Objective: To study the expression of epidermal growth factor receptor (EGFR) and Ki-67 antigen in human brain ependymoma and the correlation between them.
Methods: Immunohistochemistry was used to detect the expression of EGFR and Ki-67 antigen in 40 specimens of brain ependymoma, 8 specimens of normal brain tissues, and 8 specimens of glioblastoma, all obtained during operation.
Results: The EGFR positive rate of the III - IV grade ependymoma tissues was 75%, significantly higher than that of the grade I - II grade ependymoma tissues (25%, P < 0.05). The specimens of glioblastoma were all EGFR positive. The EGFR positive rate of the recurrent ependymoma tissues (5/6) was significantly higher than that of the primary ependymoma tissues (9/34, P < 0.05). The positive rate of Ki-67 L1 in the III - IV grade ependymoma tissues was (9.5 +/- 5.6)%, significantly higher than that in the grade I - II grade ependymoma tissues [(2.2 +/- 1.4)%, P < 0.05)]. The positive rate of Ki-67 L1 in the glioblastoma tissues was (9.8 +/- 6.3)%. The positivity of EGFR was positively correlated with the grade level of ependymoma and Ki-67 L1 positivity (both P < 0.01).
Conclusion: EGFR expression positive rate increases with tumor grading. The positive rate of recurrent ependymoma is higher than that of the primary ependymoma. The expression of Ki-67 antigen is positively correlated with the expression of EGFR in difference grades.