title: High prevalence of early hypothalamic-pituitary damage in childhood brain tumor survivors: need for standardized follow-up programs.
abstract: BACKGROUND
  Childhood brain tumor survivors (CBTS) are at increased risk to develop endocrine disorders. Alerted by two cases who experienced delay in diagnosis of endocrine deficiencies within the first 5 years after brain tumor diagnosis, our aim was to investigate the current screening strategy and the prevalence of endocrine disorders in survivors of a childhood brain tumor outside of the hypothalamic-pituitary region, within the first 5 years after diagnosis.
  
  
  METHODS
  Firstly, we performed a retrospective study of 47 CBTS treated in our center, diagnosed between 2008 and 2012. Secondly, the literature was reviewed for the prevalence of endocrine disorders in CBTS within the first 5 years after diagnosis.
  
  
  RESULTS
  Of 47 CBTS eligible for evaluation, in 34% no endocrine parameters had been documented at all during follow up. In the other 66%, endocrine parameters had been inconsistently checked, with different parameters at different time intervals. In 19% of patients an endocrine disorder was found. At literature review 22 studies were identified. The most common reported endocrine disorder within the first 5 years after diagnosis was growth hormone deficiency (13-100%), followed by primary gonadal dysfunction (0-91%) central hypothyroidism (0-67%) and primary/subclinical hypothyroidism (range 0-64%).
  
  
  CONCLUSIONS
  Endocrine disorders are frequently seen within the first 5 years after diagnosis of a childhood brain tumor outside of the hypothalamic-pituitary region. Inconsistent endocrine follow up leads to unnecessary delay in diagnosis and treatment. Endocrine care for this specific population should be improved and standardized. Therefore, high-quality studies and evidence based guidelines are warranted.
authors.affiliation: Department of Pediatric Endocrinology, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Department of Pediatric Oncology, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Clement
authors.forename: Antoinette Y N Schouten-van
authors.initials: AY
authors.lastname: Meeteren
authors.forename: Leontien C M
authors.initials: LC
authors.lastname: Kremer
authors.forename: A S Paul
authors.initials: AS
authors.lastname: van Trotsenburg
authors.forename: Huib N
authors.initials: HN
authors.lastname: Caron
authors.forename: Hanneke M
authors.initials: HM
authors.lastname: van Santen
mesh_terms: D000293:Adolescent; D001932:Brain Neoplasms / Q000150:complications* / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D004700:Endocrine System Diseases / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006301:Health Services Needs and Demand / Q000592:standards*; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D011379:Prognosis; D012189:Retrospective Studies; D012196:Review Literature as Topic; D015996:Survival Rate; D017741:Survivors
keywords: adverse effects; brain tumor; childhood cancer survivor; deficiency; dysfunction; endocrine; growth hormone