Statistical Analysis
Statistical analyses were calculated with the Biometrical Analysis of Sampling (BIAS 11.06 Software, Frankfurt, Germany). Categorical data were presented as percentages. Continuous data were illustrated as mean value ± standard deviation. Continuous and discrete variables are expressed as mean ± SD or median and range for data not normally distributed. Comparison of the two groups were analysed using the chi-square test, Fisher´s exact test for qualitative data and Mann-Whitney U test for quantitative data, respectively. Survival was calculated applying the Kaplan-Meier estimates and additionally compared with log rank test between the two groups. A p-value of less than 0.05 was defined statistically significant.