title: The impact of routine surveillance screening with magnetic resonance imaging (MRI) to detect tumour recurrence in children with central nervous system (CNS) tumours: protocol for a systematic review and meta-analysis.
abstract: The aim of this study is to assess the impact of routine MRI surveillance to detect tumour recurrence in children with no new neurological signs or symptoms compared with alternative follow-up practices, including periodic clinical and physical examinations and the use of non-routine imaging upon presentation with disease signs or symptoms.
  
  
  
  Standard systematic review methods aimed at minimising bias will be employed for study identification, selection and data extraction. Ten electronic databases have been searched, and further citation searching and reference checking will be employed. Randomised and non-randomised controlled trials assessing the impact of routine surveillance MRI to detect tumour recurrence in children with no new neurological signs or symptoms compared to alternative follow-up schedules including imaging upon presentation with disease signs or symptoms will be included. The primary outcome is time to change in therapeutic intervention. Secondary outcomes include overall survival, surrogate survival outcomes, response rates, diagnostic yield per set of images, adverse events, quality of survival and validated measures of family psychological functioning and anxiety. Two reviewers will independently screen and select studies for inclusion. Quality assessment will be undertaken using the Cochrane Collaboration's tools for assessing risk of bias. Where possible, data will be summarised using combined estimates of effect for time to treatment change, survival outcomes and response rates using assumption-free methods. Further sub-group analyses and meta-regression models will be specified and undertaken to explore potential sources of heterogeneity between studies within each tumour type if necessary.
  
  
  
  Assessment of the impact of surveillance imaging in children with CNS tumours is methodologically complex. The evidence base is likely to be heterogeneous in terms of imaging protocols, definitions of radiological response and diagnostic accuracy of tumour recurrence due to changes in imaging technology over time. Furthermore, the delineation of tumour recurrence from either pseudo-progression or radiation necrosis after radiotherapy is potentially problematic and linked to the timing of follow-up assessments. However, given the current routine practice of MRI surveillance in the follow-up of children with CNS tumours in the UK and the resource implications, it is important to evaluate the cost-benefit profile of this practice.
  
  
  
  PROSPERO CRD42016036802.
authors: Cancer Research UK Clinical Trials Unit (CRCTU), Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK. c.main@bham.ac.uk.
authors: Caroline
authors: 0000-0002-9686-3438
authors: C
authors: Main
authors: Cancer Research UK Clinical Trials Unit (CRCTU), Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.
authors: Simon P
authors: SP
authors: Stevens
authors: Sir James Spence Institute of Child Health, Royal Victoria Infirmary, Newcastle-Upon-Tyne, UK.
authors: Simon
authors: S
authors: Bailey
authors: Centre for Reviews and Dissemination (CRD), University of York, York, UK.
authors: Robert
authors: R
authors: Phillips
authors: Alder Hey Children's NHS Foundation Trust, Liverpool, UK.
authors: Barry
authors: B
authors: Pizer
authors: Cancer Research UK Clinical Trials Unit (CRCTU), Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.
authors: Keith
authors: K
authors: Wheatley
authors: Cancer Research UK Clinical Trials Unit (CRCTU), Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.|Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.
authors: Pamela R
authors: PR
authors: Kearns
authors: Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.
authors: Martin
authors: M
authors: English
authors: Queen's Medical Centre, Nottingham University Hospitals' NHS Trust, Nottingham, UK.
authors: Sophie
authors: S
authors: Wilne
authors: Cancer Research UK Clinical Trials Unit (CRCTU), Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.
authors: Jayne S
authors: JS
authors: Wilson
mesh_terms: D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000000981:diagnostic imaging; D009423:Nervous System Neoplasms / Q000000981:diagnostic imaging*; D000078202:Systematic Reviews as Topic; D015201:Meta-Analysis as Topic
keywords: Central nervous system tumours; Children; Magnetic resonance imaging (MRI); Recurrent disease; Surveillance; Systematic review