Survival impact of epidermal growth factor receptor overexpression in patients with non-small cell lung cancer: a meta-analysis

Abstract

Background: It is thought that overexpression of epidermal growth factor receptor (EGFR) in non-small cell lung cancer (NSCLC) might compromise patient survival, presumably by promoting tumour growth by an autocrine mechanism. However, conflicting results have been reported from various laboratories, and the clinical importance of EGFR overexpression remains unsettled. Methods: A meta-analysis of previous studies was performed to quantitatively review the effects of EGFR overexpression on survival in patients with NSCLC using a DerSimonian-Laird random effects model. Eighteen studies including 2972 patients were subjected to final analysis. Results: Overall, positivity for EGFR overexpression differed between histological types: 39% in adenocarcinomas, 58% in squamous cell carcinomas, 38% in large cell carcinomas, and 32% in cancers in a miscellaneous category (p,0.0001). The combined hazard ratio (HR) was 1.14 (95% CI 0.97 to 1.34; p = 0.103), indicating that EGFR overexpression has no significant impact on survival. When only the 15 immunohistochemistry based studies were considered, the combined HR was 1.08 (95% CI 0.92 to 1.28; p = 0.356), again suggesting that EGFR overexpression has no impact on survival. Heterogeneity testing indicated that there was heterogeneity between studies but publication bias was absent, which suggests that the summary statistics obtained may approximate the actual average. Conclusions: EGFR overexpression was not associated with poorer survival in patients with NSCLC. Specific mutations of the EGFR gene will need further study in terms of survival implications.

Abnormalities of epidermal growth factor receptor in lung squamous‐cell carcinomas, adenosquamous carcinomas, and large‐cell carcinomas

“…EGFR protein overexpression was found in 35 of 42 nonadenocarcinoma NSCLCs (83%). Patients in our cohort thus showed a higher frequency of EGFR protein overexpression than those in a previous meta-analysis, 28 which may be because of differences in ethnicity. Whereas we have previously reported that EGFR overexpression is strongly correlated with TKD mutations in adenocarcinomas, 23 no such correlation was demonstrated in the present study for nonadenocarcinoma NSCLCs.…”

“…28 For EGFR Western blotting analysis, 100 lg of tumor or normal lung protein was used. Protein samples were subjected to Western blotting analyses using anti-EGFR polyclonal antibody (Santa Cruz Biologicals, Santa Cruz, CA) according to the manufacturer's instructions.…”

Role of Epidermal Growth Factor Receptor Expression on Patient Survival in Pancreatic Cancer: A Meta-Analysis

“…Some data have showed that EGFR expression in pancreatic cancer does not reflect the prognosis of patients [10,11]. Accurate and conclusive evaluation of the clinical significance of EGFR expression is important to pancreatic cancer for choosing appropriate future molecular targets [17]. Therefore, we have carried out a meta-analysis of the literature to quantitatively assess the prognostic significance of EGFR expression on survival in patients with pancreatic cancer.…”

Non-small cell lung cancer - genetic predictors

“…Increased EGFR expression was considered to be a poor prognostic factor in NSCLC patients 12,13 but a meta-analysis combining 18 studies of 2972 patients did not confirm the prognostic significance of EGFR expression (HR=1.14; 95% CI 0.97-1.34; P=0.103) (ref. 14 ). The predictive value of EGFR amplification/overexpression for responsiveness to EGFR tyrosine kinase inhibitors (EGFR TKIs) was tested in several studies.…”