Table 4.

Univariate Kaplan-Meier analysis of survival

Variable	Five-year overall survival	P value	Five-year disease-free survival	P value
Age		0.613		0.329
<70 years	61		51
≥70 years	59		46
Gender		0.127		0.208
Male	64		54
Female	57		49
Charlson comorbidity index		0.078		0.120
≤ 2	67		56
> 2	51		47
ASA score		0.091		0.074
I-II	65		55
III	52		42
Tumor differentiation		0.017		0.038
Differentiated	71		61
Undifferentiated	48		46
T stage		0.010		0.018
T1-T2	72		64
T3-T4	43		40
N stage		0.023		0.020
N0-N1	69		65
N2-N3	46		44
Postoperative complications		0.247		0.187
No	63		58
Yes	56		51