title: Risk factors for local recurrence in Wilms tumour and the potential influence of biopsy - the United Kingdom experience.
abstract: BACKGROUND
  The UKW3 trial compared biopsy/pre-operative chemotherapy versus immediate nephrectomy and afforded the opportunity to examine the influence of percutaneous retroperitoneal biopsy and other factors on local and distant relapse of Wilms tumour (WT).
  
  
  METHODS
  Patients with unilateral WT (stages I-IV) excluding metachronous relapse or early progressive disease were eligible. Metastatic and 'inoperable' tumours were biopsied electively. 'Local' was defined as relapse within the abdomen, except for liver metastases considered as 'distant' relapse, together with other haematogenous routes. Uni- and multivariable analyses estimated the risk factors for relapse.
  
  
  RESULTS
  Overall, 285/635 (44.9%) patients had a biopsy. With a median follow-up of 10.1 years, 35 (5.5%) patients experienced a 'local', 15 a combined (2.4%) and 60 (9.4%) a 'distant' relapse. On univariate analysis, biopsy, anaplasia and tumour size were associated with an increased risk of local relapse. On multivariable analysis, anaplasia and tumour size remained significant for local relapse whereas the elevated risk of biopsy (hazards ratio (HR) = 1.80: 95% confidence interval (CI) 0.97-3.32, p = 0.060) was marginal. Age, anaplasia, tumour size, lymph nodes metastases and stage, but not biopsy, were individually associated with increased risk of distant relapse but only age and anaplasia remained significant following multivariable analysis.
  
  
  CONCLUSIONS
  The UKW3 trial provides some reassurance that biopsy should not automatically lead to 'upstaging' of WT. Further assessment of this controversial area is required. Comparison of local relapse rates in a multinational trial in which the United Kingdom (UK) continued the practice of routinely biopsying all patients in contrast to the standard European approach will afford this opportunity and is planned.
authors.affiliation: Cancer Section, Developmental Biology & Cancer Programme, Institute of Child Health, University College London, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Irtan
authors.affiliation: Cancer Research UK & UCL Cancer Trials Centre, Cancer Institute, University College London, 90 Tottenham Court Road, London W1T 4TJ, UK.
authors.forename: M
authors.initials: M
authors.lastname: Jitlal
authors.affiliation: Cancer Section, Developmental Biology & Cancer Programme, Institute of Child Health, University College London, London, UK.
authors.forename: J
authors.initials: J
authors.lastname: Bate
authors.affiliation: Department of Paediatric Surgery, Leeds Teaching Hospitals NHS Trust, Leeds, UK.
authors.forename: M
authors.initials: M
authors.lastname: Powis
authors.affiliation: Department of Pathology, School of Medicine, Cardiff University, Cardiff, UK.
authors.forename: G
authors.initials: G
authors.lastname: Vujanic
authors.affiliation: Department of Pathology, Royal Manchester Children's Hospital, Manchester, UK.
authors.forename: A
authors.initials: A
authors.lastname: Kelsey
authors.affiliation: Department of Paediatric Surgery, Sheffield Children's Hospital, Sheffield, UK.
authors.forename: J
authors.initials: J
authors.lastname: Walker
authors.affiliation: Department of Paediatric Oncology, Oxford Radcliffe Hospitals NHS Trust, Oxford, UK.
authors.forename: C
authors.initials: C
authors.lastname: Mitchell
authors.affiliation: Children's Cancer and Leukaemia Group, University of Leicester, Leicester, UK.
authors.forename: D
authors.initials: D
authors.lastname: Machin
authors.affiliation: Cancer Section, Developmental Biology & Cancer Programme, Institute of Child Health, University College London, London, UK. Electronic address: k.pritchard-jones@ucl.ac.uk.
authors.forename: K
authors.initials: K
authors.lastname: Pritchard-Jones
mesh_terms: D000293:Adolescent; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D003609:Dactinomycin / Q000008:administration & dosage; D004317:Doxorubicin / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007668:Kidney / Q000187:drug effects / Q000473:pathology / Q000601:surgery; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery; D008297:Male; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local; D009392:Nephrectomy; D017063:Outcome Assessment, Health Care / Q000379:methods / Q000706:statistics & numerical data; D016016:Proportional Hazards Models; D012307:Risk Factors; D016019:Survival Analysis; D006113:United Kingdom; D014750:Vincristine / Q000008:administration & dosage; D009396:Wilms Tumor / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery
chemical_list: D003609:Dactinomycin; D014750:Vincristine; D004317:Doxorubicin
keywords: Local relapse; Percutaneous biopsy; Wilms tumour