Objective To use a meta-analysis method to establish quantitatively the association between the HER-2/neu gene amplification/enhanced protein expression status and the 5-year post-operative survival rate or median survival time in women with epithelial ovarian carcinoma. Methods We searched and screened Chinese and English literature published since 1989 to collect all retrospective cohort studies on the prognostic significance of HER-2/neu status in this population. The survival data were analyzed using Ludwig’s centered signed rank and the DerSimonian-Laird method. Results In total, 25 studies involving 3 251 patients were included. HER-2/neu was positive in 27.1% (95%CI 0 to 54.8%) of patients, which was not related to the pathological stage, type or grade of epithelial ovarian carcinoma. In HER-2/neu positive cases, the median survival time was shortened by 0.65 years, and the 5-year survival rate was lowered. The hazard ratio (HR) for mortality was 1.22 (95%C 1.09 to 1.36). By subgroup analysis, HER-2/neu protein expression was found to be most significant in prognostic assessment. Patients with a b positive value of HER-2/neu had an increased HR for the 5-year survival; and platinum-based chemotherapy was demonstrated to be less effective in HER-2/neu positive ovarian carcinoma. Conclusion In gynecological oncology, it is reasonable to measure HER-2/neu as a routine pathological marker to predict a patient’s prognosis and to determine the most appropriate adjuvant chemotherapy regimen.
Etiological and prognostic studies always directly reported effect size with its 95% confidence interval, hence, data transformation was needed when performing meta-analysis based on these studies. Using the data of risk ratio, hazard ratio, odds ratio and 95% confidence interval as an example, this paper introduces the process of using RevMan 5.3 software to convert data and perform meta-analysis.
Hazard ratio (HR) is usually regarded as the effect size in survival studies. Meanwhile, it is supposed to be perfect for pooling results in the meta-analysis of survival data. However, it does not function usually due to absence of original data for pooling HR. As a compromise method, entering data from reading Kaplan-Meier curves and follow-up times into the calculation spreadsheet can also be used to obtain related survival data. But related study on the subject is scarce, and opinions are inconsistent. Accordingly, we conduct this study to further illustrate the procedure in details.
Risk ratio (RR) and hazard ratio (HR) are two common effect measures in prospective studies. When describing the magnitude of clinical effects in the original study and meta-analysis, they cannot be used interchangeably. Selecting an appropriate measures and interpreting them correctly is critical in clinical research. In this study, we summarized similarities and differences between risk and hazard, compared differences between RR and HR in estimation methods and clinical interpretation. The magnitude of RR and HR estimated from the same studies were compared, and two feasible formulas converting between RR and HR were presented for meta-analysis.