30 (95% CI: 0.13-0.55). All three groups, ADC, SCC and the combination

had a Gemcitabine mw statistically significant heterogeneity (P<0.001), I2=91.67%, I2=88.08 and I2=95.03 respectively. We also evaluated the regional influence of HER2+ in EC. It was found that Asia had an ER of 0.42 (95% CI: 0.22-0.64) with a statistically significant heterogeneity (I2=88.82%, P=0.003). Europe had an ER of 0.17 (95% CI: 0.10-0.27) with a statistically significant heterogeneity Inhibitors,research,lifescience,medical (I2=90.79%, P=0.001). North America had an ER of 0.33 (95% CI: 0.21-0.48). There was statistically significant heterogeneity (I2=86.93%, P<0.001). Figure 4 HER2+ event rates in EC studies using IHC EC & ISH We found an ER of 0.15 (95% CI: 0.10-0.22) (Figure 5). There Inhibitors,research,lifescience,medical was statistically significant heterogeneity (I2=86.01%, P<0.001). The Egger test for publication bias was not significant (P=0.43). The studies were also evaluated by cancer types (ADC & SCC) (Figure 6). We found an ER of 0.15 (95% CI: 0.09-0.26) for ADC, with a statistically significant heterogeneity (I2=91.13%, P<0.001). The ER for SCC was 0.16 (95% CI: 0.10-0.24), with a statistically non-significant heterogeneity (I2=0%, P=0.43). We also evaluated the regional influence of HER2+ in EC. It was found that Europe had an ER of 0.12 (95% CI: 0.08-0.19).

There was statistically non-significant heterogeneity (I2=60.17%, P=0.08). North America had an ER of 0.20 (95% CI: 0.08-0.41). There Inhibitors,research,lifescience,medical was statistically significant heterogeneity (I2= 93.83%, P<0.001).

Figure 5 HER2+ event rates in EC studies using FISH Figure 6 HER2+ event rates in EC studies by cancer types (ADC or SCC) EC & survival Inhibitors,research,lifescience,medical The pooled HR is 1.45 (95% CI: 0.85-2.48). It was not statistically significantly (P=0.17). Between groups HER2+ & HER2-, a difference of 7 months was noted (95% CI: 6-20 months). This was not statistically significant (P=0.29). Discussion Our meta-analysis shows that there is a high prevalence Inhibitors,research,lifescience,medical rate of HER2+ in both BE and EC populations, 24% and 26%, respectively. The prevalence rate of HER2+ in EC and BE is higher than that of Breast Cancer (12,48). The ratio between male and females in the studies was 5:1 in both BE and EC subjects. From EC studies it was shown that although the proportion of women diagnosed with EC was lower than Oxygenase males, the prevalence of HER2+ was slightly higher. Men had an event rate of 25.14%, while women were 28.14%. On the contrary, analysis of the two studies that had reported HER2+ percentage among males and females in BE studies showed that the prevalence of HER2+ among male was almost double that of women. Both BE and EC studies have shown that Stage III had the highest percentage of patients. The low level of HER2+ in Stage I and II can be explained by the late diagnosis of the disease. The significance of tumour staging in HER2+ is still not clear. Ryu et al. (49) has shown that an increase in HER2 in the serum was correlated to tumour staging and histological grading in breast cancer patients.