title: Rare malignant pediatric tumors registered in the German Childhood Cancer Registry 2001-2010.
abstract: BACKGROUND
  The German Childhood Cancer Registry (GCCR) annually registers approximately 2,000 children diagnosed with a malignant disease (completeness of registration >95%). While most pediatric cancer patients are diagnosed and treated according to standardized cooperative protocols of the German Society for Pediatric Oncology and Hematology (GPOH), patients with rare tumors are at risk of not being integrated in the network including trials and reference centers.
  
  
  METHODS
  A retrospective analysis of all rare extracranial solid tumors reported to the GCCR 2001-2010 (age <18 years) was undertaken using a combination of the International Classification of Childhood Cancer (ICCC-3) and the International Classification of Diseases-Oncology (ICD-O-3). Tumors accounting for <0.3% of all malignancies were defined as rare (approx. 6 cases/year and registered malignancy).
  
  
  RESULTS
  According to this definition 1,189 rare extracranial solid tumors (18.2% of all malignant extracranial solid tumors) were registered, among these 232 patients (19.5% of rare tumor cases), were not included in preexisting GPOH studies/registries. Within 10 years, the number of registered non-GPOH-trial patients with a rare tumor increased.
  
  
  CONCLUSIONS
  Though most of the GCCR-registered patients with rare malignant tumors are treated within GPOH trials, there is a considerable number of patients that have been diagnosed and treated outside the structures of the GPOH. These patients should be reported to the recently founded German Pediatric Rare Tumor Registry (STEP). Active data accrual and the development of appropriate structures will allow for better registration and improvement of medical care in these patients.
authors.affiliation: Pediatric Oncology and Hematology-Children's University Hospital, Erlangen, Germany.
authors.forename: Ines B
authors.initials: IB
authors.lastname: Brecht
authors.forename: Claudia
authors.initials: C
authors.lastname: Bremensdorfer
authors.forename: Dominik T
authors.initials: DT
authors.lastname: Schneider
authors.forename: Michael C
authors.initials: MC
authors.lastname: Frühwald
authors.forename: Sonja
authors.initials: S
authors.lastname: Offenmüller
authors.forename: Rolf
authors.initials: R
authors.lastname: Mertens
authors.forename: Peter
authors.initials: P
authors.lastname: Vorwerk
authors.forename: Ewa
authors.initials: E
authors.lastname: Koscielniak
authors.forename: Stefan S
authors.initials: SS
authors.lastname: Bielack
authors.forename: Martin
authors.initials: M
authors.lastname: Benesch
authors.forename: Barbara
authors.initials: B
authors.lastname: Hero
authors.forename: Norbert
authors.initials: N
authors.lastname: Graf
authors.forename: Dietrich
authors.initials: D
authors.lastname: von Schweinitz
authors.forename: Peter
authors.initials: P
authors.lastname: Kaatsch
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008297:Male; D009369:Neoplasms / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D035583:Rare Diseases / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D012042:Registries; D012189:Retrospective Studies
keywords: cancer registry; epidemiology; orphan disease; pediatric oncology; rare tumors; sarcomas