title: Where are the opportunities for an earlier diagnosis of primary intracranial tumours in children and young adults?
abstract: BACKGROUND
  Childhood brain tumours have some of the longest time to diagnosis. A timely diagnosis may have a role in reducing anxiety in waiting for a diagnosis and subsequent morbidity and mortality. We investigated where the opportunities for an earlier diagnosis were, and for which anatomical locations this strategy will most likely to be effective.
  
  
  METHODS
  A record-linkage cohort study of patients diagnosed aged 0-24 years with a primary intracranial tumour between 1989 and 2006 in England, using records from the National Cancer Registry linked to hospital admission records from Hospital Episode Statistics (HES, 1997-2006) and primary care consultation records from Clinical Practice Research Datalink (CPRD, 1989-2006). Relevant neurological presentations were extracted from HES and CPRD. Temporal changes in presentation rates were estimated in generalised additive models.
  
  
  RESULTS
  Frequency of presentation began to increase six months before diagnosis in primary care and three months before diagnosis in hospital. Supratentorial and midline tumours had the longest presentation history before diagnosis. Peri-ventricular tumours presented frequently in hospital (rate ratio = 1.29 vs supratentorial tumours; 95% CI = 1.12-1.48) or as an emergency (1.24; 1.01-1.51), and in primary care (1.12; 0.62-1.85).
  
  
  CONCLUSIONS
  Opportunities for an earlier diagnosis are greater in supratentorial, midline or cranial nerve tumours, which have a longer presentation history than peri-ventricular, cerebellar or brainstem tumours. Common features before diagnosis include headache, convulsions, and growth or endocrine disorders. Focal neurological deficits are uncommon and emerge late in the pre-diagnosis period.
authors.affiliation: Cancer Research UK Cancer Survival Group, Department of Non-communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom. Electronic address: thomas.chu@lshtm.ac.uk.
authors.forename: Thomas P C
authors.initials: TPC
authors.lastname: Chu
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Road, Oxford OX3 7LD, United Kingdom.
authors.forename: Anjali
authors.initials: A
authors.lastname: Shah
authors.affiliation: Children's Brain Tumour Research Centre, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Walker
authors.affiliation: Cancer Research UK Cancer Survival Group, Department of Non-communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom.
authors.forename: Michel P
authors.initials: MP
authors.lastname: Coleman
mesh_terms: D000293:Adolescent; D001932:Brain Neoplasms / Q000175:diagnosis*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D055088:Early Detection of Cancer / Q000706:statistics & numerical data*; D004700:Endocrine System Diseases / Q000150:complications; D004739:England; D005260:Female; D006261:Headache / Q000150:complications; D006760:Hospitalization; D006801:Humans; D007223:Infant; D008297:Male; D009422:Nervous System Diseases / Q000150:complications; D011320:Primary Health Care / Q000379:methods; D012042:Registries; D012640:Seizures / Q000150:complications; D013997:Time Factors; D055815:Young Adult
keywords: Brain neoplasms; Early diagnosis; Epidemiology; Oncology; Signs and symptoms; Symptom assessment