Long-term survival and risk factors in esophageal squamous cell carcinoma: A Kaplan-Meier and cox regression study

Table 1 Clinical characteristics of the 115 esophageal squamous cell carcinoma patients

Variables	Group	Death (n = 77)	Survival (n = 38)	χ2/t	P value
Gender, n (%)				1.019	0.313
	Male	63 (81.8)	28 (73.7)
	Females	14 (18.2)	10 (26.3)
Age (year), n (%)				0.059	0.808
	≤ 60	24 (31.2)	11 (28.9)
	> 60	53 (68.8)	27 (71.7)
BMI (kg/m2)		22.09 ± 2.94	20.81 ± 2.68	2.251	0.026
Tumor location, n (%)				5.493	0.064
	Upper segments	14 (18.2)	3 (7.9)
	Middle segments	53 (68.8)	24 (63.2)
	Lower segments	10 (13.0)	11 (28.9)
Degree of differentiation, n (%)				4.540	0.103
	Poorly differentiated	21 (27.3)	6 (15.8)
	Moderately differentiated	54 (70.1)	28 (73.7)
	Well-differentiated	2 (2.6)	4 (10.5)
Perineural invasion, n (%)				1.255	0.263
	No	72 (93.5)	38 (100.0)
	Yes	5 (6.5)	0 (0.0)
Tumor length (mm)		40.18 ± 15.09	39.21 ± 11.49	0.350	0.727
Tumor width (mm)		25.66 ± 11.26	24.82 ± 8.37	0.411	0.682
Retrieved lymph nodes number		14.23 ± 10.05	14.76 ± 7.97	0.284	0.777
Smoking, n (%)				5.216	0.022
	No	60 (77.9)	36 (94.7)
	Yes	17 (22.1)	2 (5.3)
Drinking, n (%)				1.612	0.105
	No	68 (88.3)	37 (97.4)
	Yes	9 (11.7)	1 (2.6)

Table 2 Univariate and multivariate Cox regression equations affecting prognosis of patients with esophageal squamous cell carcinoma

Factors	Univariate Cox		Multivariate Cox
	HR (95%CI)	P value	HR (95%CI)	P value
Gender	1.197 (0.896-1.599)	0.225	-	-
Age	0.862 (0.532-1.398)	0.548	-	-
BMI	1.111 (1.032-1.197)	0.005	1.137 (1.054-1.226)	0.001
Tumor location
Upper segments	1	-	1	-
Middle segments	0.521 (0.287-0.944)	0.032	0.441 (0.240-0.810)	0.008
Lower segments	0.399 (0.177-0.901)	0.027	0.328 (0.144-0.750)	0.008
Degree of differentiation
Well-differentiated	1	-	-	-
Poorly differentiated	3.045 (0.712-13.015)	0.133	-	-
Moderately differentiated	2.265 (0.552-9.302)	0.257	-	-
Perineural invasion	7.947 (3.079-20.513)	< 0.001	13.381 (4.899-36.547)	< 0.001
Tumor length	1.011 (0.994-1.029)	0.196	-	-
Tumor width	1.014 (0.991-1.037)	0.240	-	-
Retrieved lymph nodes number	1.008 (0.983-1.033)	0.551	-	-
Smoking	1.947 (1.135-3.339)	0.016	2.415 (1.388-4.203)	0.002
Drinking	1.510 (0.753-3.030)	0.246	-	-

HR: Hazard ratio; 95%CI: 95% confidence interval; BMI: Body mass index.