Table 2. Cox proportional hazards regression model of prognostic variables for overall survival.

Prognostic variable	P-value	Risk ratio(95% CI)
Paf15	0.028*	0.479(0.248-0.923)
Gender	0.734	1.133(0.551-2.331)
Age	0.237	0.677(0.355-1.292)
Histological grade	0.197	0.501(0.175-1.433)
Tumor size	0.461	0.781(0.375-1.629)
pTNM Stage	0.327	0.695(0.336-1.438)
Infiltration degree	0.092	3.409(0.819-14.196)
Lymph node metastasis	0.586	0.563(0.071-4.457)

^*Correlation significant at the 0.05 level (two tailed). CI: confidence interval.