Univariate and multivariable analyses of CSS and overall survival ( OS ) of patients showed that age > 65 years is a strong independent poor prognostic factor ( 5-y OS 92.1 % and 78.4 % in 65 years and > 65 years patients , respectively , P < .0001 ; 5-y CSS 93.8 % and 83.5 % in 65 years and > 65 years patients , respectively , P = .003 ) .