Prospective Multicenter Phase II Study on Focal Therapy (Hemiablation) of the Prostate with High Intensity Focused Ultrasound

Prostate cancer treatment by the latest focal HIFU device with MRI/TRUS-fusion control biopsies: A prospective evaluation

OBJECTIVES

Magnetic resonance imaging/transrectal ultrasound (MRI/TRUS) fusion-guided focal high intensity focused ultrasound (HIFU) therapy of the prostate has recently been developed as a selective HIFU-therapy technique to enable targeted ablation of prostate cancer. Here we report a series of patients treated with focal HIFU therapy, discuss its potential pitfalls, and address controversies concerning the indications.

MATERIALS AND METHODS

This single-center prospective study reports outcomes of patients treated from September 2014 to March 2016. Follow-up was a minimum of 12 months. MRI/TRUS-fusion-guided HIFU was performed under general anesthesia using the Focal One® device (EDAP, France). A control biopsy at 12 months was taken using the MRI/TRUS-fusion biopsy platform Artemis™ (Eigen, California) combining targeted and systematic cores. Prostate-specific antigen (PSA) changes from baseline, patient-reported outcome measures, and complications using the Clavien-Dindo classification system are also reported.

RESULTS

Twenty-four patients (PSA < 10 ng/ml, n = 17 Gleason 3+3, n = 7 Gleason 3+4) with either unifocal or bifocal prostate imaging reporting and data system (PI-RADS) 3-5 lesions (n = 19) or without a PI-RADS lesion (n = 5) were treated. Nineteen patients underwent focal HIFU, five patients zonal HIFU. Of the 20 patients that had biopsies at 12 months, 8 patients had a positive biopsy within the ablation zone (overall cancer free rate: 60%). Using different definitions of clinically significant cancer, the cancer-free rate for the ablation zone varies between 75% and 95%. Four of the eight patients (all persistent Gleason 3+4 or upgrading to 4+3) underwent a radical whole gland salvage therapy. Patient-reported outcome measures showed no significant decrease in urinary continence (expanded prostate cancer index composite -26 urinary incontinence: P = 0.080), but there was a reduction in potency (International index of erectile function in preoperatively potent patients: median decrease of 2 points to a median of 19 points at 12 months; 95% confidence interval: 15.79-22.21; P = 0.044). Only one complication > grade II occurred.

CONCLUSIONS

Targeted MRI/TRUS fusion-guided focal HIFU allows local tumor ablation, but is not free from limitations. The procedure has good functional outcomes and a quick recovery. Multicenter trials with more patients are required to determine the procedure´s role in the prostate cancer therapy algorithm.

Primary cryotherapy for localised or locally advanced prostate cancer

BACKGROUND

Traditionally, radical prostatectomy and radiotherapy with or without androgen deprivation therapy have been the main treatment options to attempt to cure men with localised or locally advanced prostate cancer. Cryotherapy is an alternative option for treatment of prostate cancer that involves freezing of the whole prostate (whole gland therapy) or only the cancer (focal therapy), but it is unclear how effective this is in comparison to other treatments.

OBJECTIVES

To assess the effects of cryotherapy (whole gland or focal) compared with other interventions for primary treatment of clinically localised (cT1-T2) or locally-advanced (cT3) non-metastatic prostate cancer.

SEARCH METHODS

We updated a previously published Cochrane Review by performing a comprehensive search of multiple databases (CENTRAL, MEDLINE, EMBASE), clinical trial registries (ClinicalTrials.gov, World Health Organization International Clinical Trials Registry Platform) and a grey literature repository (Grey Literature Report) up to 6 March 2018. We also searched the reference lists of other relevant publications and conference proceedings. We applied no language restrictions.

SELECTION CRITERIA

We included randomised or quasi-randomised trials comparing cryotherapy to other interventions for the primary treatment of prostate cancer.

DATA COLLECTION AND ANALYSIS

Two independent reviewers screened the literature, extracted data, and assessed risk of bias. We performed statistical analyses using a random-effects model and interpreted them according to the Cochrane Handbook for Systematic Reviews of Interventions. We rated the quality of evidence (QoE) according to the GRADE approach.

MAIN RESULTS

We included only one comparison of whole gland cryotherapy versus external beam radiotherapy, which was informed by two trials with a total of 307 randomised participants. The median age of the included studies was around 70 years. The median follow-up of included studies ranged from 100 to 105 months.Primary outcomes: we are uncertain about the effect of whole gland cryotherapy compared to radiation therapy on time to death from prostate cancer; hazard ratio (HR) of 1.00 (95% confidence interval (CI) 0.11 to 9.45; 2 trials, 293 participants; very low QoE); this would correspond to zero fewer death from prostate cancer per 1000 men (95% CI 85 fewer to 520 more). We are equally uncertain about the effect of quality of life-related urinary function and bowel function (QoL) at 36 months using the UCLA-Prostate Cancer Index score for which higher values (range: 0 to 100) reflect better quality of life using minimal clinically important differences (MCID) of 8 and 7 points, respectively; mean difference (MD) of 4.4 (95% CI -6.5 to 15.3) and 4.0 (95% CI -73.96 to 81.96), respectively (1 trial, 195 participants; very low QoE). We are also uncertain about sexual function-related QoL using a MCID of 8 points; MD of -20.7 (95% CI -36.29 to -5.11; 1 trial, 195 participants; very low QoE). Lastly, we are uncertain of the risk for major adverse events; risk ratio (RR): 0.91 (95% CI 0.47 to 1.78; 2 trials, 293 participants; very low QoE); this corresponds to 10 fewer major adverse events per 1000 men (95% CI 58 fewer to 86 more).

SECONDARY OUTCOMES

we are very uncertain about the effects of cryotherapy on time to death from any cause (HR 0.99, 95% CI 0.05 to 18.79; 2 trials, 293 participants; very low QoE), and time to biochemical failure (HR 2.15, 95% CI 0.07 to 62.12; 2 trials, 293 participants; very low QoE). Rates of secondary interventions for treatment failure and minor adverse events were either not reported in the trials, or the data could not be used for analyses.We found no trials that compared whole gland cryotherapy or focal cryotherapy to other treatment forms such as radical surgery, active surveillance, watchful waiting or other forms of radiotherapy.

AUTHORS' CONCLUSIONS

Based on very low quality evidence, primary whole gland cryotherapy has uncertain effects on oncologic outcomes, QoL, and major adverse events compared to external beam radiotherapy. Reasons for downgrading the QoE included serious study limitations, indirectness due to the use of lower doses of radiation in the comparison group than currently recommended, and serious or very serious imprecision.

Which technology to select for primary focal treatment of prostate cancer?-European Section of Urotechnology (ESUT) position statement

BACKGROUND

With growing interest in focal therapy (FT) of prostate cancer (PCa) there is an increasing armamentarium of treatment modalities including high-intensity focused ultrasound (HIFU), cryotherapy, focal laser ablation (FLA), irreversible electroporation (IRE), vascular targeted photodynamic therapy (VTP), focal brachytherapy (FBT) and stereotactic ablative radiotherapy (SABR). Currently there are no clear recommendations as to which of these technologies are appropriate for individual patient characteristics. Our intention was to review the literature for special aspects of the different technologies that might be of advantage depending on individual patient and tumour characteristics.

METHODS

The current literature on FT was screened for the following factors: morbidity, repeatability, tumour risk category, tumour location, tumour size and prostate volume and anatomical issues. The ESUT expert panel arrived at consensus regarding a position statement on a structured pathway for available FT technologies based on a combination of the literature and expert opinion.

RESULTS

Side effects were low across different studies and FT modalities with urinary continence rates of 90-100% and erectile dysfunction between 5 and 52%. Short to medium cancer control based on post-treatment biopsies were variable between ablative modalities. Expert consensus suggested that posterior lesions are better amenable to FT using HIFU. Cryotherapy provides best possible outcomes for anterior tumours. Apical lesions, when treated with FBT, may yield the least urethral morbidity.

CONCLUSIONS

Further prospective trials are required to assess medium to long term disease control of different ablative modalities for FT. Amongst different available FT modalities our ESUT expert consensus suggests that some may be better for diffe`rent tumour locations. Tumour risk, tumour size, tumour location, and prostate volume are all important factors to consider and might aid in designing future FT trials.

Focal Ablation of Prostate Cancer

The challenge to the urology community is to reduce the risks of screening and treatment by reducing the number of men undergoing unnecessary biopsy and whole-gland curative treatment of low-risk disease. There is compelling evidence that focal ablation of prostate cancer is truly minimally invasive and offers major functional advantages over whole-gland treatment.