Association of p53/p21 expression with cigarette smoking and prognosis in esophageal squamous cell carcinoma patients

Table 4 Log-rank and proportional hazard regression analysis (Cox method) for clinicopathological parameters in esophageal squamous cell carcinoma patients

	Mean survival time (mo)	Log rank P value	Cox-regression
			HR	95% CI	P value1
Operability
Operable	12.68 ± 2.56	0.001	2.27	1.30-3.97	0.004
Inoperable	7.08 ± 1.72
p21 over-expression
Yes	7.41 ± 1.78	0.009	1.82	1.02-3.25	0.04
No	11.71 ± 2.36
p53 over-expression
Yes	8.00 ± 2.06	0.30	1.23	0.67-2.26	NS
No	10.69 ± 2.08
Tumor size (cm)
< 3	12.58 ± 3.28	0.06	1.75	0.92-3.32	0.08
≥ 3	9.43 ± 2.18
Age (yr)
< 60	12.61 ± 2.46	0.006	2.30	1.29-4.09	0.005
≥ 60	8.40 ± 2.14

¹Not statistically significant by χ² test. NS: Not significant; HR: Hazard ratio; CI: Confidence interval.