Prognostic role of HER2 amplification based on fluorescence in situ hybridization (FISH) in pancreatic ductal adenocarcinoma (PDAC): a meta-analysis

BACKGROUND Previous studies have shown that human epidermal growth factor receptor 2 (HER2) may play an important role in the invasion and metastasis of pancreatic cancer, but the relationship between HER2 amplification level and prognosis of pancreatic cancer patients is still controversial. Therefore, we performed a meta-analysis to determine the prognostic significance of HER2 amplification based on fluorescence in situ hybridization (FISH) in patients with pancreatic cancer. METHODS PubMed, EMBASE, and Web of Science (Jan 2001 to Jun 2015) were searched. Only articles that detect the HER2 amplification by FISH method were included. RevMan 5.3 and STATA version 12 were used to perform this meta-analysis. Pooled calculations were carried out on hazard ratio (HR) and 95% confidence interval (CI) to assess the risk of disease. RESULTS A total of six eligible studies were enrolled in meta-analysis. The univariate analysis results showed that HER2 amplification was not significantly associated with patients' overall survival (pooled HR, 1.87, 95% CI, 0.64-5.46, P=0.25), which are maintained in one study of multivariate analysis (HR 0.51, 95% CI, 0.12-2.14, P=0.358). HER2 amplification also had no correlation with clinicopathological factors such as age, gender, lymph node metastasis, and tumor stage. CONCLUSIONS Our results showed that HER2 amplification based on FISH may not be a good prognostic factor for survival in patients with pancreatic cancer.