title: Prevalence of subependymal giant cell tumors in patients with tuberous sclerosis and a review of the literature.
abstract: OBJECTIVE
  To investigate the prevalence of subependymal giant cell ependymomas (SEGA) in patients with tuberous sclerosis complex (TSC).
  
  
  METHODS
  We performed a retrospective cross-sectional study in a cohort of 285 patients with known TSC. Institutional review board approval was obtained. We included all 214 TSC-patients who had received a contrast-enhanced computed tomography (CT) scan of the brain. The most recent scan was evaluated for SEGA and presence of hydrocephalus. Additionally, a literature search was performed, and pooled estimates of SEGA prevalence in TSC were calculated. We used descriptive statistics, two sample t-test, chi-squared-test, and meta-analysis as appropriate.
  
  
  RESULTS
  Computed tomography showed radiological evidence of SEGA in 43 of the 214 TSC-patients (20%); 23 of 105 men (22%) and 20 of 109 women (18%; P = .52). Average maximum tumor size was 11.4 mm (range, 4-29 mm). Patients with SEGA (mean, 31 years; range, 16-58 years) were on average younger than patients without SEGA (mean, 37 years; range, 10-72 years; P = 0.007). No association between tumor size and patient age was detected. Nine patients had bilateral SEGA. Hydrocephalus was present in six of the 43 patients (14%). Meta-analysis of reported prevalence and our current study showed that studies using radiological evidence to diagnose SEGA gave a higher pooled estimate of the prevalence of SEGA in TSC (0.16; 95% CI: 0.12, 0.21) than studies using mainly histopathological evidence of SEGA (0.09; 95% CI: 0.07, 0.12).
  
  
  CONCLUSIONS
  In our cohort, CT demonstrated evidence of SEGA in 20% of TSC-patients. Prevalence of SEGA in TSC is higher in studies using radiological evidence to diagnose SEGA than in studies using histopathological evidence.
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. miraude@gmail.com
authors.forename: M E A P M
authors.initials: ME
authors.lastname: Adriaensen
authors.forename: C M
authors.initials: CM
authors.lastname: Schaefer-Prokop
authors.forename: T
authors.initials: T
authors.lastname: Stijnen
authors.forename: D A C
authors.initials: DA
authors.lastname: Duyndam
authors.forename: B A
authors.initials: BA
authors.lastname: Zonnenberg
authors.forename: M
authors.initials: M
authors.lastname: Prokop
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001254:Astrocytoma / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology; D002535:Cerebral Aqueduct / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D002648:Child; D015331:Cohort Studies; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014402:Tuberous Sclerosis / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology; D055815:Young Adult