Primitive neuroectodermal tumor of the posterior fossa: medulloblastoma: evaluation of the proliferative index by means of monoclonal antibody Mib-1, its prognostic correlation and therapeutics implications

THESES

Primitive neuroectodermal tumor of the posterior fossa: medulloblastoma. Evaluation of the proliferative index by means of monoclonal antibody mib-1, its prognostic correlation and therapeutics implications (Abstract)^*. Thesis. São Paulo, 2002.

Antonio Fernandes Ferrari

^{Address to correspondence}

Tumors result from the unbalance between cellular proliferation and its death. As cellular proliferation increases, the more aggressive the tumor gets. The gold-standard method for labelling which cells are proliferating is the immunohistochemistry using monoclonal antibodies that recognize these cells. In the past few years, the monoclonal antibody Mib-1 has been used by researchers in order to retrospectively study paraffin imbed tumor fragments. The medulloblastoma is the most frequent maling central nervous system tumor in childhood. It seems to be originated from the inferior medullary velum and it occupies the fourth ventriculum invading cerebellar hemispheres and brain stem.

This retrospective study presents an analysis of the cellular proliferation index of the posterior fossa medulloblastomas collected from 22 patients at A. C. Camargo Hospital, from January 1999 to December 1999. The histopathological diagnosis was confirmed by H.E. and LI was acquired by Mib-1 which detects proliferating cells during G1, G2, S and M phases. The objectives were: determination of the mean Mib-1 LI value from these patients, correlating sex, age, race, clinical and radiological findings and treatment as well as the prognostic value of the method.

The results demonstated that the mean Mib-1 value has no significant statistic correlation with sex, age, race, clinical and radiological findings and p53, although patients harboring tumor with proliferation indexes lower than the mean value had a better prognosis.

In conclusion, these methods have to be placed as routine for patients harboring medulloblastomas, and the ones who have LI greater than the mean value found in this study have to be treated aggressively.

Keywords: primitive neuroectodermal tumor, posterior cranial fossa, medulloblastoma, proliferative index.

Address to correspondence

Antonio Fernandes Ferrari

Rua Mario Moretti 76

19060-570 Presidente Prudente SP

*

Tumor neuroectodérmico primitivo da fossa posterior: meduloblastoma. Avaliação do padrão proliferativo celular, sua correlação prognóstica e implicações terapêuticas (Resumo). Tese de Doutorado, Faculdade de Medicina da Universidade de São Paulo (Área: Neurologia). Orientador: José Píndaro Pereira Plese.

Publication Dates

• Publication in this collection
  16 Apr 2003
• Date of issue
  Mar 2003