Medknow Publications on behalf of Indian Cancer Society
Abstract
BACKGROUND: Clinical and histological criteria for ependymoma
prognosis are well recognized. Recently few studies have been done
based on Immunohistochemistry for prognostication of these tumours. In
this study we have correlated the histlogical spectrum with
immmunoexpression of p53 and Ki67 in these tumors. AIMS: To know the
incidence of ependymomas; study their morphological spectrum and to
evaluate expression of P53 and Ki 67 in diffferent morphological
subtypes. MATERIAL AND METHOD: A retrospective sudy was preformed on
70 ependymomas received in a period between 1994 and 2001. Entire
tissue received was processed for routine paraffin embedded H&E
stained sections. Immunocytochemistry was performed using antibodies to
GFAP, EMA, Pancytokeratin and synaptophysin, to differentiate papillary
ependymoma from choroid plexus papilloma; clear cell ependymoma from
oligodendroglioma and central neurocytoma; ependymoblastoma from other
embryonal tumours. p53 and Ki-67 immunohistochemistry was performed to
correlate their expression with various tumour grades and subtypes.
RESULTS: There were 3 cases (4.2%) of Grade I ependymoma (2 cases of
myxopapillary ependymoma and 1 case of subependymoma); 57 cases (81.5%)
of ependymoma grade II (43 of these were of classical variety, 11 of
clear cell ependymoma, 2 of papillary and 1 case of cellular
ependymoma). There were 9 cases (12.8%) of anaplastic ependymoma (one
of these was a clear cell ependymoma and 1 case (1.5%) of
ependymoblastoma CONCLUSION: p53 and Ki67 indices can be used in
routine diagnostic laboratories to supplement the tumor grade on
histology and more studies with follow up should be performed toanalyse
the prognsis of different subtypes. The expression of Ki 67 and p53 was
significantly higher in anaplastic ependymomas. 4 out of 11 cases of
clear cell ependymomas showed higher Ki 67 indices as compared to
classical grade II ependymomas, thus further highlighting the
importance of differentiating the various subtypes