Fig. 2

The X-tile analysis of best-cutoff points of age and tumor size variables. a X-tile plot of training sets in age; b the cutoff point was highlighted using a histogram of the entire cohort; c the distinct prognosis determined by the cutoff point was shown using a Kaplan-Meier plot (low subset = blue, middle subset = gray, high subset = magenta); d X-tile plot of training sets in tumor size; e the cutoff point was highlighted using a histogram; f Kaplan-Meier plot of prognosis determined by the cutoff point (low subset = blue, middle subset = gray, high subset = magenta)