title: Focal Ablation Targeted to the Index Lesion in Multifocal Localised Prostate Cancer: a Prospective Development Study.
abstract: BACKGROUND
  Although localised prostate cancer is multifocal in most instances, the index lesion might be responsible for disease progression.
  
  
  OBJECTIVE
  To determine the early genitourinary functional and cancer control outcomes of index lesion ablation.
  
  
  METHODS
  This was a single-centre prospective development study in which 56 men were treated (July 2009-January 2011). The mean age was 63.9 yr (standard deviation 5.8) and median prostate-specific antigen (PSA) was 7.4 ng/ml (interquartile range [IQR] 5.6-9.5). There were seven (12.5%) low-risk, 47 (83.9%) intermediate-risk, and two (3.6%) high-risk cancers.
  
  
  METHODS
  Multiparametric magnetic resonance imaging (mpMRI) and prostate biopsies to localise disease, followed by index lesion ablation using high-intensity focused ultrasound.
  
  
  METHODS
  Primary outcomes were genitourinary side effects measured using validated questionnaires. Secondary outcomes included absence of clinically significant disease at 12 mo.
  
  
  CONCLUSIONS
  The composite of leak-free, pad-free continence, and erections sufficient for penetration decreased from a baseline frequency of 40/56 (71.4%) to 33/56 (58.9%) at 12 mo. Pad-free and leak-free, pad-free continence was preserved in 48/52 (92.3%) and 46/50 (92.0%) patients, respectively. Erections sufficient for intercourse were preserved in 30/39 (76.9%) patients. The median PSA nadir decreased to 2.4 ng/ml (IQR 1.6-4.1). At 12 mo, 42/52 (80.8%) patients had histological absence of clinically significant cancer and 85.7% (48/56) had no measurable prostate cancer (biopsy and/or mpMRI). Two (3.6%) patients had clinically significant disease in untreated areas not detected at baseline. The main study limitation is the short follow-up duration.
  
  
  CONCLUSIONS
  Index lesion ablation had low rates of genitourinary side effects and acceptable short-term absence of clinically significant cancer. Comparative effectiveness trials are required to assess cancer control outcomes against radical therapy.
  
  
  RESULTS
  In this study we looked at whether it is possible to treat the largest and highest-grade tumour in men who have more than one known prostate tumour. We show that the side effects of targeted ablation were low, with acceptable rates of early cancer control. Larger studies with longer follow-up are needed.
  
  
  BACKGROUND
  NCT00988130.
authors: Division of Surgery and Interventional Science, University College London, London, UK; Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK. Electronic address: hashim.ahmed@ucl.ac.uk.
authors: Hashim U
authors: HU
authors: Ahmed
authors: Division of Surgery and Interventional Science, University College London, London, UK; Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Louise
authors: L
authors: Dickinson
authors: Department of Health Services Research and Policy, The London School of Hygiene and Tropical Medicine, London, UK; Clinical Effectiveness Unit, Royal College of Surgeons of England, London, UK.
authors: Susan
authors: S
authors: Charman
authors: Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Shraddha
authors: S
authors: Weir
authors: Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Neil
authors: N
authors: McCartan
authors: Department of Urology, Hampshire Hospitals NHS Foundation Trust, Basingstoke, UK.
authors: Richard G
authors: RG
authors: Hindley
authors: Department of Histopathology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Alex
authors: A
authors: Freeman
authors: Department of Radiology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Alex P
authors: AP
authors: Kirkham
authors: Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Mahua
authors: M
authors: Sahu
authors: Division of Surgery and Interventional Science, University College London, London, UK.
authors: Rebecca
authors: R
authors: Scott
authors: Department of Radiology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Clare
authors: C
authors: Allen
authors: Department of Health Services Research and Policy, The London School of Hygiene and Tropical Medicine, London, UK; Clinical Effectiveness Unit, Royal College of Surgeons of England, London, UK.
authors: Jan
authors: J
authors: Van der Meulen
authors: Division of Surgery and Interventional Science, University College London, London, UK; Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK.
authors: Mark
authors: M
authors: Emberton
mesh_terms: D055011:Ablation Techniques; D000368:Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000473:pathology / Q000601:surgery*
keywords: Clinically significant; Focal therapy; Index lesion; Multiparametric magnetic resonance imaging; Prostate cancer; Transperineal template biopsy