An independent survival prognostic role for human epidermal growth factor receptor 2 in gastric cancer: evidence from a meta-analysis.

BACKGROUND

Some studies have suggested that human epidermal growth factor receptor 2 (HER2) positive is associated with poor outcomes in gastric cancer (GC), whereas another inconsistent studies make the situation confused. This meta-analysis was performed to determine whether HER2 played an independent prognostic role in clinicopathological characteristics and survival outcomes of GC.

PATIENTS AND METHODS

Combination of GC and human epidermal growth factor 2 or HER2 or HER2/neu or erbB-2 or cerbB-2 or c-erbB2 or CD340 or p185 were used as key words. Data were compared according to the HER2 status. Time-to-event outcomes of overall survival (OS) were analyzed using Hazard Ratios (HRs) with fixed effect, while 5-year survival rate and clinicopathological factors were performed using odd ratios (OR) with random effect.

RESULTS

Nighteen trials, from 1986 to October 2013, were identified by two independent authors. A total of 6344 GC patients were included in this meta-analysis, with 1148 HER2 protein overexpression or gene amplification. Comparison of 5-year survival of patients with HER2-positive status versus HER2-negative status showed that OR was 0.58 [95% confidence interval (CI), 0.37-0.91], and the result was significant (P = 0.02). The survival outcome of HER2 protein overexpression or gene amplification patients was worse than those with normal HER2 (HR 1.15; 95% CI 1.12-1.18; P < 0.00001). However, the difference of III-IV stage ratio between HER2-positive and HER2-negative patients was not significant (OR 1.44; 95% CI 0.95-2.18; P = 0.09) even in the subgroup analysis of Asia (P = 0.12 and Europe (P = 0.51).

CONCLUSION

HER2 protein overexpression or gene amplification in GC patients is associated with a poor survival outcome, and may play a role in GC tumorigenesis.