Assessment of expression of epidermal growth factor receptor and p53 in meningiomas.

BACKGROUND: Meningiomas represent about 30% of primary adult central nervous system tumors. Though slow growing, they recur, causing significant morbidity and mortality.

OBJECTIVE: The objective of the following study is to grade meningiomas according to World Health Organization (WHO) 2007 criteria and to correlate the grade with degree of expression of epidermal growth factor receptor (EGFR) and p53.

MATERIALS AND METHODS: Meningiomas diagnosed in the year 2010 in the Department of Pathology of our institute, were included in the study. Clinical and radiological findings were noted from medical records. The histopathology slides were reviewed and the tumors were graded according to WHO 2007 criteria. Tissue microarrays (TMA) were prepared and immunohistochemical analysis with epithelial membrane antigen, Vimentin, Ki67, EGFR and p53 was performed on the TMA slides.

RESULTS: A total of 79 meningiomas diagnosed during the study period included 30 male and 49 female patients with an age range of 10-75 years. There was a female preponderance with M:F ratio of 1:1.63. EGFR was found to be higher in grade I (82.93%) compared with grade II (35.71%) and grade III tumors (20%) with an overall positivity of 60.81%. Mean p53 indices were higher in grade III (50%) compared with grade II (39.29%) and grade I tumors (38.46%) with an overall positivity of 39.44%. Ki67 labeling index (LI) was significantly high in grade III (16.4%) compared with grade II (6.46%) and grade I tumors (3.13%).

CONCLUSION: EGFR expression and Ki67 LI correlated with grade of meningioma P < 0.0001 and P < 0.0001 respectively which were statistically significant whereas p53 expression did not correlate (P - 0.90).