POTENTIAL PROGNOSTIC VALUE OF C-ERBB-2 EXPRESSION IN MEDULLOBLASTOMASIN VERY YOUNG-CHILDREN

Purpose: The expression of the c-erbB-2 oncogene was studied in childh ood medulloblastoma to evaluate its prognostic value, which has been c laimed previously. Patients and Methods: Tumor material from 45 patien ts <15 years old at diagnosis was studied using 3 monoclonal antibodie s against the internal and external domains of the c-erbB-2 oncogene p roduct. Results: Six of the 45 (13%) tumor specimens were found to be positive. C-erbB-2 expression was found more often in patients <3 year s old at diagnosis (4 of 15 patients, 27%) than in older patients (2 o f 30, 6.6%). During the follow-up period (5.8+/-2.8 years) all patient s with c-erbB-2 expression died of disease (after 1.2+/-0.7 years). Ka plan-Meier estimation revealed a highly significant correlation of c-e rbB-2 expression and survival (p = 0.002). A further study of the expr ession of synaptophysin and the glial fibrillary acidic protein (GFAP) in the 45 tumors revealed a negative correlation of the expression of c-erbB-2 and these proteins. Conclusion: C-erbB-2, which may be predo minantly expressed by less differentiated tumors, was found to delinea te a poorer prognostic subgroup, especially when diagnosed in patients <3 years old.