety of combined High-Intensity Focused Ultrasound (HIFU) and Holmium Laser Enucleation of the Prostate (HoLEP) in treating patients with both localized prostate cancer (PCa) and prostate > 60 g. METHODS: All patients who underwent HIFU for treatment of localized PCa were prospectively enrolled in our study. We reviewed records of patients undergoing procedures from January 2016 to January 2023. For patients with prostate sizes > 60 g, HoLEP was offered before HIFU to prevent worsened urinary symptoms post-treatment. Oncological outcomes-prostatic-specific (PSA) kinetics, recurrence rates, treatment failure - and functional results-Sexual Health Inventory for Men (SHIM), International Prostate Symptoms Score (IPSS), and urinary complications were compared between patients undergoing combined HoLEP and HIFU with those underwent HIFU-monotherapy. RESULTS: Among 100 patients, 74 underwent HIFU-monotherapy and 26 underwent the combined HoLEP and HIFU. The majority had intermediate-risk PCa (67%). Pathologic assessment of HoLEP specimens showed no tumor evidence in 57% of cases. In comparison to the HIFU-only group, the combined group exhibited significantly lower PSA metrics across various intervals, however, no differences were found regarding overall and infield recurrences and treatment failure rates. While the combined treatment initially resulted in higher incontinence rates and shorter catheterization durations (P < 0.001), no significant difference in IPSS was observed during subsequent follow-ups. CONCLUSION: HoLEP and HIFU can be safely combined for the treatment of PCa in patients with >60 g prostate volume without compromising early oncological outcomes thereby expanding the therapeutic scope of HIFU in treating patients with localized PCa and large adenomas.

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.

MRI-based monitoring of prostate cancer after HIFU: Inter-reader agreement and diagnostic performance of the PI-FAB score.

PURPOSE: To investigate inter-reader agreement, and diagnostic performance of the Prostate Imaging after Focal Ablation (PI-FAB) score applied to multiparametric MRI (mpMRI) in patients who underwent focal high-intensity focused ultrasound (HIFU) therapy for localized prostate cancer. METHODS: In this retrospective, IRB-approved, single-center study, 73 men, who underwent focal HIFU treatment and received follow-up mpMRIs with subsequent prostate biopsies, were included. The PI-FAB score was applied to follow-up MRIs at 6, 12, and 36 months post-HIFU by two radiologists with different experience levels. Inter-reader agreement was assessed using Gwet's AC1, and the diagnostic performance of the PI-FAB score was assessed in relation to histopathologic results of subsequent prostate biopsies for each reader. RESULTS: PI-FAB scores showed substantial to almost perfect inter-reader agreement (AC1: 0.80-0.95) and demonstrated high specificity (Reader 1: 90-98 %, Reader 2: 87-98 %) and NPVs (Reader 1: 91-100 %, Reader 2: 88-97 %) in ruling out residual or recurrent in-field prostate cancer post-HIFU. Sensitivity (Reader 1: ≥43 %, Reader 2: ≥14 %) and PPVs (Reader 1: ≥33 %, Reader 2: ≥14 %) were mostly relatively lower, with notable disparities between the two readers, indicating the potential influence of radiologist experience. CONCLUSIONS: The PI-FAB score provides a consistent and reliable tool for post-HIFU monitoring of prostate cancer using mpMRI. It demonstrates substantial to almost perfect inter-reader agreement and is particularly effective in excluding in-field residual or recurrent prostate cancer post-HIFU treatment. Its application can potentially enhance post-treatment patient care, emphasizing its value as a non-invasive MRI-based monitoring approach after focal ablative therapy of the prostate.

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.

Evaluating Diagnostic Accuracy and Inter-reader Agreement of the Prostate Imaging After Focal Ablation Scoring System.

Background and objective: Focal therapy (FT) is increasingly recognized as a promising approach for managing localized prostate cancer (PCa), notably reducing treatment-related morbidities. However, post-treatment anatomical changes present significant challenges for surveillance using current imaging techniques. This study aimed to evaluate the inter-reader agreement and efficacy of the Prostate Imaging after Focal Ablation (PI-FAB) scoring system in detecting clinically significant prostate cancer (csPCa) on post-FT multiparametric magnetic resonance imaging (mpMRI). Methods: A retrospective cohort study was conducted involving patients who underwent primary FT for localized csPCa between 2013 and 2023, followed by post-FT mpMRI and a prostate biopsy. Two expert genitourinary radiologists retrospectively evaluated post-FT mpMRI using PI-FAB. The key measures included inter-reader agreement of PI-FAB scores, assessed by quadratic weighted Cohen's kappa (κ), and the system's efficacy in predicting in-field recurrence of csPCa, with a PI-FAB score cutoff of 3. Additional diagnostic metrics including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy were also evaluated. Key findings and limitations: Scans from 38 patients were analyzed, revealing a moderate level of agreement in PI-FAB scoring (κ = 0.56). Both radiologists achieved sensitivity of 93% in detecting csPCa, although specificity, PPVs, NPVs, and accuracy varied. Conclusions and clinical implications: The PI-FAB scoring system exhibited high sensitivity with moderate inter-reader agreement in detecting in-field recurrence of csPCa. Despite promising results, its low specificity and PPV necessitate further refinement. These findings underscore the need for larger studies to validate the clinical utility of PI-FAB, potentially aiding in standardizing post-treatment surveillance. Patient summary: Focal therapy has emerged as a promising approach for managing localized prostate cancer, but limitations in current imaging techniques present significant challenges for post-treatment surveillance. The Prostate Imaging after Focal Ablation (PI-FAB) scoring system showed high sensitivity for detecting in-field recurrence of clinically significant prostate cancer. However, its low specificity and positive predictive value necessitate further refinement. Larger, more comprehensive studies are needed to fully validate its clinical utility.

The Transatlantic Recommendations for Prostate Gland Evaluation with Magnetic Resonance Imaging After Focal Therapy (TARGET): A Systematic Review and International Consensus Recommendations.

BACKGROUND AND OBJECTIVE: Magnetic resonance imaging (MRI) can detect recurrences after focal therapy for prostate cancer but there is no robust guidance regarding its use. Our objective was to produce consensus recommendations on MRI acquisition, interpretation, and reporting after focal therapy. METHODS: A systematic review was performed in July 2022 to develop consensus statements. A two-round consensus exercise was then performed, with a consensus meeting in January 2023, during which 329 statements were scored by 23 panellists from Europe and North America spanning urology, radiology, and pathology with experience across eight focal therapy modalities. Using RAND Corporation/University of California-Los Angeles methodology, the Transatlantic Recommendations for Prostate Gland Evaluation with MRI after Focal Therapy (TARGET) were based on consensus for statements scored with agreement or disagreement. KEY FINDINGS AND LIMITATIONS: In total, 73 studies were included in the review. All 20 studies (100%) reporting suspicious imaging features cited focal contrast enhancement as suspicious for cancer recurrence. Of 31 studies reporting MRI assessment criteria, the Prostate Imaging-Reporting and Data System (PI-RADS) score was the scheme used most often (20 studies; 65%), followed by a 5-point Likert score (six studies; 19%). For the consensus exercise, consensus for statements scored with agreement or disagreement increased from 227 of 295 statements (76.9%) in round one to 270 of 329 statements (82.1%) in round two. Key recommendations include performing routine MRI at 12 mo using a multiparametric protocol compliant with PI-RADS version 2.1 standards. PI-RADS category scores for assessing recurrence within the ablation zone should be avoided. An alternative 5-point scoring system is presented that includes a major dynamic contrast enhancement (DCE) sequence and joint minor diffusion-weighted imaging and T2-weighted sequences. For the DCE sequence, focal nodular strong early enhancement was the most suspicious imaging finding. A structured minimum reporting data set and minimum reporting standards for studies detailing MRI data after focal therapy are presented. CONCLUSIONS AND CLINICAL IMPLICATIONS: The TARGET consensus recommendations may improve MRI acquisition, interpretation, and reporting after focal therapy for prostate cancer and provide minimum standards for study reporting. PATIENT SUMMARY: Magnetic resonance imaging (MRI) scans can detect recurrent of prostate cancer after focal treatments, but there is a lack of guidance on MRI use for this purpose. We report new expert recommendations that may improve practice.

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.

Focal Minimally Invasive Treatment in Localized Prostate Cancer: Comprehensive Review of Different Possible Strategies.

BACKGROUND: Focal therapy is a promising, minimally invasive method for the treatment of patients with localized prostate cancer. According to the existing literature, there is growing evidence for positive functional outcomes and oncological effectiveness. The aim of this review is to evaluate the technical efficacy of three minimally invasive techniques (cryoablation, electroporation, and microwave ablation) and their impact on quality of life in patients with prostate cancer. METHODS: Studies between January 2020 and July 2023 were selected using PubMed, Embase, and The Cochrane Library and analyzed following PRISMA guidelines; they have not been registered. RESULTS: Twenty-three studies investigating three different sources of energy to deliver focal therapy were found. Thirteen studies evaluated the performance of the cryoablation therapy, seven studies of the irreversible electroporation, and three studies of microwave ablation option. The majority of studies were retrospective cohort studies. Cryoablation showed excellent oncological outcomes for low-grade prostate cancer, whether performed on the lesion, on the hemigland, or on the entire gland, with the best results obtained for patients with intermediate risk. Irreversible electroporation showed promising oncological outcomes with no significant changes in functional outcomes. Microwave ablation showed great early functional outcomes. CONCLUSIONS: The oncological effectiveness of minimally invasive treatment in comparison to standard of care is still under investigation, despite encouraging results in terms of functional outcomes improvement and adverse events reduction. More comprehensive research is needed to fully understand the function of minimally invasive treatment in patients with localized PCa.

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.

Magnetic resonance imaging-ultrasound fusion guided focal cryoablation for men with intermediate-risk prostate cancer.

INTRODUCTION: Focal therapy (FT) is a form of ablative treatment offered to men with localized, organ-confined prostate cancer (CaP). Pelvic multiparametric magnetic resonance imaging (mpMRI) and mpMRI/transrectal ultrasound fusion (MRI-US) guidance enable the precise delivery of FT with limited ablation of adjacent benign tissue or vital genitourinary structures. This article presents our findings on using MRI-US to perform FT as a primary treatment for men with intermediate-risk CaP. METHODS: Thirty-six men underwent MRI-US fusion-guided FT cryoablation at a single center from 2018 to 2023 as a primary treatment for intermediate-risk CaP. Following FT, quarterly prostate-specific antigen (PSA) testing and a 6 to 9 month mpMRI and combined MRI-US targeted and systematic biopsy were performed. Oncological outcomes were determined using several endpoints containing biochemical recurrence, imaging failure, and pathological failure. Functional outcomes were measured using reported erectile dysfunction/potency rates, urinary incontinence rates, and the American Urologic Association Symptom Score (AUA-SS) and Sexual Health Inventory for Men (SHIM) indices. RESULTS: Median follow-up was 29.1 months, most (75%) of whom had grade group 2 CaP. Out of the 36 men, 32 (88.9%) completed the combined MRI-targeted and systematic biopsy follow-up after treatment. The study had no major complications, but 12 (33.3%) patients experienced Clavien-Dindo grade II or lower complications. For oncological outcomes, 6 (16.7%) men had biochemical recurrence, 9 (25%) showed imaging failure, and 8 (22.2%) met the criteria for positive biopsy- out-of-field vs. in-field. 88.2% of previously potent patients remained potent postoperatively at 12 months. All patients were continent at 12 months. There were no statistically significant changes in the AUA-SS and SHIM scores postoperatively. CONCLUSION: MRI-US-guided cryoablation to target lesions in intermediate-risk CaP appears to be a safe treatment option, with functional outcomes indicating minimal short and intermediate-term morbidity and acceptable oncological outcomes. However, despite close monitoring and follow-up, there is still a limitation in accurately predicting/detecting pathological failure after FT. The long-term durability of FT for intermediate-risk, organ-confined CaP remains uncertain.

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.

Adaptation of a Clinical High-Frequency Transrectal Ultrasound System for Prostate Photoacoustic Imaging: Implementation and Pre-clinical Demonstration.

OBJECTIVE: High-frequency, high-resolution transrectal micro-ultrasound (micro-US: ≥15 MHz) imaging of the prostate is emerging as a beneficial tool for scoring disease risk and accurately targeting biopsies. Adding photoacoustic (PA) imaging to visualize abnormal vascularization and accumulation of contrast agents in tumors has potential for guiding focal therapies. In this work, we describe a new imaging platform that combines a transrectal micro-US system with transurethral light delivery for PA imaging. METHODS: A clinical transrectal micro-US system was adapted to acquire PA images synchronous to a tunable laser pulse. A transurethral side-firing optical fiber was developed for light delivery. A polyvinyl chloride (PVC)-plastisol phantom was developed and characterized to image PA contrast agents in wall-less channels. After resolution measurement in water, PA imaging was demonstrated in phantom channels with dyes and biodegradable nanoparticle contrast agents called porphysomes. In vivo imaging of a tumor model was performed, with porphysomes administered intravenously. RESULTS: Photoacoustic imaging data were acquired at 5 Hz, and image reconstruction was performed offline. PA image resolution at a 14-mm depth was 74 and 261 µm in the axial and lateral directions, respectively. The speed of sound in PVC-plastisol was 1383 m/s, and the attenuation was 4 dB/mm at 20 MHz. PA signal from porphysomes was spectrally unmixed from blood signals in the tumor, and a signal increase was observed 3 h after porphysome injection. CONCLUSION: A combined transrectal micro-US and PA imaging system was developed and characterized, and in vivo imaging demonstrated. High-resolution PA imaging may provide valuable additional information for diagnostic and therapeutic applications in the prostate.

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.