title: Prognostic factors in adult medulloblastoma. A clinico-pathologic study.
abstract: OBJECTIVE
  Medulloblastoma in adults is a rare tumor. The small number of cases in the reported series has not permitted a definite assessment of the prognostic role of clinical, pathologic and cell kinetics factors. The largest series of medulloblastoma in adults treated in a single institution is herein reported.
  
  
  METHODS
  The clinical, therapeutic, pathologic and proliferation features of medulloblastoma in 44 adult patients (> 18 years) were analyzed retrospectively with regard to postoperative survival. The proliferation potential of each tumor was evaluated by the immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA) and Ki-67, clone MIB-1, in paraffin sections.
  
  
  RESULTS
  The overall 5- and 10-year survival rates were 40% and 35.6%, respectively. Significant factors in predicting a longer postoperative survival were: age < 37 years, decade of management (1977-1990), radiotherapy (50-55 Gy on the posterior fossa and 30-35 Gy on the spinal cord) and nuclear isomorphism. When corrected for adequacy of radiotreatment, desmoplastic type and differentiation were significantly correlated with a shorter survival. The PCNA-labelling index (LI) ranged from 34.5 to 82.2%, the MIB-1-LI ranged from 9.6 to 64.7%. No association was found between PCNA- or MIB-1-LI values and microscopic features, or between LI values and prognosis.
  
  
  CONCLUSIONS
  Contrary to a general assumption, desmoplastic medulloblastoma and differentiated medulloblastoma are negative prognostic factors in adequately radiotreated adult patients. This may possibly be referred to lower radiosensitivity of these tumor variants. The LI with PCNA or Ki-67 is of no help in identifying aggressive tumors.
authors.affiliation: Clinica Neurologica II, Università di Torino, Italy.
authors.forename: M T
authors.initials: MT
authors.lastname: Giordana
authors.forename: P
authors.initials: P
authors.lastname: Cavalla
authors.forename: A
authors.initials: A
authors.lastname: Chiò
authors.forename: S
authors.initials: S
authors.lastname: Marino
authors.forename: R
authors.initials: R
authors.lastname: Soffietti
authors.forename: M C
authors.initials: MC
authors.lastname: Vigliani
authors.forename: D
authors.initials: D
authors.lastname: Schiffer
mesh_terms: D000328:Adult; D017677:Age Distribution; D002528:Cerebellar Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000532:radiotherapy; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen; D008297:Male; D008527:Medulloblastoma / Q000737:chemistry / Q000473:pathology* / Q000532:radiotherapy; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis; D009687:Nuclear Proteins / Q000032:analysis; D011379:Prognosis; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis
chemical_list: D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen