Abstract

BACKGROUND
Medulloblastoma is a highly malignant neuroepithelial tumor of the childhood, less frequently, of adults, located in the posterior cranial fossa. It shows multiple lines of differentiation, expressing neuronal, glial, mesenchymal and ectodermal markers. The prognostic significance of cell differentiation has been studied, but received little agreement. In highly malignant tumors, very high proliferative index has been demonstrated. A major contributor to cell loss in medulloblastoma is reported to be apoptosis. In medulloblstoma, a linear relation between apoptotic index and proliferative index has not been convincingly demonstrated.
METHODS
We analyzed the immunohistochemical features, proliferative indices and apoptotic indices in medulloblastoma patients with regard to their clinical courses. Clinical features of 58 patients with medulloblastoma were reviewed. The presence of glial fibrillary acidic protein, synaptophysin, vimentin, and epithelial membrane antigen were examined with immunohistochemical method. The proliferative index (Ki-67) and caspase 3 expressing rate were calculated.
RESULTS
There was no significant correlation between the prognosis and the degree of cell differentiation. The positive correlation was noted between proliferative index and apoptotic index in a tumor mass.
CONCLUSIONS
Only proliferative index could be used as a prognostic factor.

• Keywords: Medulloblastoma;Immunohistochemistry;Ki-67 antigen;Apoptosis;Caspases