Table 6

Final multivariate model for younger patients with GBM, with HRs for EGFR based on p53 immunohistochemical status

Younger patients from the initial (n = 53) and validation sample (n = 42) were grouped and entered into a multivariate model, which included adjustments for age, KPS, protocol status, and extent of resection. In this model, significant variables included KPS (HR, 1.4; 95% CI, 1.2–1.7; P < 0.01) and protocol status (HR, 2.2; 95% CI, 1.4–3.6; P < 0.01). Age as a continuous variable was not significant (P = 0.36), nor was extent of resection (P = 0.69). When included in this model MIB-1 was not significant (P = 0.13) and was, therefore, excluded from the final model. Initial KPS and/or extent of resection were not available on 10 of the 95 patients; therefore, the total number of patients analyzed was 85.

Median survival (no. of cases)Cox analysis (EGFR+ vs. EGFR−)
p53−66 (28)44 (14)3.61.8–7.4<0.01
p53+56 (33)82 (10)0.70.3–1.40.28