Fig. 2

Overall survival curves according to age - naïve T group. Patients were divided into six groups according to age and value of naïve T cell count. Kaplan-Meier analysis revealed that survival rate was significantly different between six age-naïve T groups (p < 0.001). In pairwise comparison, survival rate was significantly lower in the oldest group when compared with other groups. Patients age 61–75 years old with a lower naïve T cell count had a significant lower survival rate than those in the same age period but with a higher naïve T cell count (p < 0.001). Patients aged 46–60 years old with a lower naïve T cell count also had a significant lower survival rate than those in the youngest age period (p = 0.04). Patients aged 46–75 years old with a higher naïve T cell count seemed to have a similar survival rate compared to patients younger than 46 years old