Lack of Effects of HER-2/neu on Prognosis in Colorectal Cancer: a Meta-analysis

Abstract

Background: The prognostic value of human epidermal growth factor receptor-2 (HER-2/neu) for survivalof patients with colorectal cancer (CRC) is still ambiguous. We therefore performed a meta-analysis to evaluateits prognostic significance. Materials and
Methods: We searched the MEDLINE and EMBASE databases forpublished literature investigating associations between HER-2/neu status and overall survival of patients withCRC. A meta-analysis was performed using a DerSimonian-Laird model and publication bias was investigatedby Begg’s and Egger’s tests. Subgroup analysis was also conducted according to the study design type, studyquality score, cut-off value for HER-2/neu overexpression, publication region, patient number and publicationyear.
Results: A total of 17 eligible studies involving 2,347 patients were identified for this meta-analysis. Thecombined hazard ratio (HR) was 1.31 (95% confidence interval (CI): 0.96-1.79), suggesting that HER-2/neuoverexpression was not significantly associated with overall survival of patients with CRC. However, subgroupanalysis revealed that HER-2/neu overexpression had an unfavorable impact on survival when the analysiswas restricted to subgroups of study quality score ≤ 5 (HR=1.56, 95%CI: 1.17-2.10), Asian patients (HR=1.74,95%CI: 1.22-2.49), patient number ≤ 106 (HR=1.57, 95%CI: 1.01-2.44), publication year before 2003 (HR=1.59,95%CI: 1.02-2.49), and prospectively designed study (HR=3.62, 95%CI: 1.42-9.24). The effect disappeared insubgroups of study quality scores > 5 (HR=0.69, 95%CI: 0.33-1.44), non Asian patients (HR=1.14, 95%CI:0.77-1.70), patients’ number > 106 (HR=1.07, 95%CI: 0.67-1.72), publication year after 2003 (HR=1.13, 95%CI:0.76-1.69), and retrospectively designed study (HR=1.22, 95%CI: 0.89-1.67).
Conclusions: Our meta-analysissuggests that HER-2/neu overexpression might not be a significantly prognostic indicator for patients with CRC.Further studies are required to confirm these results.

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