MRI-guided Transurethral Ultrasound Ablation Research Articles

Evolution of non-perfused volume after transurethral ultrasound ablation of prostate: A retrospective 12-month analysis

BackgroundA detailed understanding of the non-perfused volume (NPV) evolution after prostate ablation therapy is lacking. The impact of different diseased prostate tissues on NPV evolution post-ablation is unknown. PurposeTo characterize the NPV evolution for three treatment groups undergoing heat-based prostate ablation therapy, including benign prostatic hyperplasia (BPH), primary prostate cancer (PCa), and radiorecurrent PCa. Materials and methodsStudy design and data analysis were performed retrospectively. All patients received MRI-guided transurethral ultrasound ablation (TULSA). 21 BPH, 28 radiorecurrent PCa and 40 primary PCa patients were included. Using the T1-weighted contrast-enhanced MR image, the NPV was manually contoured by an experienced radiologist. All patients received an MRI immediately following the ablation. Follow-up included MRI at 3- and 12 months for BPH and radiorecurrent PCa patients and at 6- and 12 months for primary PCa patients. ResultsA significant difference between BPH and radiorecurrent PCa patients was observed at three months (p < 0.0001, Wilcoxon rank sum test), with the median NPV decreasing by 77 % for BPH patients but increasing by 4 % for radiorecurrent PCa patients. At six months, the median NPV decreased by 97 % for primary PCa. Across all groups, although 40 % of patients had residual NPV at 12 months, it tended to be < 1 mL. ConclusionThe resolution of necrotic tissue after ablation was markedly slower for irradiated than treatment-naïve prostate tissue. These results may account for the increased toxicity observed after radiorecurrent salvage therapy. By 12 months, most necrotic prostate tissue had disappeared in every treatment group.

Durability of Functional Outcomes After MRI-Guided Transurethral Ultrasound Ablation of the Prostate

Long-term data on functional outcomes after MRI-guided transurethral ultrasound ablation (TULSA) are limited. We assess the 5-year post-TULSA durability of outcomes for patient-reported genitourinary function, bowel function, and adverse events in 30 patients with primary, localized prostate cancer treated with TULSA across 3 centers. Patients received a conservative treatment plan in a phase 1 study designed to assess safety and feasibility. Follow-up visits took place at 1, 3, 6, 12 months, and biannually up to 5 years. Median (interquartile range) age at baseline was 69 (67-71) years. Erectile dysfunction (International Index of Erectile Function [IIEF] ≤17) was prevalent at baseline, with a mean (95% confidence interval [CI]) score of 16 (12-19), decreasing to 9 (4-14) at 5 years. At the 5-year visit, 71% of men who attempted intercourse in the recall period reported preservation of IIEF Q2 ≥2 erections sufficient for penetration. The mean (95% CI) International Prostate Symptom Score (IPSS) decreased from 9.0 (7.0-11) to 7.1 (5.0-9.1) from baseline to 5 years; IPSS-quality of life, maximum urinary flow rate, and post-void residual urine were stable or improved. Maintenance of bowel function and urinary continence was 100%. There was no new attributable serious or severe adverse event from 1 to 5 years. With a durably favorable safety profile, TULSA has the potential to treat cancer conservatively while simultaneously alleviating lower urinary tract symptoms. Data from larger studies are pending.

MP73-09 A RETROSPECTIVE CLINICAL SERVICE EVALUATION OF LESION-TARGETED MRI-GUIDED TRANSURETHRAL ULTRASOUND ABLATION (TULSA) FOR THE TREATMENT OF LOCALIZED PROSTATE CANCER

You have accessJournal of UrologyCME1 Apr 2023MP73-09 A RETROSPECTIVE CLINICAL SERVICE EVALUATION OF LESION-TARGETED MRI-GUIDED TRANSURETHRAL ULTRASOUND ABLATION (TULSA) FOR THE TREATMENT OF LOCALIZED PROSTATE CANCER Rolf Muschter, Leonhard Steinmeister, and Agron Lumiani Rolf MuschterRolf Muschter More articles by this author , Leonhard SteinmeisterLeonhard Steinmeister More articles by this author , and Agron LumianiAgron Lumiani More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003341.09AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: MR-guided transurethral ultrasound ablation (TULSA) is a novel minimally-invasive therapy option for the treatment of organ-confined prostate cancer (PCa) through a whole-gland or lesion-targeted approach. TULSA has shown promising safety and oncological outcomes with minimum side-effect on patients urinary, bowel, and sexual functions. The objective of this retrospective single-center study was to perform a clinical service evaluation of lesion-targeted TULSA for patients with localized PCa. METHODS: Men with organ-confined PCa (proved by MRI and biopsy) received lesion-targeted TULSA with sparing of sphincter, urethra, and rectum. A customized treatment was planned for every patient based on his expectations and PCa characteristics. For a subset of men with concurrent PCa and benign prostate hyperplasia (BPH), TULSA was applied as a combined therapy. Repeat TULSA was allowed and a suprapubic catheter was used. The Clavien-Dindo stratification was used to assess the frequency and severity of all adverse events (AEs). Mid-term oncological outcomes were evaluated using multi-parametric MRI (mpMRI) and prostate-specific antigen (PSA). Surgeon-assessed functional outcomes were recorded. RESULTS: 180 patients (150 primary and 30 salvage) with median [IQR] age, baseline PSA, and follow-up availability of 67 [63-76], 8.0 ng/ml [5.2-13], and 12-mon (max 48), respectively, were treated. 40 patients experienced Grade 1 and 2 AEs, resolving within 4 weeks using antibiotics or relevant medication. Grade 3 AEs (urinary retention requiring surgical intervention) occurred in two patients, resolving within 3 months. No grade 4 or higher events and no bowel-related complications occurred. 98% of men preserved pad-free continence. 94/94 men, who were previously potent, maintained erectile potency. 85% of men with concurrent BPH and PCa experienced symptom relief. The mid-term oncological success rate was 88%. A single repeat TULSA was performed on 13 patients. CONCLUSIONS: Lesion-targeted TULSA is a safe and customizable prostate ablation therapy with promising mid-term oncological outcomes and minimal side-effect profile on patients erectile, bowel, and urinary functions. TULSA offers the flexibility to treat localized prostate cancer in a primary, salvage, or concurrent setting of BPH through a patient-tailored whole-gland or lesion-targeted approach. Source of Funding: No funding was received © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1038 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Rolf Muschter More articles by this author Leonhard Steinmeister More articles by this author Agron Lumiani More articles by this author Expand All Advertisement PDF downloadLoading ...

Abstract No. 160 MR Susceptibility-Weighted Imaging During Transurethral Prostate Sono-Ablation Procedures for Guidance of Device Placement to Counter Effect of Intra-Prostatic Calcifications

Men seeking MRI-guided transurethral ultrasound ablation (TULSA) for treatment of prostate cancer (PCa) are screened for calcifications. Large calcifications can block ultrasound (US) and cause inadequate heating. Smaller calcifications (≤3 mm) can be accommodated by aligning the ultrasound applicator (UA) with calcifications between transducer elements. We compare calcification detection and size measurement using susceptibility-weighted MRI (SWI) vs. computed tomography (CT). We also assess the impact of calcifications on ablation coverage benchmarked against a previously published pivotal trial. Pre-TULSA screening for calcifications (calcs) was performed with CT for 17 men. The mean (range) of CT slice thickness was 1.6 (0.6-5.0) mm. When relevant calcs were detected, intraprocedural SWI (1.0-mm slices) was used to guide positioning of UA elements with respect to calcs. Calcification in-plane and through-plane diameters were measured on CT and SWI, and their impact on ablation coverage was assessed using MR thermometry. Maximum temperature and thermal dose maps from MR thermometry were segmented in 90-degree quadrants across the active UA elements, with presence of calcification assessed based on SWI magnitude and phase images. 25 prostatic calcs were identified across 17 men. All calcs identified on CT were visible on SWI. In 4 men, SWI phase images were used to differentiate calcs from iron. Mean (range) diameter was 3.8 (1.4-10.4) mm on CT and 4.0 (2.2-10.8) mm using SWI. SWI diameters were larger by median 22% in at least one dimension for all men and in 42/50 measurements overall. With SWI-guided UA placement in 9 men, median (IQR) proportion of target volume reaching boiling temperature was 4.0 (2-8.0) % and 3.0 (0-7.0) % in sectors with and without calcs based on MR thermometry. Adequate thermal dose was achieved in men with and without calcs: 98 (93-100) % vs 98 (95-100) %. In the pivotal trial of 115 patients, which did not have SWI-guided UA placement, 93% (90-98%) of quadrants with calcs reached adequate thermal coverage compared with 98 (93-100)% overall and 6 (1-9)% with calcs had target volume approaching boiling vs 0 (0-5) % overall. Intraprocedural SWI detected all CT-identified calcifications, tending to overestimate the diameter but guiding effective device positioning. CT remains the gold standard for pre-TULSA calcification screening, and further studies are warranted to optimize SWI protocols, correlate the size of calcifications on CT and SWI, and predict their impact on ablation coverage.

Four-year follow-up of MRI-guided Transurethral Ultrasound Ablation (TULSA) in men with localized prostate cancer

Four-year follow-up of MRI-guided Transurethral Ultrasound Ablation (TULSA) in men with localized prostate cancer

Safety and efficacy of MRI-guided transurethral ultrasound ablation for radiorecurrent prostate cancer in the presence of gold fiducial markers.

Safety and efficacy of ultrasound prostate ablation for radiorecurrent prostate cancer (PCa) in the presence of gold fiducial markers has not been previously reported. To evaluate safety, functional, and early-stage oncological outcomes for patients with gold fiducial markers undergoing salvage magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (sTULSA) for radiorecurrent PCa. Data were acquired from an ethics-approved, single-center phase-1 study. Eight patients with 18 total gold fiducial markers inside the planned treatment volume were identified. MRI controls were performed at three and 12 months, followed by PSMA-PET-CT imaging and biopsies at 12 months. A control cohort of 13 patients who underwent sTULSA without markers were also identified for safety profile comparison. Adverse events were reported using the Clavien-Dindo classification, and questionnaires including EPIC-26, IPSS, and IIEF-5 were collected. Of 18 markers, 2 (11%) were directly responsible for poor ultrasound penetration. However, there were no local recurrences at 12 months. PSA, prostate volume, and non-perfused volume all decreased over time. At 12 months, 11/18 (61%) of fiducial markers had disappeared via sloughing. The adverse event profile was similar between both patient cohorts, and when controlled for ablation type, no statistical difference in functional outcomes between the two cohorts was observed. Patients with radiorecurrent PCa with intraprostatic gold fiducial markers can be successfully treated with TULSA. The early-stage efficacy of sTULSA for patients with intraprostatic gold markers is encouraging and the safety profile is unaffected by marker presence.

Abstract No. 112 Customized prostate ablation using MRI-guided transurethral ultrasound ablation (TULSA): initial experience at a private radiology practice

Abstract No. 112 Customized prostate ablation using MRI-guided transurethral ultrasound ablation (TULSA): initial experience at a private radiology practice

Abstract No. 111 ▪ FEATURED ABSTRACT Pivotal trial of MRI-guided transurethral ultrasound ablation in men with localized prostate cancer: three-year follow-up

MRI-guided transurethral ultrasound ablation (TULSA) of prostate tissue is a novel directional ultrasound heating under real-time MRI thermometry feedback control. We report 3-year outcomes from the pivotal TULSA-PRO Ablation Clinical Trial.

Magnetic Resonance Imaging-Guided Transurethral Ultrasound Ablation of Prostate Cancer: A Systematic Review.

Purpose:MRI-guided transurethral ultrasound ablation (TULSA) uses real-time MR thermometry feedback to target prostate disease. We systematically review the literature to synthesize efficacy, functional, and safety outcomes and assess the influence of planned ablation fraction on outcome.Materials and Methods:PubMed, Embase, and the Cochrane Library were searched from inception to June 2021 following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies reporting at least one efficacy, functional, or safety outcome after a single TULSA treatment were included. The relationship of freedom from salvage treatment and potency preservation with planned ablation volume was modeled.Results:Two hundred twenty-four patients were treated in 10 studies with up to a 5-year follow-up, mainly for primary localized prostate cancer (PCa) plus smaller cohorts with recurrent PCa, and locally advanced PCa (LAPC). The prostate-specific antigen decline from baseline up to 2 years, including focal to whole-gland ablation plans, was 54% to 97%. The rate of salvage treatment after one TULSA treatment for primary PCa was 7% to 17%. Continence and potency preservation were from 92% to 100% and from 75% to 98%. Urinary symptoms were stable in men with good voiding function at baseline, and 85% of men with concurrent PCa and lower urinary tract symptoms met the criteria for improvement. Symptom relief in a small cohort of men with LAPC was observed. Grade III adverse events were incurred by 13/224 men (6%), with no rectal injury/fistula or Grade IV complication. The planned ablation fraction was linearly related to salvage-free survival. The relationship between potency preservation and planned ablation fraction followed a sigmoid curve.Conclusions:As an alternative to conventional treatments, TULSA is safe and effective for prostate tissue ablation in men with primary PCa. There is also evidence that TULSA delivers effective relief of urinary symptoms while treating PCa in a single, low-morbidity procedure. The likelihood of freedom from additional treatment or potency preservation is associated with the planned ablation fraction.

The role for MRI-guided transurethral ultrasound ablation in the continuum of prostate cancer care.

Prostate cancer continues to have a negative impact on the duration and quality of life for males and their families. MRI is transforming the pathway of prostate cancer detection, diagnosis, staging, and surveillance, backed by multiple Level 1 studies and robust reporting standards. This evolving paradigm of MRI-directed care is now being expanded to include in-bore MRI-guided prostate tissue ablation techniques, which reduce the burden of genitourinary complications associated with standard-of-care treatments, without sacrificing cancer control. The workflow for MRI-guided transurethral ultrasound ablation relies on intraprocedural MRI guidance for treatment planning, automated and physician-monitored treatment delivery, and post-treatment assessment at both immediate and long-term time points. Our early experience has identified several procedure refinements, and aligns with early evidence from prospective clinical studies using transurethral ultrasound ablation for treatment of patients with either primary or recurrent disease. Driven by quantitative real-time imaging, MRI-guided ablative interventions provide rich datasets for developing technical refinements and predictive models that will progressively improve patient outcomes as these novel techniques become part of a new standard-of-care.

A0314 - MRI-guided transurethral ultrasound ablation for localized clinically significant prostate cancer: 12-month clinical outcomes of a phase 2 study

A0314 - MRI-guided transurethral ultrasound ablation for localized clinically significant prostate cancer: 12-month clinical outcomes of a phase 2 study

Single-Center Evaluation of Treatment Success Using Two Different Protocols for MRI-Guided Transurethral Ultrasound Ablation of Localized Prostate Cancer.

ObjectivesTo assess differences in 24-month oncologic and functional outcomes in men with low to intermediate-risk prostate cancer treated with MRI-guided transurethral ultrasound ablation (TULSA) using intentionally conservative versus intensified treatment parameters.Patients and MethodsPatients from a single center involved in two multicenter trials were included in this analysis. This included 14 of 30 patients with Gleason 3 + 3 from a Phase I study using intentionally conservative treatment parameters, and 15 of 115 patients with Gleason ≤ 3 + 4 from a pivotal study using intensified parameters. Follow-up data compared across these cohorts included 12-month biopsy and MRI for all patients, and 24-month PSA, micturition and quality of life (IIEF, IPSS, IPSS-QOL). The prognostic value of baseline parameters and PSA kinetics on 12-month histological recurrence was evaluated by logistic regression.Results12-month biopsy revealed clinically significant residual disease in 4 (29%) and 2 (14%) patients from the Phase I and pivotal studies, respectively. PSA nadir was 0.7 ng/ml for Phase I and 0.5 ng/ml for pivotal study patients. Patient age at diagnosis, use of MRI fusion/systematic prostate biopsy, number of obtained cores at initial biopsy, PSA course, and PSA nadir were identified as prognostic factors for treatment success. All but one patient from each cohort maintained erection firmness sufficient for penetration. No cases of pad use were reported at 24 months. There were no Grade 4 or higher adverse events, and no late toxicity related to the procedure.ConclusionTwo-year follow-up demonstrated the efficacy of TULSA for the treatment of localized prostate cancer, and the durability of PSA and functional outcomes. Intensifying treatment parameters in the pivotal trial had no impact on safety or functional outcomes through 24 months, while reducing the recurrence rate for clinically significant disease. Careful patient selection by MRI fusion/systematic prostate biopsy and adequate follow-up through routine 12-month biopsy are recommended.

P0047 - MRI-guided transurethral ultrasound ablation for treatment of benign prostatic obstruction

P0047 - MRI-guided transurethral ultrasound ablation for treatment of benign prostatic obstruction

Relief of Lower Urinary Tract Symptoms After MRI-Guided Transurethral Ultrasound Ablation for Localized Prostate Cancer: Subgroup Analyses in Patients with Concurrent Cancer and Benign Prostatic Hyperplasia.

Background: MRI-guided transurethral ultrasound ablation (TULSA) offers minimally invasive thermal ablation of benign and malignant prostate tissue, using directional high-intensity ultrasound and real-time, magnetic resonance thermometry feedback control. Feasibility of TULSA for alleviating lower urinary tract symptoms (LUTSs) associated with benign prostatic hyperplasia (BPH) is retrospectively assessed in a subgroup of men from a localized prostate cancer study who also had LUTSs. Patients and Methods: TULSA was used to ablate 90% of the prostate gland in 30 men with localized prostate cancer, without plans to spare ejaculatory ducts. Mean ± standard deviation treatment time was 37 ± 10 minutes. Retrospective analysis was conducted on a subpopulation of nine patients who also suffered from LUTSs (International Prostate Symptom Score [IPSS] ≥ 12 at baseline) as well as a smaller subgroup of five patients with IPSS >12 and peak urinary flow (Qmax) <15 mL/second. Urinary symptom relief, continence, and erectile function were assessed using IPSS, International Index of Erectile Function (IIEF), and uroflowmetry. Results: At 12 months post-TULSA, IPSS improved significantly by 58% to 6.3 ± 5.0 (p = 0.003), with at least a moderate (≥6 points) reduction in eight of nine patients. IPSS quality of life improved in eight of nine patients. Erectile function (IIEF-EF) remained stable from 14.6 ± 9.3 at baseline to 15.7 ± 9.0 at 12 months. The proportion of patients with erections sufficient for penetration (IIEF Q2 ≥2) was unchanged. Full urinary continence (pad free and leak free) was achieved at 12 months in all patients. In five men who suffered from more severe symptoms, Qmax increased from 11.6 ± 2.6 mL/second to 22.5 ± 14.2 mL/second at 12 months (p = 0.126). Perfused prostate volume, measured on MRI, decreased 70% to 13.6 ± 4.6 mL (p = 0.003) at 12 months. All adverse events were mild to moderate (Common Terminology Criteria for Adverse Events [CTCAE] Grade 1-2) with no serious events reported. Conclusions: This retrospective analysis demonstrates promising safety and feasibility of TULSA to relieve LUTSs, with improvement in IPSS comparable with modern, minimally invasive surgical therapies. Larger controlled studies with BPH-specific ablation plans in men seeking treatment for LUTSs are warranted.

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

The shift in the diagnostic algorithm for prostate cancer to early imaging with mpMRI has resulted in many patients being diagnosed with small volume, apparently unilateral, clinically significant cancers. In these patients, a minimally invasive, nonmorbid intervention is appealing. The aim of this study was to review data reported within the last 2 years on focal therapy and partial gland ablation for organ-confined prostate cancer. High-intensity focal ultrasound, focal cryotherapy, photodynamic therapy, irreversible electroporation and focal laser ablation, have been used as treatment modalities for localized prostate cancer treatment. The reported oncologic outcomes vary widely and makes comparisons challenging. All the focal therapies report low rates of complications, and high rates of continence and erectile function preservation. The most common adverse events are hematuria, urinary retention and urinary tract infections. During this period, the initial results of several new technologies including MRI-guided transurethral ultrasound ablation were published. Focal therapy and partial gland ablation for organ-confined prostate cancer is an option for patients with intermediate-risk disease because of its low complication profile and preservation of QOL. Trials comparing the outcome of different focal therapy technologies have not been carried out, and the existing evidence does not point to one approach being clearly superior to others. Long-term oncologic outcome is lacking. Despite this, for men with unilateral intermediate-risk prostate cancer whose disease is often relatively indolent, focal therapy is an appealing option.

Acute and subacute prostate MRI findings after MRI-guided transurethral ultrasound ablation of prostate cancer.

Magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (TULSA) is an emerging method for treatment of localized prostate cancer (PCa). TULSA-related subacute MRI findings have not been previously characterized. To evaluate acute and subacute MRI findings after TULSA treatment in a treat-and-resect setting. Six men with newly diagnosed MRI-visible and biopsy-concordant clinically significant PCa were enrolled and completed the study. Eight lesions classified as PI-RADS 3-5 were focally ablated using TULSA. One- and three-week follow-up MRI scans were performed between TULSA and robot-assisted laparoscopic prostatectomy. TULSA-related hemorrhage was detected as a subtle T1 hyperintensity and more apparent T2 hypointensity in the MRI. Both prostate volume and non-perfused volume (NPV) markedly increased after TULSA at one week and three weeks after treatment, respectively. Lesion apparent diffusion coefficient values increased one week after treatment and decreased nearing the baseline values at the three-week MRI follow-up. The optimal timing of MRI follow-up seems to be at the earliest at three weeks after treatment, when the post-procedural edema has decreased and the NPV has matured. Diffusion-weighted imaging has little or no added diagnostic value in the subacute setting.

Does MRI-guided TULSA provide a targeted approach to ablation?

MRI-guided transurethral ultrasound ablation is an exciting, minimally invasive technology with the potential to provide targeted ablation of prostate cancer tissue. At 3 years, functional outcomes remain good with 76% remaining free from salvage treatment. Future studies using a focal approach may provide evidence for widespread uptake of this technology.

Palliative MRI-guided transurethral ultrasound ablation for symptomatic locally advanced prostate cancer

Purpose Locally advanced prostate cancer can cause bladder outlet obstruction, gross hematuria and frequent hospitalization. While these complications are commonly treated by palliative transurethral resection of the prostate, the improvement is often insufficient. The purpose of this study was to evaluate the safety and feasibility of MRI-guided transurethral ultrasound ablation as an alternative palliative treatment option (pTULSA) for men suffering from symptomatic locally advanced prostate cancer. Methods This prospective, phase one study included 10 men in need of palliative surgical intervention due to urinary retention and gross hematuria caused by locally advanced prostate cancer. Patients were followed for 1 year at 3-month intervals. Time without catheter, time without hematuria, reduction in hospitalization time, and adverse events were measured. Results Ten patients with locally advanced prostate cancer were enrolled, all having continuous catheterization due to urinary retention and nine had gross hematuria before treatment. At 1 week post-pTULSA five patients were catheter-free. At last follow-up catheter-free and gross hematuria-free rates were 70% and 100%, respectively. Average hospitalization time from local complications reduced from 7.3 to 1.4 days in the 6 months before and after pTULSA. No > Grade 2 treatment related adverse events were reported, with all five being urinary tract infections. Conclusions pTULSA appears safe and feasible for palliative ablation of locally advanced prostate cancer. The therapy seems to accomplish long-term hematuria control, can relieve bladder outlet obstruction in selected patients, and seems to reduce the burden of hospitalization due to local complications. Trial Registration Number: NCT03350529

883 - Pivotal trial of MRI-guided transurethral ultrasound ablation in men with localized prostate cancer: Two-year follow-up

883 - Pivotal trial of MRI-guided transurethral ultrasound ablation in men with localized prostate cancer: Two-year follow-up

884 - Five-year outcomes from a prospective phase I study of MRI-guided transurethral ultrasound ablation in men with localized prostate cancer

884 - Five-year outcomes from a prospective phase I study of MRI-guided transurethral ultrasound ablation in men with localized prostate cancer