Abstract

PURPOSE
The present study explores the expression rate of p53 mutation and the correlation between the expression of p53 protein and prognostic factors in medulloblastoma/ PNET (primitive neuroectodermal tumor).
MATERIALS AND METHODS
We studied retrospectively 24 patients with medulloblastoma/ PNET, who were admitted in Dong-A University Hospital, Pusan National University Hospital and Inje University Pusan Paik Hospital from 1988 to 1995. Detection of p53 mutations was made by immunohistochemical staining of p53 protein on paraffin- embedded tissues. The correlation between the expression of p53 protein and prognostic factors was evaluated by the Spearman correlation analysis.
RESULTS
p53 protein was expressed in 6 of 24 patients (25%). In 20 patients who could be evaluated for metastasis, 16 patients of M0, 1 patient of M1 and 3 patients of M2 were grouped by M stage, and the expression of p53 was detected in 1 of 16 M0 group (6.3%) and 3 of 3 M2 group (100%). p53 expression was significantly related to the M stage of medulloblastoma/PNET (r=0.73, p<0.001). The detection of p53 was not significantly associated with T stage, cellular differentiation and the relapse rate of medulloblastoma/ PNET.
CONCLUSION
The immunohistochemical detection rate of p53 protein in medulloblastoma/ PNET was 25%. The expression of p53 protein was significantly related to the M stage, with higher expression rate in M2 group of medulloblsatoma/PNET.

• Keywords: Medulloblastoma;Primitive neuroectodermal tumor;Immunohistochemical stain;p53