Focal High Intensity Focused Ultrasound of Unilateral Localized Prostate Cancer: A Prospective Multicentric Hemiablation Study of 111 Patients

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.

Long-term outcomes of salvage transurethral high-dose-rate brachytherapy combined with external beam radiation therapy for anastomotic recurrence of prostate cancer after radical prostatectomy: A retrospective analysis

BACKGROUND

High-dose-rate brachytherapy (HDR-BT) delivers high-dose radiation to local lesions within a short treatment period. There are no reports of salvage transurethral HDR-BT for biochemical recurrence (BCR) after radical prostatectomy. Thus, we aimed to evaluate the usefulness of salvage transurethral HDR-BT with external beam radiation therapy (EBRT) for anastomotic prostate cancer recurrence.

METHODS AND MATERIALS

Patients with postoperative prostate cancer who underwent salvage transurethral HDR-BT with EBRT for anastomotic recurrence at our hospital between January 2002 and July 2009 were retrospectively evaluated. The Kaplan-Meier method was used to estimate biochemical freedom from failure (bFFF), cause-specific survival (CSS), and overall survival (OS) rates.

RESULTS

Nine patients were included in this study. The median follow-up period and age were 13.1 (range 4.3-18.4) years and 67 (range 63-78) years, respectively. The dose of HDR-BT ranged from 13 to 24 Gy per 2 to 5 fractions, while that of EBRT ranged from 30 to 44 Gy per 15 to 22 fractions. The 1-year, 5-year, and 10-year bFFF rates were 77.8%, 41.7%, and 13.9%, respectively. The 10-year and 15-year CSS rates were 100% each. The 10-year and 15-year OS rates were 100% and 64.3%, respectively. Six patients were diagnosed with BCR. Two patients experienced Grade 3 hematuria as a late adverse event. There was no exacerbation of urinary incontinence.

CONCLUSIONS

No prostate cancer-related deaths were observed, even after a long-term follow-up. Salvage transurethral HDR-BT after radical prostatectomy is safe and feasible and may be a useful treatment option.

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.

[Oncological and functional results of focal treatment of localized prostate cancer with HIFU]

INTRODUCTION

In recent years, improved diagnosis of prostate cancer has allowed the development of focal therapy, in order to reduce the morbidity of treatments. Our study assesses the medium-term oncological and functional results of FocalOne® HIFU treatment in localized prostate cancer.

METHODS

This is a retrospective, multicentre study including patients with low- or intermediate-risk localized prostate cancer treated with Focal one HIFU between November 2014 and December 2019. The primary endpoint was the retreatment rate and subgroup analyses were performed to identify predictive factors of retreatment.

RESULTS

One hundred and thirty-seven patients were included with a median follow-up of 25.5 months. Seventy percent of patients had clinical stage T2, 64% had an ISUP score of 2 or 3 on initial biopsies and 38% were treated with hemi-ablation. Follow-up biopsies were performed in 76.6% of patients during follow-up with 21.8% having clinically significant cancers. The retreatment rate at 24 months was 37.2%, with positive biopsies being the primary criterion for retreatment. Patients with a PSA>8ng/mL had a significantly higher retreatment rate. Finally, morbidity remained acceptable with 5.8% of patients requiring reoperation for complications and 21% for de novo erectile dysfunction.

CONCLUSION

Our results are in agreement with those of the literature, seeming to indicate a lower morbidity of the focal treatment by HIFU compared to the radical treatments while offering an acceptable oncological control. Prospective randomized trials are ongoing.

LEVEL OF EVIDENCE: 4

Follow-Up of Men Who Have Undergone Focal Therapy for Prostate Cancer with HIFU-A Real-World Experience

PURPOSE

To determine oncological and functional outcomes and side effects after focal therapy of prostate cancer (PCa) with high-intensity focused ultrasound (HIFU).

METHODS

This retrospective single-center study included 57 consecutive patients with localised PCa. Aged 18-80 with ≤2 suspicious lesions on mpMRI (PIRADS ≥ 3), PSA of ≤15 ng/mL, and an ISUP GG of ≤2. HIFU was performed between November 2014 and September 2018. All men had an MRI/US fusion-guided targeted biopsy (TB) combined with a TRUS-guided 10-core systematic biopsy (SB) prior to focal therapy. HIFU treatment was performed as focal, partial, or hemiablative, depending on the prior histopathology. Follow-up included Questionnaires (IIEF-5, ICIQ, and IPSS), prostate-specific antigen (PSA) measurement, follow-up mpMRI, and follow-up biopsies.

RESULTS

The median age of the cohort was 72 years (IQR 64-76), and the median PSA value before HIFU was 7.3 ng/mL (IQR 5.75-10.39 ng/mL). The median follow-up was 27.5 (IQR 23-41) months. At the time of the follow-up, the median PSA value was 2.5 ng/mL (IQR 0.94-4.96 ng/mL), which shows a significant decrease (p < 0.001). In 17 (29.8%) men, mpMRI revealed a suspicious lesion, and 19 (33.3%) men had a positive biopsy result. Only IIEF values significantly decreased from 16 (IQR 10.75-20.25) to 11.5 (IQR 4.5-17) (p < 0.001). The rate of post-HIFU complications was low, at 19.3% (11 patients). The limitation of this study is the lack of long-term follow-up.

CONCLUSIONS

HIFU as a therapy option for nonmetastatic, significant prostate cancer is effective in the short term for carefully selected patients and shows a low risk of adverse events and side effects.

Urinary outcomes of new ultra-minimally invasive treatments for prostate cancers

PURPOSE OF REVIEW

The aim of this narrative review is to evaluate the current available literature on urinary outcomes following cryotherapy and high-intensity focused ultrasound (HIFU) for localized prostate cancer (PCa).

RECENT FINDINGS

The available literature is heterogeneous in terms of intervention modalities and assessment of urinary outcome measures. Nevertheless, ultra-minimally invasive treatments seem to provide good urinary outcomes. Technological advancement and the adoption of more conservative ablation templates allow for a further reduction of toxicity and better preservation of urinary function. Urinary incontinence occurs in 0-10% of the patients and, is mostly transient. Voiding and storage lower urinary tract symptoms (LUTS) mostly occur in the early postoperative period and rarely require surgical treatment. Focal therapies performed with a salvage intent after external beam radiotherapy have a significantly higher impact on patient's urinary function.

SUMMARY

Ultra-minimally invasive treatment for PCa show a good safety profile concerning urinary function, but consensus on when and how best to assess this is still lacking. Efforts should be made to standardize the report of preoperative and postoperative urinary function to provide higher level of evidence.

Current status and future outlook of ultrasound treatment for prostate cancer

Radical prostatectomy and radiation therapy are the standard treatment options for localized prostate cancer (PC). However, radical prostatectomy may cause the deterioration of urinary and sexual function, and radiation-induced hemorrhagic cystitis and severe rectal bleeding are risk factors for fatal conditions in patients after radiation therapy. With the recent development of magnetic resonance imaging (MRI) for the localization of clinically significant PC (csPC) and treatment modalities, "focal therapy", which cures csPC while preserving anatomical structures related to urinary and sexual functions, has become a minimally invasive treatment for localized PC. Based on the clinical results of transrectal high-intensity focused ultrasound (HIFU) for localized PC in the whole gland and focal therapy, HIFU is considered an attractive treatment option for focal therapy. Recently, the short-term clinical results of transurethral high-intensity directional ultrasound (HIDU) have been reported. With the resolution of some issues, HIDU may be commonly used for PC treatment similar to HIFU. Because HIFU and HIDU have limitations regarding the treatment of patients with large prostate calcifications and large prostate volumes, the proper use of these modalities will enable the treatment of any target area in the prostate. To establish a standard treatment strategy for localized PC, pair-matched and historically controlled studies are required to verify the oncological and functional outcomes of ultrasound treatment for patients with localized PC.

Prediction and Mapping of Intraprostatic Tumor Extent with Artificial Intelligence

Background

Magnetic resonance imaging (MRI) underestimation of prostate cancer extent complicates the definition of focal treatment margins.

Objective

To validate focal treatment margins produced by an artificial intelligence (AI) model.

Design setting and participants

Testing was conducted retrospectively in an independent dataset of 50 consecutive patients who had radical prostatectomy for intermediate-risk cancer. An AI deep learning model incorporated multimodal imaging and biopsy data to produce three-dimensional cancer estimation maps and margins. AI margins were compared with conventional MRI regions of interest (ROIs), 10-mm margins around ROIs, and hemigland margins. The AI model also furnished predictions of negative surgical margin probability, which were assessed for accuracy.

Outcome measurements and statistical analysis

Comparing AI with conventional margins, sensitivity was evaluated using Wilcoxon signed-rank tests and negative margin rates using chi-square tests. Predicted versus observed negative margin probability was assessed using linear regression. Clinically significant prostate cancer (International Society of Urological Pathology grade ≥2) delineated on whole-mount histopathology served as ground truth.

Results and limitations

The mean sensitivity for cancer-bearing voxels was higher for AI margins (97%) than for conventional ROIs (37%, p < 0.001), 10-mm ROI margins (93%, p = 0.24), and hemigland margins (94%, p < 0.001). For index lesions, AI margins were more often negative (90%) than conventional ROIs (0%, p < 0.001), 10-mm ROI margins (82%, p = 0.24), and hemigland margins (66%, p = 0.004). Predicted and observed negative margin probabilities were strongly correlated (R2 = 0.98, median error = 4%). Limitations include a validation dataset derived from a single institution's prostatectomy population.

Conclusions

The AI model was accurate and effective in an independent test set. This approach could improve and standardize treatment margin definition, potentially reducing cancer recurrence rates. Furthermore, an accurate assessment of negative margin probability could facilitate informed decision-making for patients and physicians.

Patient summary

Artificial intelligence was used to predict the extent of tumors in surgically removed prostate specimens. It predicted tumor margins more accurately than conventional methods.

MRI/real-time ultrasound image fusion guided high-intensity focused ultrasound: a prospective comparative and functional analysis of different ablative techniques

BACKGROUND

The aim of this paper was to compare safety and functional outcomes of total, hemi and focal ablation by the latest focal high-intensity focused ultrasound (HIFU) device.

METHODS

This is a prospective study including patients with low to intermediate-risk PCa treated with HIFU by Focal One^® device from 11/2018 to 3/2020. Before the treatment all patients underwent mp-magnetic resonance imaging (MRI) and subsequent MRI/transrectal ultrasound (TRUS) fusion and standard biopsy. Patients were stratified according to the type of ablation: total, hemi- or focal ablation. Functional data (IPSS, Quality of Life [QoL], IIEF-5, maximum flow [Qmax] and post void residual [PVR] at flowmetry) were assessed preoperatively and at 1, 3, 6 and 12 months after treatment. Moreover, the urinary symptoms reported by patients at IPSS questionnaire were divided in "irritative" and "obstructive" and compared.

RESULTS

One hundred patients were enrolled. Median prostate volume and lesion diameter were 46 (IQR 25-75) mL and 10 (IQR 6-13) mm. 15, 50 and 35 patients underwent total, hemi- and focal ablation, respectively. No differences were found between them except for operative time (lower in the focal group, P<0.01). Significant lower incidence of irritative symptoms was identified in the focal group compared to the others (P<0.05 at 1 and 3 months of follow-up). No differences were found among the baseline status and the postoperative assessment in terms of obstructive IPSS items, IIEF-5, QoL, Qmax and PVR (all P value>0.05).

CONCLUSIONS

Our study suggests that patients' specific HIFU tailoring with the MRI/real-time TRUS Guidance by Focal One^® device is able to minimize the side effects of treatment.

Rational Design of Biomaterials to Potentiate Cancer Thermal Therapy

Cancer thermal therapy, also known as hyperthermia therapy, has long been exploited to eradicate mass lesions that are now defined as cancer. With the development of corresponding technologies and equipment, local hyperthermia therapies such as radiofrequency ablation, microwave ablation, and high-intensity focused ultrasound, have has been validated to effectively ablate tumors in modern clinical practice. However, they still face many shortcomings, including nonspecific damages to adjacent normal tissues and incomplete ablation particularly for large tumors, restricting their wide clinical usage. Attributed to their versatile physiochemical properties, biomaterials have been specially designed to potentiate local hyperthermia treatments according to their unique working principles. Meanwhile, biomaterial-based delivery systems are able to bridge hyperthermia therapies with other types of treatment strategies such as chemotherapy, radiotherapy and immunotherapy. Therefore, in this review, we discuss recent progress in the development of functional biomaterials to reinforce local hyperthermia by functioning as thermal sensitizers to endow more efficient tumor-localized thermal ablation and/or as delivery vehicles to synergize with other therapeutic modalities for combined cancer treatments. Thereafter, we provide a critical perspective on the further development of biomaterial-assisted local hyperthermia toward clinical applications.

Real-World Comparative Safety and Effectiveness of Irreversible Electroporation and High-Intensity Focused Ultrasound for Prostate Cancer Ablation

OBJECTIVES

To assess the comparative safety and effectiveness of 2 prostate cancer treatment ablation modalities: irreversible electroporation (IRE) and high-intensity focused ultrasound (HIFU).  METHODS: Two systematic literature reviews (SLRs) and meta-analyses (MAs) on IRE and HIFU were conducted in accordance with PRISMA guidelines. Searches were conducted in PubMed and EMBASE. Independent reviewers assessed literature eligibility and abstracted safety and effectiveness data. Oncological, safety, functional, and quality of life (QOL) outcomes were examined for each technology. MAs were conducted where data quality and availability allowed, using normal methods and a random/mixed effects model, and quality assessments performed.

RESULTS

Fifty-five publications (n = 22 IRE; n = 33 HIFU) were included in the SLRs, and MAs were conducted on negative in-field post-procedure biopsy, prostate-specific antigen (PSA) level reduction, potency, urinary continence, and AE rate outcomes. MAs revealed that IRE patients had lower mean percent PSA level reductions, higher mean rates of in-field negative post-treatment biopsy, and higher rates of potency maintenance than HIFU patients. Most adverse events (AEs) reported were comparable and minor (Grades I, II), with urinary tract infection, dysuria, hematuria, and incontinence or urgency most frequently reported. The proportion of patients experiencing a severe AE (≥Grade III) ranged from 0 to 8% after IRE and HIFU. Both modalities were associated with positive functional outcomes as well as maintenance of QOL after treatment.

CONCLUSIONS

Both IRE and HIFU were found to produce favorable effectiveness outcomes and have low complication rates while minimally impacting patient urinary and erectile function and maintaining overall QOL. These real-world findings can help guide clinical decision making and improve disease management for patients with prostate cancer.

Evolving imaging methods of prostate cancer and the emergence of magnetic resonance imaging guided ablation techniques

Established therapies for prostate cancer (PCa), surgery and radiotherapy, treat the entire gland regardless of the location of the cancerous lesion within the prostate. Although effective, these methods include a significant risk of worsening genitourinary outcomes. Targeted image-guided cancer therapy has gained acceptance through improved PCa detection, localization, and characterization by magnetic resonance imaging (MRI). Minimally-invasive ablative techniques aim to achieve comparable oncological outcomes to radical treatment while preserving genitourinary function. Transurethral ultrasound ablation (TULSA) and next-generation transrectal high-intensity focused ultrasound (HIFU) utilize MRI guidance to thermally ablate prostate tissue under real-time MRI monitoring and active temperature feedback control. Previous trials performed by our group and others, including a large multicenter study in men with localized favorable-risk disease, have demonstrated that TULSA provides effective prostate ablation with a favorable safety profile and low impact on quality of life. Recently, MRI-guided HIFU focal therapy was also shown as a safe and effective treatment of intermediate-risk PCa. Here we review the current literature on ablative techniques in the treatment of localized PCa with a focus on TULSA and HIFU methods.

Focal therapy of localized prostate cancer

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

Salvage high intensity focused ultrasound for residual or recurrent cervical cancer after definitive chemoradiotherapy

Objective

The treatment of residual/recurrent cervical cancer within a previously irradiated area is challenging and generally associated with a poor outcome. Local treatments such as salvage surgery and re-irradiation are usually traumatic and have limited efficacy. High intensity focused ultrasound (HIFU) treatment can directly ablate solid tumors without damaging neighboring healthy tissue. However, the HIFU studies for these patients are limited. Experience gained over the course of 10 years with the use of HIFU for the management of residual/recurrent cervical cancer after chemoradiotherapy is reported herein.

Methods

153 patients with residual/recurrent cervical cancer in a previously irradiated field who received HIFU treatment between 2010 and 2021 were retrospectively analyzed. Adverse effects, survival benefit and factors affecting prognosis were given particular attention.

Results

A total of 36 patients (23.5%) achieved a partial response following HIFU treatment and 107 patients (69.9%) had stable disease. The objective response and disease control rates were 23.5% and 93.5%, respectively. The median progression-free survival (mPFS) and median overall survival (mOS) were 17.0 months and 24.5 months, respectively. Moreover, patients with lesions ≥1.40 cm before HIFU treatment and a shrinkage rate ≥ 30% after treatment had a higher mPFS and mOS, and patients with lesions ≤1.00 cm after HIFU treatment had a higher mPFS (P=<0.05). All the treatment-related adverse events were limited to minor complications, which included skin burns, abdominal pain and vaginal discharge.

Conclusions

HIFU treatment is likely a preferred option for cervical cancer patients with residual disease or recurrence following CRT that can safely improve the local control rate and extend survival.

Focal Therapy for Prostate Cancer: The Impact on Sexual Function

Focal therapy (FT) has emerged as a potential treatment for localized prostate cancer (PCa) with encouraging functional outcomes. According to the compelling evidence based on meta-analyses and recent trials, erectile function (EF) is mostly retained at 6 and 12 months after FT when compared to baseline. These findings are consistent across different energy sources reported to date. However, overall, quality of life, including impotence, was not the endpoint for most studies. Additionally, impotency has not been consistently reported in most of the recent literature. Furthermore, confounding factors such as baseline potency and usage of phosphodiesterase 5 inhibitors (PDE5-I) were also frequently undisclosed. Long-term functional outcomes are awaited. To fully comprehend how FT affects EF, more extensive long-term randomized clinical trials using EF as a primary outcome are needed.

Transrectal Ultrasound in Prostate Cancer: Current Utilization, Integration with mpMRI, HIFU and Other Emerging Applications

Transrectal ultrasound (TRUS) has been an invaluable tool in the assessment of prostate size, anatomy and aiding in prostate cancer (PCa) diagnosis for decades. Emerging techniques warrant an investigation into the efficacy of TRUS, how it compares to new techniques, and options to increase the accuracy of prostate cancer diagnosis. Currently, TRUS is used to guide both transrectal and transperineal biopsy approaches with similar cancer detection rates, but lower rates of infection have been reported with the transperineal approach, while lower rates of urinary retention are often reported with the transrectal approach. Multiparametric MRI has substantial benefits for prostate cancer diagnosis and triage such as lesion location, grading, and can be combined with TRUS to perform fusion biopsies targeting specific lesions. Micro-ultrasound generates higher resolution images that traditional ultrasound and has been shown effective at diagnosing PCa, giving it the potential to become a future standard of care. Finally, high-intensity focused ultrasound focal therapy administered via TRUS has been shown to offer safe and effective short-term oncological control for localized disease with low morbidity, and the precise nature makes it a viable option for salvage and repeat therapy.

Development and future prospective of treatment for localized prostate cancer with high-intensity focused ultrasound

High-intensity focused ultrasound (HIFU) was experimentally used for focal therapy for anti-cancer effects in prostate cancer (PC). Focal therapy is a diagnosis-based investigational treatment option for localized PC that cures clinically significant PC (csPC) while preserving the anatomical structures related to urinary and sexual function based on its spread observed using multi-parametric magnetic resonance imaging (mpMRI). The European Association of Urology indicated that the current status of focal therapy for localized PC was an investigational modality and encouraged prospective recording of outcomes and recruitment of suitable patients in 2018. During the last few years, large-population multi- and single-center prospective studies have investigated focal therapy as a treatment strategy for localized PC. In a multicenter prospective study with 5-year follow-up, failure-free survival, which was defined as avoidance of local salvage therapy (surgery or radiotherapy), systemic therapy, metastases, and prostate cancer-specific death, was 88%. In the previous studies, there was no significant influence on urinary function before and at 3 months after the treatment, although transient impairment was reported 1 month after the treatment. Pad- and leak-free continence was preserved in 80-100% of the patients after treatment. Erectile function was significantly impaired in the initial 3 months after treatment compared to the pretreatment values, but it improved 6 months after the focal therapy in the previous reports. Paired comparison studies and cohort studies with long-term follow-up will contribute to verifying this treatment's clinical outcomes for patients with localized PC.

Clinical application of the therapeutic ultrasound in urologic disease: Part II of the therapeutic ultrasound in urology

This article aimed to review the clinical application and evidence of the therapeutic ultrasound in detail for urological diseases such as prostate cancer, kidney tumor, erectile dysfunction, and urolithiasis. We searched for articles about high-intensity focused ultrasound (HIFU), extracorporeal shock wave therapy, ultrasound lithotripsy, and extracorporeal shockwave lithotripsy (ESWL) in the MEDLINE and Embase. HIFU may be indicated as a primary treatment for low- or intermediate-risk prostate cancer, and salvage therapy for local recurrence as a promising way to address the limitations of current standard therapies. The application of HIFU in treating kidney tumors has scarcely been reported with unsatisfactory results. Evidence indicates that low-intensity shockwave therapy improves subjective and objective erectile function in patients with erectile dysfunction. Regarding the application of ultrasound in stone management, the novel combination of ultrasound lithotripsy and other energy sources in a single probe promises to be a game-changer in efficiently disintegrating large kidney stones in percutaneous nephrolithotomy. ESWL is losing its role in managing upper urinary tract calculi worldwide. The burst-wave lithotripsy and ultrasound propulsion could be the new hope to regain its position in the lithotripsy field. According to our investigations and reviews, cavitation bubbles of the therapeutic ultrasound are actively being used in the field of urology. Although clinical evidence has been accumulated in urological diseases such as prostate cancer, kidney tumor, erectile dysfunction, and lithotripsy, further development is needed to be a game-changer in treating these diseases.

A visualization method for a wide range of rising temperature induced by high-intensity focused ultrasound using a tissue-mimicking phantom

PURPOSE

High-intensity focused ultrasound (HIFU) treatment requires prior evaluation of the HIFU transducer output. A method using micro-capsulated thermochromic liquid crystal (MTLC) to evaluate the temperature distribution in the media during HIFU exposure has been previously developed. However, the color-coded temperature range of commercial MTLC is approximately 10 °C, which is insufficient for temperature measurement for HIFU exposure. We created two layers of tissue-mimicking phantoms with different color-coded temperature ranges, and a new visualization method was developed by utilizing the axisymmetric pressure distribution of a HIFU focus.

METHODS

A two-layer phantom with two sensitivity ranges was created. The HIFU transducer was set to align the focal point to the boundary between the two layers. Images of the upper and lower layers were flipped along the boundary between the two layers such that they overlapped with each other, assuming the pressure distribution of HIFU to be axisymmetric.

RESULTS

The experimental and simulation results were compared to evaluate the accuracy of the phantom temperature measurement. The experimental time profile of the temperature and spatial distribution around the HIFU focus matched well with that of the simulation. However, there is room for improvement in the accuracy in the axial direction of HIFU focus.

CONCLUSION

Users can apply our proposed method in clinical practice to promptly assess the output of the HIFU transducer before treatment.

Focal brachytherapy for localized prostate cancer: 5.7-year clinical outcomes and a pair-matched study with radical prostatectomy

OBJECTIVES

To report experience with focal brachytherapy (FB) and compare its clinical outcomes with those of radical prostatectomy (RP) in localized prostate cancer.

METHODS

Fifty-one patients with low- to intermediate-risk prostate cancer underwent low-dose-rate FB. Survival rates free from biochemical failure (BF), additional treatment (AT) including re-FB, and whole-gland or systemic salvage therapy (ST) were calculated and oncological risk factors were investigated. Patient-reported outcomes on genitourinary function were also assessed. Using propensity scoring, 51 pair-matched RP patients were selected. Oncological control, urinary continence, and ejaculation status after FB and RP were compared.

RESULTS

During a median 5.7-year follow-up, BF, AT, and ST occurred in 12 (24%), 10 (20%), and 4 FB patients (8%), respectively. 6 of 10 AT patients were managed with re-FB alone. In the RP cohort, 3 patients (6%) underwent ST. 5-year BF-free survival rate after FB was 79%. Compared to 5-year ST-free survival rate of 94% after RP, ST-free and AT-free survival rates after FB were 93% (P = 0.813) and 87% (P = 0.049), respectively. Multivariate analyses of FB-treated patients showed that time to PSA nadir was negatively associated with BF and AT (hazard ratio 0.84 and 0.83, respectively, P <0.001 for each). The difference in oncological outcomes between low- and intermediate-risk categories was not significant. At 2 years after FB and RP, pad-free continence rates were 100% and 81%, respectively (P = 0.001). Ejaculation was preserved in 67% and 0% of patients who had been capable of ejaculation at baseline, respectively (P <0.001).

CONCLUSION

In low- to intermediate-risk prostate cancer, FB-treated patients achieved superior genitourinary function compared to pair-matched RP patients. The need for ST was not substantially different between the 2 treatment cohorts. Over half of patients requiring AT could be managed by re-focal treatment rather than whole-gland ST. Early PSA nadir may predict poor oncological control after FB.

Oncological and functional outcome after partial prostate HIFU ablation with Focal-One(®): a prospective single-center study

BACKGROUND

We aimed to evaluate oncological and functional outcomes of index lesion HIFU ablation with Focal-One^®.

MATERIALS AND METHODS

We prospectively assessed treatment-naïve men with localized prostate cancer between 2017 and 2019. Inclusion criteria were stage cT ≤ 2, ≥5 years of life expectancy, grade group ≤3. Multiparametric magnetic resonance was performed before ablation. Patients with a prostate volume of ≥80 ml underwent debulking. Treatment failure was defined as a histologically confirmed tumor that required salvage treatment or androgen deprivation therapy.

RESULTS

One hundred and eighty nine patients were enrolled. Data are presented as median and Interquartile Range (IQR). Median age was 70(11) years. Median baseline PSA was 5.8(3) ng/ml. Fourteen (7.4%) patients had prostate debulking before ablation. 104 (55%) patients underwent targeted ablation, 45 (23.8%) extended targeted ablation, 31 (16.4%) hemiablation, and 9 (4.8%) extended hemiablation. Median targeted ablated volume was 14(9) ml. Ninety-three complications occurred in 63/189 (33.3%) patients within 90 days. There were 77/93 (82.8%) minor (Clavien grade 1-2) and 16/93 (17.2%) major complications (Clavien grade 3a). Thirty-nine patients suffered from genito-urinary infections (Clavien grade 2). Fifteen patients required transurethral resection of the prostate/urethrotomy for recurrent urinary retention (Clavien grade 3a). One patient developed a recto-urethral fistula (Clavien grade 3a) and two long-lasting urinary incontinence. Median PSA nadir was 2.2(2.9) ng/ml. At a median follow-up of 29(15) months, 21/177 (11.9%) patients were treatment failures, 26 on monitoring, and 26 had a further ablation. Multivariable logistic regression found that failure patients had higher PSA (7.8 vs 5.7 ng/ml,p0.001) and double PSA nadir (4.8 vs 2.0 ng/ml, p < 0.001). Higher PSA nadir correlated with a 74% higher probability of failure (OR 1.74 95% CI 1.40-2.16). Cancer in the anterior stroma increased the odds of failure of three folds (OR 3.36 95% CI 1.18-9.53). Two mixed effect models (one for IPSS and one for IEEF-15) were estimated and they showed that time reaches the statistical significance coefficient only for the IEEF-15, meaning that subsequent evaluations of the indicators were significantly lower at each time point.

CONCLUSIONS

Index lesion HIFU ablation demonstrated satisfactory early oncological outcome but anteriorly located tumors had inadequate ablation. Urinary function was well preserved. Sexual function slightly decreased during follow-up.

A systematic review of outcomes after thermal and nonthermal partial prostate ablation

We sought to compare oncologic and functional outcomes between thermal and nonthermal energy partial gland ablation (PGA) modalities. We conducted comprehensive, structured literature searches, and 39 papers, abstracts, and presentations met the inclusion criteria of pre-PGA magnetic resonance imaging, oncologic outcomes of at least 6 months, and systematic biopsies after PGA. Twenty-six studies used thermal ablation: high-intensity focused ultrasound (HIFU), cryotherapy, focal laser ablation, or radiofrequency ablation. In-field recurrence rates ranged from 0 to 36% for HIFU, 6 to 24% for cryotherapy, 4 to 50% for focal laser ablation, and 20 to 25% for radiofrequency ablation. Twelve studies used nonthermal technologies of focal brachytherapy, vascular-targeted photodynamic therapy, or irreversible electroporation. Focal brachytherapy had the lowest reported failure rate of 8%, vascular-targeted photodynamic therapy had >30% positive in-field biopsies, and irreversible electroporation had in-field recurrence rates of 12–35%. PGA was well tolerated, and nearly all patients returned to baseline urinary function 12 months later. Most modalities caused transient decreases in erectile function. Persistent erectile dysfunction was highest in patients who underwent HIFU. Although oncologic outcomes vary between treatment modalities, systematic review of existing data demonstrates that PGA is a safe treatment option for patients with localized prostate cancer.

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Partial gland ablation (PGA) is an emerging prostate cancer treatment that targets the “index lesion,” defined as the largest lesion of the highest grade.

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PGA methods can be broadly characterized by the type of energy used: thermal or nonthermal.

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Patients treated with PGA have fewer treatment-related side effects than patients treated with radical therapies.

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Long-term oncologic outcomes of patients with clinically significant disease are needed to verify the safety of PGA.

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Clarity is needed regarding how to monitor these patients post-PGA, the need for repeat biopsies, and how to use PSA and MRI to monitor for disease progression.

A Review of High-Intensity Focused Ultrasound in Urology

This review provides an introduction to high-intensity focused ultrasound (HIFU) and reviews its historical and current use in urological surgery. Current and historical literature (1927-2020), including that describing trials and review articles in the medical and ultrasonic literature, has been reviewed, using Pub Med and Cochrane search engines. HIFU is currently one of a number of treatments for prostate cancer, both as a primary treatment that can be repeated, and as a salvage treatment post-radiotherapy. HIFU is not yet sufficiently mature to be a standard treatment for renal cancer or other urological diseases, although there has been some success in early clinical trials. As the technology improves, this situation is likely to change. HIFU has been understood as a concept for a century, and has been applied in experimental use for half that time. It is now an accepted treatment with low morbidity in many diseases outside the scope of this review. In urological surgery, prostate HIFU is accepted as a localised treatment in selected cases, with potentially fewer side effects than other localised therapies. Currently the treatment for renal cancer is hindered by the perinephric fat and the position of the kidneys behind the ribs; however, as the technology improves with image fusion, faster treatments, and the ability with phased array transducers and motion compensation to overcome the problems caused by the ribs and breathing, successful treatment of kidney tumours will become more of a reality. In due course, there will be a new generation of machines for treating prostate cancer. These devices will further minimise the side effects of radical treatment of prostate cancer.

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

CONTEXT

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

OBJECTIVE

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

EVIDENCE ACQUISITION

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

EVIDENCE SYNTHESIS

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

CONCLUSIONS

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

PATIENT SUMMARY

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

Focal therapy for prostate cancer: Making the punishment fit the crime

BACKGROUND

Focal therapy is recently gaining popularity as an intermediate option between active surveillance and whole-gland treatment for localized prostate cancer.

OBJECTIVE

This comprehensive review aims to present the different focal therapy technologies available to date while tackling the rationale for focal treatment, its indications, principles and outcomes of each technique.

EVIDENCE ACQUISITION

A comprehensive review of the PubMed, Embase, and Web of Science was done. Keywords used for research were: "prostate cancer"; "focal therapy"; "focal treatment"; "High-Intensity Focal Ultrasound"; "cryotherapy"; "photodynamic therapy"; "focal laser ablation"; "irreversible electroporation"; "focal brachytherapy" and "gold nanoparticle directed therapy". Accepted languages were English and French.

EVIDENCE SYNTHESIS

Choosing the best candidate for focal therapy is crucial (localized small to medium sized Gleason≤7 lesions). Focal high-intensity focal ultrasound has shown excellent survival rates at 5 years, while maintaining good functional outcomes (urinary continence and erectile function). Focal cryotherapy, one of the oldest focal treatments for prostate cancer, has shown good oncologic outcomes, with good continence rates and fair erectile function rates. Focal laser ablation seems a safe and feasible technique, with promising results. Irreversible electroporation has demonstrated good survival outcomes with no biochemical recurrence or disease relapse in the preliminary studies. Focal brachytherapy has a good toxicity profile, a good biochemical outcome, and gives a sustained quality of life. Finally, gold nanoparticle directed therapy is safe and is being studied in current trials.

CONCLUSION

While proven to be safe in terms of continence and sexual aspects, the challenge remains to better assess oncological outcomes of these techniques in randomized longer follow-up studies.

Focal High-Intensity Focused Ultrasound Ablation of the Prostate

With the advancement of early detection tools for prostate cancer and ability to better localize disease, there has been increased interest in focal or targeted therapies that carry less morbidity than traditional whole-gland treatments. The Sonablate^® high-intensity focused ultrasound (HIFU) device has Food and Drug Administration (FDA) 510(K) clearance in the United States for ablation of prostate tissue. HIFU utilizes an ultrasound (US) transducer that focuses US beams on a preset point as much as 4 cm from the energy source without injuring intervening tissue. The Sonablate system guides the surgeon step-by-step to perform effective ablation of a target lesion. The surgeon can assess treatment effect with tissue change monitoring, and care is taken to prevent rectal wall injury. We believe hemiablation is the most favorable focal HIFU treatment to optimize cancer control and minimize the side effects associated with whole gland therapy. We recommend considering HIFU ablation as an extension of active surveillance rather than definitive treatment. Further research on long-term oncologic and functional outcomes is warranted.

Basics in Magnetic Resonance guided Focused Ultrasound: technical basis and clinical application. A brief overview

First applications of high focused ultrasound as intracranial ablative therapy were firstly described in early 50’. Since then, the technological innovations have shown an increasingly safe and effective face of this technique. And in the last few years, Magnetic Resonance (MR) guided Focused Ultrasound (gFUS) has become a valid minimally invasive technique in the treatment of several diseases, from bone tumors to symptomatic uterine fibroids or essential tremors. MR guidance, through the tomographic view, offers the advantage of an accurate target detection and treatment planning. Moreover, real-time monitoring sequences allow to avoid non-target ablation. An adequate knowledge of FUS is essential to understand its clinical effectiveness. Therefore, this brief review aims to debate the physical characteristics of US and the main fields of clinical application.

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

CONTEXT

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

OBJECTIVE

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

EVIDENCE ACQUISITION

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

EVIDENCE SYNTHESIS

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

CONCLUSIONS

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

PATIENT SUMMARY

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

Focal therapy for primary and salvage prostate cancer treatment: a narrative review

Despite innovations in surgical technology and advancements in radiation therapy, radical treatments for clinically localized prostate cancer are associated with significant patient morbidity, including both urinary and sexual dysfunction. This has created a vital need for therapies and management strategies that provide an acceptable degree of oncologic efficacy while mitigating these undesirable side effects. Successful developments in screening approaches and advances in prostate imaging have allowed clinicians to identify, localize, and more precisely target early cancers. This has afforded urologists with an important opportunity to develop and employ focal ablation techniques that selectively destroy tumors while preserving the remainder of the gland, thus avoiding detrimental treatment effects to surrounding sensitive structures. A lack of high-level evidence supporting such an approach had previously hindered widespread adoption of focal treatments, but there are now numerous published clinical trials which have sought to establish benchmarks for safety and efficacy. As the clinical evidence supporting a potential role in prostate cancer treatment begins to accumulate, there has been a growing acceptance of focal therapy in the urologic oncology community. In this narrative review article, we describe the techniques, advantages, and side effect profiles of the most commonly utilized focal ablative techniques and analyze published clinical trial data supporting their evolving role in the prostate cancer treatment paradigm.

Analysis of oncological outcomes of whole-gland therapy with high-intensity focused ultrasound for localized prostate cancer in clinical and technical aspects: a retrospective consecutive case-series analysis with a median 5-year follow-up

PURPOSE

This study aimed to analyze technical and clinical factors related to oncological outcomes in patients with localized prostate cancer (PC) who were treated with whole-gland high-intensity focused ultrasound (HIFU).

MATERIALS AND METHODS

From 2007-2014, patients diagnosed with localized PC who underwent whole-gland HIFU were consecutively included retrospectively. Biochemical failure was defined according to the Phoenix ASTRO guidelines. The relationship between oncological outcomes and technical and clinical factors was evaluated.

RESULTS

The study cohort included 428 patients. The median age was 67 years, and the median prostate-specific antigen level was 7.61 ng/mL. Patient risk classifications were low (n = 102), intermediate (n = 240), and high (n = 86). Biochemical disease-free survival rates of patients with HIFU for localized PC in the total, low-, intermediate-, and high-risk groups according to D'Amico risk groups over a median follow-up period of 5 years (range 9-144) were 68.4%, 80.4%, 65.6%, and 61.6%, respectively. In multivariate logistic regression analyses to predict biochemical failure of the treatment, neoadjuvant hormonal therapy (NHT) in the high-risk group (OR 0.225, p = 0.015), and compression method in the low- (OR 0.178, p = 0.030), intermediate- (OR0.291, p < 0.0001), and high-risk (OR 0.316, p = 0.049) groups were significant factors that reduced the risk of biochemical failure after treatment. There were no significant differences in complications between patients treated with compression and those treated conventionally.

CONCLUSIONS

NHT may potentially improve oncological outcomes for patients in the high-risk group, and compression methods can improve the oncological outcomes of whole-gland therapy with HIFU.

Heating technology for malignant tumors: a review

The therapeutic application of heat is very effective in cancer treatment. Both hyperthermia, i.e., heating to 39-45 °C to induce sensitization to radiotherapy and chemotherapy, and thermal ablation, where temperatures beyond 50 °C destroy tumor cells directly are frequently applied in the clinic. Achievement of an effective treatment requires high quality heating equipment, precise thermal dosimetry, and adequate quality assurance. Several types of devices, antennas and heating or power delivery systems have been proposed and developed in recent decades. These vary considerably in technique, heating depth, ability to focus, and in the size of the heating focus. Clinically used heating techniques involve electromagnetic and ultrasonic heating, hyperthermic perfusion and conductive heating. Depending on clinical objectives and available technology, thermal therapies can be subdivided into three broad categories: local, locoregional, or whole body heating. Clinically used local heating techniques include interstitial hyperthermia and ablation, high intensity focused ultrasound (HIFU), scanned focused ultrasound (SFUS), electroporation, nanoparticle heating, intraluminal heating and superficial heating. Locoregional heating techniques include phased array systems, capacitive systems and isolated perfusion. Whole body techniques focus on prevention of heat loss supplemented with energy deposition in the body, e.g., by infrared radiation. This review presents an overview of clinical hyperthermia and ablation devices used for local, locoregional, and whole body therapy. Proven and experimental clinical applications of thermal ablation and hyperthermia are listed. Methods for temperature measurement and the role of treatment planning to control treatments are discussed briefly, as well as future perspectives for heating technology for the treatment of tumors.

[High-intensity focused ultrasound for locally prostate cancer: An Afro-Caribbean single-center study]

INTRODUCTION

High-intensity focused ultrasound (HIFU) has proved to be effective in the treatment of localized prostate cancer. The aim of this prospective study is to assess their first oncological and functional results in an Afro-Caribbean population.

METHODS

From May 2018 to January 2020, 77 patients issued from French West Indies were included. Several treatments were carried out: whole-gland treatment hemi or focal ablation; in a primary setting (group I) or a salvage therapy (group II). PSA level was assessed at 2, 6, 9 and 12 months. MpMRI and post HIFU biopsy were performed between 6 and 9 months postoperatively. Continence, urinary end erectile functions were assessed by ICS, IPSS and IIEF scores.

RESULTS

Groupe I included 71.2% patients, group II, 28.8%. The median age was 75.4 years [IQR 69.6-79.4]. The median follow-up was 8.3 months [IQR 3.5-12.25]. At inclusion, PSA was 7.7ng/ml [IQR 5.5-11.2] in group I, and 5.9ng/ml [IQR 4.4-7.9] in group II. In the whole population, there was 73.5% negative biopsies; 14.7% of the biopsies were positive in treated zone and 11.8% in non-treated zone. Regarding morbidities, urinary incontinence appeared in 7.5% and erectile dysfunction rate was 13.2%.

CONCLUSION

Our study reveals the first experience of HIFU by Focal One® device in an Afro-Caribbean population. It seems to be a safe and reproducible treatment with acceptable oncological results and low genitourinary morbidity. Long term follow-up and a higher number of patients are necessary to validate these results.

Ultrasound Therapy, Chemotherapy and Their Combination for Prostate Cancer

Prostate cancer is the second leading cause of cancer death in men. Its current treatment includes various physical and chemical approaches for the localized and advanced prostate cancer [e.g. metastatic castrate resistant prostate cancer (mCRPC)]. Although many new drugs are now available for prostate cancer, none is suitable for local treatment that can reduce adverse effects often associated with the current physical treatment. Of the drugs approved by FDA for mCRPC, the best mean improvement in overall survival is only about 4.8 months. Therefore, there is a need for improved treatment approaches for prostate cancer, especially drug-resistant cancer.

Ultrasound therapy represents a useful new physical approach for the drug-resistant cancer treatment by facilitating the entry of the related chemotherapy drug into the target cancer cells. There are two versions of ultrasound: High Intensity Focused Ultrasound (HIFU) and Low Intensity Pulsed Ultrasound (LIPUS). HIFU has been a promising treatment option for prostate cancer due to its noninvasiveness and various biological effects on cancer tissue. It has been approved for the treatment of cancer and in recent years there have been numerous findings suggesting HIFU can reduce cancer cell viability and possibly reverse the spread of cancerous tumors. LIPUS is currently being studied as an alternative treatment option for prostate cancer. Preliminary studies have found LIPUS to reduce cancer cell viability without the side effects seen in HIFU. Reversible cell membrane damage caused by LIPUS could allow increased uptake of anticancer drugs, enhancing cytotoxicity and death of cancer cells. In this way, a low dose of anticancer drug is more effective toward cancer cells while there is less damage to normal cells. The combination of LIPUS with certain chemotherapeutic agents can be an exciting physical-chemical combination therapy for prostate cancer. This review will focus on this topic as well as the clinical use of HIFU to provide an understanding of their current use and future potential role for prostate cancer therapy.

Salvage interstitial laser thermal therapy under MRI guidance (MRgFLA) for high-intensity focal ultrasound (HIFU) recurrences: feasibility study

While focal therapy (FT) is increasingly endorsed for treating localized prostate cancer in the appropriately selected patient, management of recurrences following FT is not well-established in the literature. This case series describes three patients who received high-intensity focal ultrasound (HIFU) for primary treatment followed by focal laser interstitial thermal therapy (FLTT) for salvage therapy treated in the context of an ongoing clinical trial. Evaluation of these reported patients demonstrates that FLTT is feasible in the salvage setting with promising short-term oncologic outcomes and with the potential to preserve functional outcomes. Repeat focal therapy for previous failures is feasible however, it requires sophisticated imaging modalities for the accurate identification of recurrence and treatment of the tumor.

Available evidence on HIFU for focal treatment of prostate cancer: a systematic review

PURPOSE

Prostate cancer (PCa) is the second most common oncologic disease among men. Radical treatment with curative intent provides good oncological results for PCa survivors, although definitive therapy is associated with significant number of serious side-effects. In modern-era of medicine tissue-sparing techniques, such as focal HIFU, have been proposed for PCa patients in order to provide cancer control equivalent to the standard-of-care procedures while reducing morbidities and complications. The aim of this systematic review was to summarise the available evidence about focal HIFU therapy as a primary treatment for localized PCa.

MATERIAL AND METHODS

We conducted a comprehensive literature review of focal HIFU therapy in the MEDLINE database (PROSPERO: CRD42021235581). Articles published in the English language between 2010 and 2020 with more than 50 patients were included.

RESULTS

Clinically significant in-field recurrence and out-of-field progression were detected to 22% and 29% PCa patients, respectively. Higher ISUP grade group, more positive cores at biopsy and bilateral disease were identified as the main risk factors for disease recurrence. The most common strategy for recurrence management was definitive therapy. Six months after focal HIFU therapy 98% of patients were totally continent and 80% of patients retained sufficient erections for sexual intercourse. The majority of complications presented in the early postoperative period and were classified as low-grade.

CONCLUSIONS

This review highlights that focal HIFU therapy appears to be a safe procedure, while short-term cancer control rate is encouraging. Though, second-line treatment or active surveillance seems to be necessary in a significant number of patients.

A Breast-Specific MR Guided Focused Ultrasound Platform and Treatment Protocol: First-in-Human Technical Evaluation

OBJECTIVE

This paper presents and evaluates a breast-specific magnetic resonance guided focused ultrasound (MRgFUS) system. A first-in-human evaluation demonstrates the novel hardware, a sophisticated tumor targeting algorithm and a volumetric magnetic resonance imaging (MRI) protocol.

METHODS

At the time of submission, N = 10 patients with non-palpable T0 stage breast cancer have been treated with the breast MRgFUS system. The described tumor targeting algorithm is evaluated both with a phantom test and in vivo during the breast MRgFUS treatments. Treatments were planned and monitored using volumetric MR-acoustic radiation force imaging (MR-ARFI) and temperature imaging (MRTI).

RESULTS

Successful technical treatments were achieved in 80 % of the patients. All patients underwent the treatment with no sedation and 60 % of participants had analgesic support. The total MR treatment time ranged from 73 to 114 minutes. Mean error between desired and achieved targeting in a phantom was 2.9 ±1.8 mm while 6.2 ±1.9 mm was achieved in patient studies, assessed either with MRTI or MR-ARFI measurements. MRTI and MR-ARFI were successful in 60 % and 70 % of patients, respectively.

CONCLUSION

The targeting accuracy allows the accurate placement of the focal spot using electronic steering capabilities of the transducer. The use of both volumetric MRTI and MR-ARFI provides complementary treatment planning and monitoring information during the treatment, allowing the treatment of all breast anatomies, including homogeneously fatty breasts.

MRI-guided Focused Ultrasound Ablation for Localized Intermediate-Risk Prostate Cancer: Early Results of a Phase II Trial

Background To reduce adverse effects of whole-gland therapy, participants with localized clinically significant prostate cancer can undergo MRI-guided focal therapy. Purpose To explore safety and early oncologic and functional outcomes of targeted focal high-intensity focused ultrasound performed under MRI-guided focused ultrasound for intermediate-risk clinically significant prostate cancer. Materials and Methods In this prospective phase II trial, between February 2016 and July 2019, men with unifocal clinically significant prostate cancer visible at MRI were treated with transrectal MRI-guided focused ultrasound. The primary end point was the 5-month biopsy (last recorded in December 2019) with continuation to the 24-month follow-up projected to December 2021. Real-time ablation monitoring was performed with MR thermography. Nonperfused volume was measured at treatment completion. Periprocedural complications were recorded. Follow-up included International Prostate Symptom Score (IPSS) and International Index of Erectile Function-15 (IIEF-15) score at 6 weeks and 5 months, and multiparametric MRI and targeted biopsy of the treated area at 5 months. The generalized estimating equation model was used for statistical analysis, and the Holm method was used to adjust P value. Results Treatment was successfully completed in all 44 men, 36 with grade group (GG) 2 and eight with GG 3 disease (median age, 67 years; interquartile range [IQR], 62-70 years). No major treatment-related adverse events occurred. Forty-one of 44 participants (93%; 95% CI: 82, 98) were free of clinically significant prostate cancer (≥6 mm GG 1 disease or any volume ≥GG 2 disease) at the treatment site at 5-month biopsy (median, seven cores). Median IIEF-15 and IPSS scores were similar at baseline and at 5 months (IIEF-15 score at baseline, 61 [IQR, 34-67] and at 5 months, 53 [IQR, 24-65.5], P = .18; IPSS score at baseline, 3.5 [IQR, 1.8-7] and at 5 months, 6 [IQR, 2-7.3], P = .43). Larger ablations (≥15 cm³) compared with smaller ones were associated with a decline in IIEF-15 scores at 6 weeks (adjusted P < .01) and at 5 months (adjusted P = .07). Conclusion Targeted focal therapy of intermediate-risk prostate cancer performed with MRI-guided focused ultrasound ablation was safe and had encouraging early oncologic and functional outcomes. © RSNA, 2021 Online supplemental material is available for this article See also the editorial by Tempany-Afdhal in this issue.

Spine metastasis in patients with prostate cancer: Survival prognosis assessment

BACKGROUND

Patients presenting spine metastasis (SpM) from prostate cancer (PC) form a heterogeneous population, through this study, we aimed to clarify and update their prognostic assessment.

METHODS

The patient data used in this study was obtained from a French national multicenter database of patients treated for PC with SpM between 2014 and 2017. A total of 72 patients and 365 SpM cases were diagnosed.

RESULTS

The median overall survival time for all patients following the event of SpM was 28.8 months. First, we identified three significant survival prognostic factors of PC patients with SpM: good Eastern Cooperative Oncology Group/World Health Organization personnel status (Status 0 hazard ratio [HR]: 0.031, 95% confidence interval [CI]: 0.008-0.127; p < .0001) or (Status 1 HR: 0.163, 95% CI: 0.068-0.393; p < .0001) and SpM radiotherapy (HR: 2.923, 95% CI: 1.059-8.069; p < .0001). Secondly, the presence of osteolytic lesions of the spine (vs. osteoblastic) was found to represent an independent prognosis factor for longer survival [HR: 0.424, 95% CI: 0.216-0.830; p = .01]. Other factors including the number of SpM, surgery, extraspinal metastasis, synchrone metastasis, metastasis-free survival, and SpM recurrence were not identified as being prognostically relevant to the survival of patients with PC.

CONCLUSION

Survival and our ability to estimate it in patients presenting PC with SpM have improved significantly. Therefore, we advocate the relevance of updating SpM prognostic scoring algorithms by incorporating data regarding the timeline of PC as well as the presence of osteolytic SpM to conceive treatments that are adapted to each patient.

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

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

Visibility of significant prostate cancer on multiparametric magnetic resonance imaging (MRI)-do we still need contrast media?

Objectives

To assess the visibility of clinically significant prostate cancer (PCA) lesions on the sequences multiparametric MRI of the prostate (mpMRI) and to evaluate whether the addition of dynamic contrast–enhanced imaging (DCE) improves the overall visibility.

Methods

We retrospectively evaluated multiparametric MRI images of 119 lesions in 111 patients with biopsy-proven clinically significant PCA. Three readers assigned visual grading scores for visibility on each sequence, and a visual grading characteristic analysis was performed. Linear regression was used to explore which factors contributed to visibility in individual sequences.

Results

The visibility of lesions was significantly better with mpMRI when compared to biparametric MRI in visual grading characteristic (VGC) analysis, with an AUC_VGC of 0.62 (95% CI 0.55–0.69; p < 0.001). This benefit was seen across all readers. Multivariable linear regression revealed that a location in the peripheral zone was associated with better visibility on T2-weighted imaging (T2w). A higher Prostate Imaging-Reporting and Data System (PI-RADS) score was associated with better visibility on both diffusion-weighted imaging (DWI) and DCE. Increased lesion size was associated with better visibility on all sequences.

Conclusions

Visibility of clinically significant PCA is improved by using mpMRI. DCE and DWI images independently improve lesion visibility compared to T2w images alone. Further research into the potential of DCE to impact on clinical decision-making is suggested.

Key Points

• DCE and DWI images independently improve clinically significant prostate cancer lesion visibility compared to T2w images alone.

• Multiparametric MRI (DCE, DWI, T2w) achieved significantly higher visibility scores than biparametric MRI (DWI, T2w).

• Location in the transition zone is associated with poor visibility on T2w, while it did not affect visibility on DWI or DCE.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-020-07494-1.

Magnetic resonance imaging of the prostate after focal therapy with high-intensity focused ultrasound

For clinically significant, locally confined prostate cancer, whole-gland radical prostatectomy and radiotherapy are established effective treatment strategies that, however, come at a cost of significant morbidity related to urinary and sexual side effects. The concept of risk stratification paired with a better understanding of prognostic factors has led to the development of alternative management options including active surveillance and focal therapy for appropriately selected patients with localized disease. High-intensity focused ultrasound (HIFU) is one such minimally invasive, image-guided treatment option for prostate cancer. Due to the relative novelty of HIFU and the increased use of magnetic resonance imaging in prostate cancer, many radiologists are not yet familiar with imaging findings related to HIFU, their temporal evolution as well as imaging appearance of recurrent disease after this type of focal therapy. HIFU induces sharply demarcated, localized coagulative necrosis of a tumor through thermal energy delivered via an endorectal or transurethral ultrasound transducer. In this pictorial review, we aim at providing relevant background information that will guide the reader through the general principles of HIFU in the prostate, as well as demonstrate the imaging appearance of expected post-HIFU changes versus recurrent tumor.

Ablative options for prostate cancer management

This review provides an overview of the available ablative options for prostate cancer (PCa) management. It contemplates the ablative concepts and the role of prostate ablation in different settings, from primary treatment to repeat ablation, and as an alternative to radiorecurrent disease. Improvements in prostate imaging have allowed us to ablate prostate lesions through thermal, mechanical, and vascular-targeted sources of energy. Partial gland ablation (PGA) has an emerging role in the management of localized PCa because toxicity outcomes have been proven less harmful compared with whole-gland treatments. Although long-term oncological outcomes are yet to be consolidated in comparative studies, recent large series and prospective studies in PGA have reported encouraging results. A second ablation after disease recurrence has demonstrated low toxicity, and future studies must define its potential to avoid radical treatments. PGA is an attractive option for PCa management in different scenarios because of its low-toxicity profile. As expected, recurrence rates are higher than those seen in whole-gland procedures. Long-term oncological outcomes of primary and salvage options are required to endorse it among the standard treatments.

The primary treatment of prostate cancer with high-intensity focused ultrasound: A systematic review and meta-analysis

BACKGROUND

We systematically evaluated the evidences on oncological and functional outcomes of high-intensity focused ultrasound (HIFU) as the primary treatment for localized prostate cancer (PCa).

METHODS

A systematic review was used Medline, Embase, and the Cochrane Library from the inception of each database. The review analyzed the oncological and functional outcomes of HIFU in the treatment of PCa. The RevMan 5.3 software was used for quantity analysis incidence of complications.

RESULTS

Twenty-seven articles were included for analysis with a total of 7393 patients. Eighteen studies investigated the whole-gland HIFU, and the duration of follow-up ranged from 2 to 168 months. After whole-gland HIFU, the mean prostate-specific antigen (PSA) nadir was found to be 0.4 to 1.95 ng/mL and the mean time to PSA nadir was 2.4 to 5.4 months. The rate of positive biopsy after HIFU was 4.5% to 91.1%. Meta-analysis revealed the incidences of urinary incontinence, impotence, urinary obstruction, retention, and infection was 10%, 44%, 15%, 11%, 7%, respectively. Nine studies investigated partial-gland HIFU, and the duration of follow-up was 1 to 131 months. After partial-gland HIFU, the mean PSA nadir was 1.9 to 2.7 ng/mL and the mean time to PSA nadir 5.7 to 7.3 months. The rate of positive biopsy after HIFU in the treatment area was 14% to 37.5%. Meta-analysis revealed the incidences of urinary incontinence, impotence, urinary obstruction, retention, and infection was 2%, 21%, 2%, 9%, 11%, respectively.

CONCLUSIONS

Early evidence suggested the partial-gland HIFU was safer than whole-gland HIFU, and they had similar oncological outcomes. More prospective randomized controlled trials of whole-gland and partial-gland HIFU for PCa was needed.

Outcome selection, measurement and reporting for new surgical procedures and devices: a systematic review of IDEAL/IDEAL-D studies to inform development of a core outcome set

BACKGROUND

Outcome selection, measurement and reporting for the evaluation of new surgical procedures and devices is inconsistent and lacks standardization. A core outcome set may promote the safe and transparent evaluation of surgical innovations. This systematic review examined outcome selection, measurement and reporting in studies conducted within the IDEAL (Idea, Development, Exploration, Assessment and Long-term monitoring) framework to examine current practice and inform the development of a core outcome set for early-phase studies of surgical procedures/devices.

METHODS

Web of Science and Scopus citation searches were performed to identify author-reported IDEAL/IDEAL-D studies for any surgical procedure/device. Outcomes were extracted verbatim, including contextual information regarding outcome selection and measurement. Outcomes were categorized to inform a conceptual framework of outcome domains relevant to evaluating innovation.

RESULTS

Some 48 studies were identified. Outcome selection, measurement and reporting varied widely across studies in different IDEAL stages. From 1737 outcomes extracted, 22 domains specific to evaluating innovation were conceptualized under seven broad categories: procedure completion success/failure; modifications; unanticipated events; surgeons' experiences; patients' experiences; resource use specific to the innovative procedure/device; and other innovation-specific outcomes. Most innovation-specific outcomes were measured and reported in only a small number of studies.

CONCLUSION

This review highlighted the need for guidance and standardization in outcome selection and reporting in the evaluation of new surgical procedures/devices. Novel outcome domains specific to innovation have been identified to establish a core outcome set for future evaluations of surgical innovations.

Erectile function after focal therapy for localized prostate cancer: a systematic review

Focal therapy modalities achieved interest in the management of prostate cancer (PCa) over the last a few years. This systematic review was aimed to investigate erectile function after focal therapy for localized PCa. Twenty-six out of 1287 reports were identified through a database systematic search in MEDLINE, EMBASE, and Web of Science, supplemented with hand search, on June 1st, 2020, according to PRISMA guidelines. Focal therapy modalities investigated were cryotherapy, high-intensity focused ultrasound (HIFU), photodynamic therapy (TOOKAD), irreversible electroporation (IRE), and focal radiotherapy (RT) (i.e. brachytherapy or stereotactic RT). Overall, reported sexual function outcomes after these treatment modalities were generally good, with many studies reporting a complete recovery of EF at 1-year follow-up. However, the quality of current evidence is affected both by the lack of well-conducted comparative studies and by a significant heterogeneity in terms of study design, study population, erectile and sexual function assessment modalities.

Focused ultrasound and prostate cancer

Focused ultrasound (FUS) has been utilized for the treatment of localized prostate cancer. Initially, FUS was performed as a whole-gland treatment comparable to radical prostatectomy or radiation therapy. However, after overall downward stage migration due to health screening programs involving prostate-specific antigen testing, as well as advances in conservative or observative strategies such as active surveillance, FUS has evolved from a whole-gland treatment to a focal treatment. This new treatment technique aims to ablate tumors while preserving the normal prostate tissue, thereby ensuring better preservation of urinary and erectile function. In this article, we review the mechanism and clinical outcomes of the FUS procedure.