title: Chemotherapy increases long-term survival in patients with adult medulloblastoma--a literature-based meta-analysis.
abstract: BACKGROUND
  Adult medulloblastoma is a potentially curable malignant entity with an incidence of 0.5-1 per million. Valid data on prognosis, treatment, and demographics are lacking, as most current knowledge stems from retrospective studies. Surgical resection followed by radiotherapy are accepted parts of treatment regimes; however, established prognostic factors and data clarifying the role of chemotherapy are missing.
  
  
  METHODS
  We investigated 227 publications from 1969-2013, with 907 identifiable, individual patients being available for meta-analysis. Demographic data, risk stratification, and treatment of these patients were similar to previous cohorts.
  
  
  RESULTS
  The median overall survival (mOS) was 65 months (95% CI: 54.6-75.3) , the 5-year overall survival was 50.9% with 16% of the patients dying more than 5 years after diagnosis. Incomplete resection, clinical and radiological signs for brainstem infiltration, and abstinence from radiotherapy were predictive of worse outcome. Metastatic disease at tumor recurrence was identified as a new prognostic factor, while neither metastasis at initial diagnosis nor desmoplastic/classic histology was correlated with survival. Patients receiving chemotherapy first-line survived significantly longer (mOS: 108 mo, 95% CI: 68.6-148.4) than patients treated with radiation alone (mOS: 57 mo, 95% CI: 39.6-74.4) or patients who received chemotherapy at tumor recurrence. This effect was not biased by tumor stage or decade of treatment. Importantly, (neo)adjuvant chemotherapy also significantly increased the chance for long-term survival (>5 y) compared with radiotherapy alone or chemotherapy at tumor recurrence.
  
  
  CONCLUSIONS
  This meta-analysis clarifies relevant prognostic factors and suggests that chemotherapy as part of first-line therapy improves overall survival and increases the proportion of patients with long-term survival.
authors.affiliation: Department of Neurology, RWTH Aachen, Aachen, Germany (S.K., C.P.B., D.B.); Department of Neurology, University Hospital Odense and Clinical Institute, University of Southern Denmark, Odense, Denmark (C.P.B., D.B.).
authors.forename: Selin
authors.initials: S
authors.lastname: Kocakaya
authors.affiliation: Department of Neurology, RWTH Aachen, Aachen, Germany (S.K., C.P.B., D.B.); Department of Neurology, University Hospital Odense and Clinical Institute, University of Southern Denmark, Odense, Denmark (C.P.B., D.B.).
authors.forename: Christoph Patrick
authors.initials: CP
authors.lastname: Beier
authors.affiliation: Department of Neurology, RWTH Aachen, Aachen, Germany (S.K., C.P.B., D.B.); Department of Neurology, University Hospital Odense and Clinical Institute, University of Southern Denmark, Odense, Denmark (C.P.B., D.B.).
authors.forename: Dagmar
authors.initials: D
authors.lastname: Beier
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D003131:Combined Modality Therapy / Q000379:methods; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008527:Medulloblastoma / Q000175:diagnosis / Q000188:drug therapy* / Q000473:pathology / Q000628:therapy; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: adult medulloblastoma; chemotherapy; long-term survival; meta-analysis; radiotherapy