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

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.

Acoustodynamic Covalent Materials Engineering for the Remote Control of Physical Properties Inside Materials

Advances in vat photopolymerization (VP) 3D printing (3DP) technology enable the production of highly precise 3D objects. However, it is a major challenge to create dynamic functionalities and to manipulate the physical properties of the inherently insoluble and infusible cross-linked material generated from VP-3DP without reproduction. The fabrication of light- and high-intensity focused ultrasound (HIFU)-responsive cross-linked polymeric materials linked with hexaarylbiimidazole (HABI) in polymer chains based on VP-3DP is reported here. Although the photochemistry of HABI produces triphenylimidazolyl radicals (TPIRs) during the process of VP-3DP, the orthogonality of the photochemistry of HABI and photopolymerization enables the introduction of reversible cross-links derived from HABIs in the resulting 3D-printed objects. While photostimulation cleaves a covalent bond between two imidazoles in HABI to generate TPIRs only near the surface of the 3D-printed objects, HIFU triggers cleavage in the interior of materials. In addition, HIFU travels beyond an obstacle to induce a response of HABI-embedded cross-linked polymers, which cannot be attainable with photostimulation. The present system would be beneficial for tuning the physical properties and recycling of various polymeric materials, but it will also open the door for pinpoint modification, healing, and reshaping of materials when coupled to various dynamic covalent materials.

Functional outcomes and safety of focal therapy for prostate cancer: a systematic review on results and patient-reported outcome measures (PROMs)

INTRODUCTION

Focal therapy (FT) is a promising alternative with curative intent for Low- to Intermediate-risk localized Prostate Cancer (PCa), claiming better functional outcomes and safety profile than standard whole-gland treatments. Ten different FT modalities have been described in the literature. The objective of our narrative review is to evaluate the safety profile and functional outcomes of these different modalities and the current most used tools of assessment for those outcomes.

MATERIAL AND METHODS

Literature search was performed on 21st February 2023 using PubMed, EMBASE, and Scopus, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA). Articles reporting whole-gland treatments were excluded. All articles reporting functional outcomes were included.

RESULTS

One-hundred-seven studies, reporting data on 6933 patients, were included (26 on High Intensity Focal Ultrasound, 22 on Focal Cryotherapy, 14 on Irreversible Electroporation, 11 on Focal brachytherapy, 10 on Focal Laser Ablation, 8 on Photodynamic Therapy, 3 on Microwave ablation, 3 on Robotic Partial Prostatectomy, 2 on bipolar Radio Frequency Ablation, 1 on Prostatic Artery Embolization, and 7 studies comparing different FTs). Post-operative pad-free rate ranged between 92.3-100%. Greater heterogeneity exists considering the Change in Erectile Function, with Changing in Erectile function- rates ranging between 0-94.4% (Cryotherapy). The most used Patient-Reported Outcome Measures (PROMs) were the International Prostate Symptom Score and the International Index of Erectile Function for incontinence/urinary function and potency, respectively. The most common reported complications were hematuria, infections, and urethral strictures, with rates widely ranging among different treatments. The Clavien-Dindo Classification was the most used (40/88 papers) to describe adverse events.

CONCLUSION

FT is a promising treatment for localized PCa, achieving excellent results in terms of safety and functional outcomes. There is a wide heterogeneity in the definition of PROMS and time of collection between studies. High quality comparative studies with standard treatments are needed to reinforce these findings.

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.

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.

Medium-term Oncological Efficacy and Patient-reported Outcomes After Focal High-intensity Focused Ultrasound: The FOXPRO Trial

BACKGROUND

Multiparametric magnetic resonance imaging (mpMRI)/transrectal ultrasound (TRUS) fusion-guided high-intensity focused ultrasound (HIFU) is a focal treatment option for MRI-visible localized prostate cancer (PCa). High-quality evidence regarding the clinical efficacy remains limited.

OBJECTIVE

To assess medium-term oncological efficacy along with patient-reported outcome measures (PROMs).

DESIGN, SETTING, AND PARTICIPANTS

This prospective single-center cohort study was performed from 2014 to 2020. Patients with primary International Society of Urological Pathologists (ISUP) grade group (GG) ≤2 by combined MRI/TRUS fusion and systematic prostate biopsy and prostate-specific antigen (PSA) <10 ng/ml were included.

INTERVENTION

MRI/TRUS fusion-guided focal HIFU therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was the cancer-free rate of the HIFU-treated lesion by biopsy after 1 yr. Secondary endpoints included salvage treatment-free survival (STFS), metastasis-free survival (MFS), overall survival (OS), and PROMs according to International Consortium for Health Outcomes Measurement recommendations.

RESULTS AND LIMITATIONS

Fifty patients were included (median [range] age 68 [48-80] yr; median PSA 6.5 [1.2-9.9] ng/ml; GG 1 54% [n = 27], and GG 2 46% [n = 23]). The median (range) PSA decrease from baseline to 12 mo was 51% (35.9-72.7%). In total, 37/50 patients (74%) underwent a 1-yr biopsy. PCa was detected in 23 patients (46%; GG 1 20% [n = 10]; GG >1 26% [n = 13]; infield 40% [n = 20]). At a median follow-up of 42 (13-73) mo, PCa was detected in 30 men (60%). Among all patients, 19 (38%) underwent salvage treatments (median [95% confidence interval] STFS 53 [44.3-61.7] mo). MFS and OS were 100% and 98%, respectively. The Expanded Prostate Cancer Index Composite-26 sexual domain decreased by 20.8 points (p = 0.372).

CONCLUSIONS

MRI/TRUS-guided focal HIFU therapy results in complete cancer ablation in only half of the treated patients after 1 yr, with further recurrences at medium-term follow-up. A decline of potency occurs in a subset of patients.

PATIENT SUMMARY

Focal image-guided high-intensity focused ultrasound therapy controls cancer in one of two patients. Its impact on urinary continence and erectile function is low.

Outcomes of partial gland ablation using high intensity focused ultrasound for prostate cancer

BACKGROUND

To evaluate the clinical and oncological outcomes of partial gland ablation (PGA) using high intensity focused ultrasound (HIFU) technique for the clinically unilateral prostate cancer.

METHODS

We performed a retrospective analysis for the 163 patients who treated by PGA for clinically unilateral prostate cancer. The PGA was performed using Focal one system with concurrent trans-urethral prostatectomy. The oncological and functional outcomes were evaluated as well as risk factors for remnant disease after PGA. Clinically significant cancer was defined as grade group ≥2.

RESULTS

Among the entire subjects, grade group 2 or greater was present at pre-treatment biopsy in 76.7%. Median follow-up time was 17 months and 60.1% of total subjects had follow-up biopsy at postoperative 1 year. There were 25 subjects (24.2%) with any cancer and 13 subjects (12.6%) with CS cancer at the follow-up biopsy. The preoperative age and number of positive cores at preoperative biopsy were significantly associated with positive results at follow-up biopsy. Incontinence which requires 2 or more pads per day was observed at 4 subjects (2.5%) postoperatively. There were no subjects who needed intensive care or experienced rectal complications.

CONCLUSION

The PGA with HIFU was safe and showed good preservation of functional outcomes as well as satisfactory oncological control. The remnant disease was observed in the 24.5% of patients who underwent follow-up biopsy in the present study. Thus, further prospective study is needed to evaluate oncological and functional outcomes of PGA with HIFU more accurately.

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.

Applications of Focused Ultrasound in the Treatment of Genitourinary Cancers

Simple Summary

Cancer is a prevalent disease globally, and conventional treatment options have been associated with substantial morbidity for patients. The unique acoustic properties and biological effects of focused ultrasound have been investigated for use as an alternative treatment option for various forms of cancer with lower associated morbidity than standard treatments. The objective of our review was to assess the current state and various applications of focused ultrasound for the treatment of genitourinary cancers, including prostate, kidney, bladder, penile, and testicular malignancies. Current research demonstrates that focused ultrasound-based focal therapy shows promise for the treatment of localized prostate and kidney cancer, and the effect of ultrasound on cell membranes may increase the efficacy of chemotherapeutics and radiotherapy. Focused ultrasound-based treatment modalities should continue to be investigated as an alternative or complementary treatment option for cancer patients.

Abstract

Traditional cancer treatments have been associated with substantial morbidity for patients. Focused ultrasound offers a novel modality for the treatment of various forms of cancer which may offer effective oncological control and low morbidity. We performed a review of PubMed articles assessing the current applications of focused ultrasound in the treatment of genitourinary cancers, including prostate, kidney, bladder, penile, and testicular cancer. Current research indicates that high-intensity focused ultrasound (HIFU) focal therapy offers effective short-term oncologic control of localized prostate and kidney cancer with lower associated morbidity than radical surgery. In addition, studies in mice have demonstrated that focused ultrasound treatment increases the accuracy of chemotherapeutic drug delivery, the efficacy of drug uptake, and cytotoxic effects within targeted cancer cells. Ultrasound-based therapy shows promise for the treatment of genitourinary cancers. Further research should continue to investigate focused ultrasound as an alternative cancer treatment option or as a complement to increase the efficacy of conventional treatments such as chemotherapy and radiotherapy.

High-Intensity Focused Ultrasound (HIFU) Focal Therapy for Localized Prostate Cancer with MRI-US Fusion Platform

Objective

The study aimed at investigating the outcome of prostate HIFU focal therapy using the MRI-US fusion platform for treatment localization and delivery.

Methods

It is a prospectively designed case series of HIFU focal therapy for localized prostate cancer. The inclusion criteria include clinical tumor stage ≤T2, visible index lesion on multiparametric MRI less than 20 mm in diameter, absence of Gleason 5 pattern on prostate biopsy, and PSA ≤ 20 ng/ml. HIFU focal therapy was performed in the conventional manner in the beginning 50% of the series, whereas the subsequent cases were performed with MRI-US fusion platform. The primary outcome was treatment failure rate which is defined by the need of salvage therapy. Secondary outcomes included tumor recurrence in follow-up biopsy, PSA change, perioperative complications, and postoperative functional outcomes.

Results

Twenty patients underwent HIFU focal ablation. HIFU on an MRI-US fusion platform had a trend of a longer total operative time than the conventional counterpart (124.2 min vs. 107.1 min, p=0.066). There was no difference in the mean ablation volume to lesion volume ratio between the two. The mean PSA percentage change from baseline to 6-month is more significant in the conventional group (63.3% vs. 44.6%, p=0.035). No suspicious lesion was seen at 6-month mpMRI in all 20 patients. Two patients, one from each group, eventually underwent radical treatment because of the presence of clinically significant prostate cancer in the form of out-of-field recurrences during follow-up biopsy. No significant difference was observed before and after HIFU concerning uroflowmetry, SF-12 score, and EPIC-26 score. It was observed that energy used per volume was positively correlated with PSA density of the patient (r = 0.6364, p=0.014).

Conclusion

In conclusion, HIFU with conventional or MRI-US fusion platform provided similar oncological and functional outcomes.