The second method was defining nuclear and cytoplasmic staining as positive separately in IHC examination, which was used only in 3 studies. We made an effort to contact all primary authors of studies by e-mail to standardize their data according to the meta-analysis definitions whenever possible. In the present study, only nuclear staining was regarded as positive
[18–20]. All data were extracted independently by 2 reviewers (Wang XT and Kong FB) according to the prespecified selection criteria. The following data were extracted: the year of publication, first author’s surname, number of cases and controls, and numbers of different clinical and pathologic parameters. Statistical analysis selleckchem Results were expressed with risk ratio (RR) for dichotomous data, and 95% confidence intervals (CI) were counted [21]. P<0.05 was required for the overall RR to be statistically GSK872 chemical structure significant. The between-study heterogeneity was assessed using I2 and χ2 measures. The pooled statistical analysis was calculated using the fixed effects model, but a random-effect
model was performed when the P value of heterogeneity test was <0.1. The data on the predictive ability of Cdx2 overexpression for 5-year survival rate were combined across studies using fixed and random effect models for the synthesis of hazard ratio (HR). The HR of 5-year survival rate was calculated from the reported data directly by number of events within 5 years after surgery was used, or data reading from Kaplan-Meier survival curve. The funnel plot was examined to explore the possibility of publication bias [21–23]. Kaplan-Meier curves were read by Engauge Digitizer version 2.11 (free software downloaded from http://sourceforge.net). Neratinib ic50 The data analysis
was performed using the meta-analysis software Review Manager (RevMan) v5.0.17 (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2008; http://cc-ims.net/revman/download). Results Eligible studies As shown in Figure 1, our initial search yielded 412 studies. According to the inclusion and exclusion criteria, 13 papers [9, 11, 13–16, 24–30] were recruited into our meta-analysis. Only four studies reported the association between the Cdx2 and 5-year survival rate [9, 15, 16, 26]. Studies were carried out in Japan, China, Korea, Turkey and Germany. Table 1 presents the study check details characteristics for the included trials. Figure 1 Flow chart for our meta-analysis. Table 1 Study characteristics for the included studies Autor (year-country) Total number of patients Median age (range) Male: Female Adequacy of antibody methods Blinding of Cdx2 evaluation Cdx2 positive Cdx2 negative Cdx2 positive Cdx2 negative Ge [34] 59 107 52.2 37:22 51:56 Yes Yes (2008-china) (32–72) Okayama [14] 55 80 63.4 46:9 45:35 Yes Yes (2009-Japan) (31–87) Kim [5] 150 109 57.8 114:36 61:48 Yes Yes (2006- Korea) Roessler [15] 109 81 61.