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Lancet Oncology | 2012

Focal therapy for localised unifocal and multifocal prostate cancer: a prospective development study

Hashim U. Ahmed; Richard G. Hindley; Louise Dickinson; Alex Freeman; Alex Kirkham; Mahua Sahu; R. Scott; Clare Allen; Jan van der Meulen; Mark Emberton

Summary Background Radical whole-gland therapy can lead to significant genitourinary and rectal side-effects for men with localised prostate cancer. We report on whether selective focal ablation of unifocal and multifocal cancer lesions can reduce this treatment burden. Methods Men aged 45–80 years were eligible for this prospective development study if they had low-risk to high-risk localised prostate cancer (prostate specific antigen [PSA] ≤15 ng/mL, Gleason score ≤4 + 3, stage ≤T2), with no previous androgen deprivation or treatment for prostate cancer, and who could safely undergo multiparametric MRI and have a general anaesthetic. Patients received focal therapy using high-intensity focused ultrasound, delivered to all known cancer lesions, with a margin of normal tissue, identified on multiparametric MRI, template prostate-mapping biopsies, or both. Primary endpoints were adverse events (serious and otherwise) and urinary symptoms and erectile function assessed using patient questionnaires. Analyses were done on a per-protocol basis. This study is registered with ClinicalTrials.gov, number NCT00561314. Findings 42 men were recruited between June 27, 2007, and June 30, 2010; one man died from an unrelated cause (pneumonia) 3 months after treatment and was excluded from analyses. After treatment, one man was admitted to hospital for acute urinary retention, and another had stricture interventions requiring hospital admission. Nine men (22%, 95% CI 11–38) had self-resolving, mild to moderate, intermittent dysuria (median duration 5·0 days [IQR 2·5–18·5]). Urinary debris occurred in 14 men (34%, 95% CI 20–51), with a median duration of 14·5 days (IQR 6·0–16·5). Urinary tract infection was noted in seven men (17%, 95% CI 7–32). Median overall International Index of Erectile Function-15 (IIEF-15) scores were similar at baseline and at 12 months (p=0·060), as were median IIEF-15 scores for intercourse satisfaction (p=0·454), sexual desire (p=0·644), and overall satisfaction (p=0·257). Significant deteriorations between baseline and 12 months were noted for IIEF-15 erectile (p=0·042) and orgasmic function (p=0·003). Of 35 men with good baseline function, 31 (89%, 95% CI 73–97) had erections sufficient for penetration 12 months after focal therapy. Median UCLA Expanded Prostate Cancer Index Composite (EPIC) urinary incontinence scores were similar at baseline as and 12 months (p=0·045). There was an improvement in lower urinary tract symptoms, assessed by International Prostate Symptom Score (IPSS), between baseline and 12 months (p=0·026), but the IPSS-quality of life score showed no difference between baseline and 12 months (p=0·655). All 38 men with no baseline urinary incontinence were leak-free and pad-free by 9 months. All 40 men pad-free at baseline were pad-free by 3 months and maintained pad-free continence at 12 months. No significant difference was reported in median Trial Outcomes Index scores between baseline and 12 months (p=0·113) but significant improvement was shown in median Functional Assessment of Cancer Therapy (FACT)-Prostate (p=0·045) and median FACT-General scores (p=0·041). No histological evidence of cancer was identified in 30 of 39 men biopsied at 6 months (77%, 95% CI 61–89); 36 (92%, 79–98) were free of clinically significant cancer. After retreatment in four men, 39 of 41 (95%, 95% CI 83–99) had no evidence of disease on multiparametric MRI at 12 months. Interpretation Focal therapy of individual prostate cancer lesions, whether multifocal or unifocal, leads to a low rate of genitourinary side-effects and an encouraging rate of early absence of clinically significant prostate cancer. Funding Medical Research Council (UK), Pelican Cancer Foundation, and St Peters Trust.


Nature Reviews Clinical Oncology | 2009

Is it time to consider a role for MRI before prostate biopsy

Hashim U. Ahmed; Alex Kirkham; Manit Arya; R.O. Illing; Alex Freeman; Clare Allen; Mark Emberton

The use of MRI in prostate cancer management is controversial and current guidelines underplay its role. Technological advances over the past 5 years, however, demand a re-evaluation of this position. In this article, we propose an increased use of MRI, not only in those with a diagnosis of prostate cancer but also for men before a prostate biopsy. The use of MRI before a biopsy can serve as a triage test in men with raised serum prostate-specific antigen levels, in order to select those for biopsy with significant cancer that requires treatment. This strategy could avoid biopsy, and hence unnecessary treatment, in those with no disease or insignificant cancer. In addition, avoidance of postbiopsy artifact caused by hemorrhage will lead to better local staging accuracy, while determining more accurately the disease burden. This approach could improve risk stratification by selecting those who require adjuvant therapy or dose escalation. Furthermore, MRI evaluation of cancer burden could be important in active surveillance regimens to select those needing intervention.


The Journal of Urology | 2011

Focal Therapy for Localized Prostate Cancer: A Phase I/II Trial

Hashim U. Ahmed; Alex Freeman; Alex Kirkham; M. Sahu; R. Scott; Clare Allen; J van der Meulen; Mark Emberton

PURPOSE Men with localized prostate cancer currently face a number of treatment options that treat the entire prostate. These can cause significant sexual and urinary side effects. Focal therapy offers a novel strategy that targets the cancer rather than the prostate in an attempt to preserve tissue and function. MATERIALS AND METHODS A prospective, ethics committee approved trial was conducted to determine the side effects of focal therapy using high intensity focused ultrasound. Multiparametric magnetic resonance imaging (T2-weighted, dynamic contrast enhanced, diffusion-weighted) and template transperineal prostate mapping biopsies were used to identify unilateral disease. Genitourinary side effects and quality of life outcomes were assessed using validated questionnaires. Posttreatment biopsies were performed at 6 months and followup was completed to 12 months. RESULTS A total of 20 men underwent high intensity focused ultrasound hemiablation. Mean age was 60.4 years (SD 5.4, range 50 to 70) with mean prostate specific antigen 7.3 ng/ml (SD 2.8, range 3.4 to 11.8). Of the men 25% had low risk and 75% had intermediate risk cancer. Return of erections sufficient for penetrative sex occurred in 95% of men (19 of 20). In addition, 90% of men (18 of 20) were pad-free, leak-free continent while 95% were pad-free. Mean prostate specific antigen decreased 80% to 1.5 ng/ml (SD 1.3) at 12 months. Of the men 89% (17 of 19, 1 refused biopsy) had no histological evidence of any cancer, and none had histological evidence of high volume or Gleason 7 or greater cancer in the treated lobe. In addition, 89% of men achieved the trifecta status of pad-free, leak-free continence, erections sufficient for intercourse and cancer control at 12 months. CONCLUSIONS Our results appear sufficiently promising to support the further evaluation of focal therapy as a strategy to decrease some of the harms and costs associated with standard whole gland treatments.


The Journal of Urology | 2013

Transperineal Magnetic Resonance Image Targeted Prostate Biopsy Versus Transperineal Template Prostate Biopsy in the Detection of Clinically Significant Prostate Cancer.

Veeru Kasivisvanathan; Robert Dufour; Caroline M. Moore; Hashim U. Ahmed; Mohamed Abd-Alazeez; Susan Charman; Alex Freeman; Clare Allen; Alex Kirkham; Jan van der Meulen; Mark Emberton

PURPOSE Multiparametric magnetic resonance imaging can be used to guide prostate biopsy by targeting biopsies to areas in the prostate at high risk for cancer. We compared the detection of clinically significant and insignificant cancer by transperineal magnetic resonance imaging targeted biopsy and transperineal template guided prostate biopsy. MATERIALS AND METHODS A total of 182 men with a lesion suspicious for cancer on multiparametric magnetic resonance imaging underwent transperineal magnetic resonance imaging targeted biopsy using a cognitive registration technique, followed by systematic transperineal template guided prostate biopsy. The primary outcome was the detection rate of clinically significant prostate cancer. Clinical significance was defined using maximum cancer core length 4 mm or greater and/or Gleason grade 3 + 4 or greater (University College London definition 2). We secondarily evaluated other commonly used thresholds of clinically significant disease, including maximum cancer core length 6 mm or greater and/or Gleason grade 4 + 3 or greater, maximum cancer core length 3 mm or greater and/or Gleason grade 3 + 4 or greater, and maximum cancer core length 2 or greater mm and/or Gleason grade 3 + 4 or greater. Strategies were statistically compared with the McNemar test. RESULTS Mean ± SD patient age was 63.3 ± 7.2 years. Median prostate specific antigen was 6.7 ng/ml (IQR 4.7-10.0). Clinically significant cancer was detected by magnetic resonance imaging targeted biopsy and template guided prostate biopsy in 103 (57%) and 113 of the 182 men (62%) (p = 0.174), and clinically insignificant cancer was detected in 17 (9.3%) and 31 (17.0%), respectively (p = 0.024). CONCLUSIONS Prostate biopsy targeted to suspicious lesions on multiparametric magnetic resonance imaging has encouraging rates of detection of clinically significant cancer while also decreasing the detection rate of clinically insignificant cancer. This is achieved with fewer biopsy cores than for systematic template guided biopsy. Further prospective, multicenter, comparative trials of the performance of targeting strategies are needed to consider magnetic resonance imaging targeted biopsy an alternative to conventional systematic biopsy.


Nature Reviews Clinical Oncology | 2007

Will focal therapy become a standard of care for men with localized prostate cancer

Hashim U. Ahmed; Doug Pendsé; R.O. Illing; Clare Allen; Jan van der Meulen; Mark Emberton

The current treatment choice for men with localized prostate cancer lies between active surveillance and radical therapy. The difference between these two extremes of care is 5% in terms of cancer-related absolute mortality at 8 years. It is generally accepted that this small difference will decrease for men diagnosed in the prostate-specific-antigen era. Radical therapy is associated with considerable adverse effects (e.g. incontinence, impotence, rectal problems) because it treats the whole gland, and damages surrounding structures in up to half of men. Men are being diagnosed at a younger age with lower-risk disease, and many have unifocal or unilateral disease. We propose a new concept whereby only the tumor focus and a margin of normal tissue are treated. This paradigm might decrease adverse effects whilst, at the same time, retaining effective cancer control. The arguments for and against active surveillance and radical therapy are reviewed in this article, with focal therapy presented as a means for bridging these two approaches.


Radiology | 2013

Multiparametric MR Imaging for Detection of Clinically Significant Prostate Cancer: A Validation Cohort Study with Transperineal Template Prostate Mapping as the Reference Standard

N. Arumainayagam; Hashim U. Ahmed; Caroline M. Moore; Alex Freeman; Clare Allen; Sa Sohaib; Alex Kirkham; J van der Meulen; Mark Emberton

PURPOSE To evaluate the diagnostic performance of multiparametric (MP) magnetic resonance (MR) imaging for prostate cancer detection by using transperineal template prostate mapping (TTPM) biopsies as the reference standard and to determine the potential ability of MP MR imaging to identify clinically significant prostate cancer. MATERIALS AND METHODS Institutional review board exemption was granted by the local research ethics committee for this retrospective study. Included were 64 men (mean age, 62 years [range, 40-76]; mean prostate-specific antigen, 8.2 ng/mL [8.2 μg/L] [range, 2.1-43 ng/mL]), 51 with biopsy-proved cancer and 13 suspected of having clinically significant cancer that was biopsy negative or without prior biopsy. MP MR imaging included T2-weighted, dynamic contrast-enhanced and diffusion-weighted imaging (1.5 T, pelvic phased-array coil). Three radiologists independently reviewed images and were blinded to results of biopsy. Two-by-two tables were derived by using sectors of analysis of four quadrants, two lobes, and one whole prostate. Primary target definition for clinically significant disease necessary to be present within a sector of analysis on TTPM for that sector to be deemed positive was set at Gleason score of 3+4 or more and/or cancer core length involvement of 4 mm or more. Sensitivity, negative predictive value, and negative likelihood ratio were calculated to determine ability of MP MR imaging to rule out cancer. Specificity, positive predictive value, positive likelihood ratio, accuracy (overall fraction correct), and area under receiver operating characteristic curves were also calculated. RESULTS Twenty-eight percent (71 of 256) of sectors had clinically significant cancer by primary endpoint definition. For primary endpoint definition (≥ 4 mm and/or Gleason score ≥ 3+4), sensitivity, negative predictive value, and negative likelihood ratios were 58%-73%, 84%-89%, and 0.3-0.5, respectively. Specificity, positive predictive value, and positive likelihood ratios were 71%-84%, 49%-63%, and 2.-3.44, respectively. Area under the curve values were 0.73-0.84. CONCLUSION Results of this study indicate that MP MR imaging has a high negative predictive value to rule out clinically significant prostate cancer and may potentially have clinical use in diagnostic pathways of men at risk.


BJUI | 2013

TOOKAD® Soluble vascular‐targeted photodynamic (VTP) therapy: determination of optimal treatment conditions and assessment of effects in patients with localised prostate cancer

A.R. Azzouzi; Eric Barret; Caroline M. Moore; Arnaud Villers; Clare Allen; Avigdor Scherz; Gordon Muir; Michel de Wildt; Neil J. Barber; Souhil Lebdai; Mark Emberton

To evaluate the optimal treatment conditions and effects of TOOKAD® Soluble vascular‐targeted photodynamic (VTP) therapy in patients with localised prostate cancer. To evaluate the safety and quality of life after TOOKAD® Soluble VTP treatment in patients with localised prostate cancer.


Journal of Magnetic Resonance Imaging | 2013

Scoring systems used for the interpretation and reporting of multiparametric MRI for prostate cancer detection, localization, and characterization: could standardization lead to improved utilization of imaging within the diagnostic pathway?

Louise Dickinson; Hashim U. Ahmed; Clare Allen; Jelle O. Barentsz; Brendan Carey; Jurgen J. Fütterer; Stijn W.T.P.J. Heijmink; Peter Hoskin; Alex Kirkham; Anwar R. Padhani; Raj Persad; P. Puech; Shonit Punwani; Aslam Sohaib; Bertrand Tombal; Arnauld Villers; Mark Emberton

Multiparametric magnetic resonance imaging (mpMRI) is increasingly being used earlier in the prostate cancer diagnostic pathway in order to detect and localize disease. Its results can be used to help decide on the indication, type, and localization of a prostate biopsy for cancer diagnosis. In addition, mpMRI has the potential to contribute information on the characterization, or aggressiveness, of detected cancers including tumor progression over time. There is considerable variation in the way results of different MRI sequences are reported. We conducted a review of scoring systems that have been used in the detection and characterization of prostate cancer. This revealed that existing scoring and reporting systems differ in purpose, scale, and range. We evaluate these differences in this review. This first step in collating all methods of scoring and reporting mpMRI will ultimately lead to consensus approaches to develop a standardized reporting scheme that can be widely adopted and validated to ensure comparability of research outputs and optimal clinical practice. J. Magn. Reson. Imaging 2013;37:48–58.


BJUI | 2008

The feasibility and safety of high‐intensity focused ultrasound as salvage therapy for recurrent prostate cancer following external beam radiotherapy

Evangelos Zacharakis; Hashim U. Ahmed; A. Ishaq; R. Scott; Rowland O. Illing; Alex Freeman; Clare Allen; Mark Emberton

To investigate the use of minimally invasive high‐intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT).


Prostate Cancer and Prostatic Diseases | 2014

Initial assessment of safety and clinical feasibility of irreversible electroporation in the focal treatment of prostate cancer

Massimo Valerio; Hashim U. Ahmed; Louise Dickinson; Lee E. Ponsky; Ron Shnier; Clare Allen; Mark Emberton

Background:To evaluate the safety and clinical feasibility of focal irreversible electroporation (IRE) of the prostate.Methods:We assessed the toxicity profile and functional outcomes of consecutive patients undergoing focal IRE for localised prostate cancer in two centres. Eligibility was assessed by multi-parametric magnetic resonance imaging (mpMRI) and targeted and/or template biopsy. IRE was delivered under transrectal ultrasound guidance with two to six electrodes positioned transperineally within the cancer lesion. Complications were recorded and scored accordingly to the NCI Common Terminology Criteria for Adverse Events; the functional outcome was physician reported in all patients with at least 6 months follow-up. A contrast-enhanced MRI 1 week after the procedure was carried out to assess treatment effect with a further mpMRI at 6 months to rule out evidence of residual visible cancer.Results:Overall, 34 patients with a mean age of 65 years (s.d.=±6) and a median PSA of 6.1 ng ml−1 (interquartile range (IQR)= 4.3–7.7) were included. Nine (26%), 24 (71%) and 1 (3%) men had low, intermediate and high risk disease, respectively (D’Amico criteria). After a median follow-up of 6 months (range 1–24), 12 grade 1 and 10 grade 2 complications occurred. No patient had grade >/= 3 complication. From a functional point of view, 100% (24/24) patients were continent and potency was preserved in 95% (19/20) men potent before treatment. The volume of ablation was a median 12 ml (IQR=5.6–14.5 ml) with the median PSA after 6 months of 3.4 ng ml−1 (IQR=1.9–4.8 ng ml−1). MpMRI showed suspicious residual disease in six patients, of whom four (17%) underwent another form of local treatment.Conclusions:Focal IRE has a low toxicity profile with encouraging genito-urinary functional outcomes. Further prospective development studies are needed to confirm the functional outcomes and to explore the oncological potential.

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Mark Emberton

University College London

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Alex Kirkham

University College Hospital

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Alex Freeman

University College Hospital

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Shonit Punwani

University College London

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M. Emberton

London North West Healthcare NHS Trust

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R.O. Illing

University College London

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