Prognosis of radiotherapy for esophageal cancer in elderly patients exceeding seventy-five years old

Table 2 Univariate and multivariate Cox analysis of the determinants of overall survival of patients

Variables	Univariate analysis				Multivariate analysis
	HR	Lower 95%CI	Upper 95%CI	P value	HR	Lower 95%CI	Upper 95%CI	P value
Age
≥ 75 and < 80	1
≥ 80	1.147	0.769	1.710	0.502
Sex
Female	1
Male	0.656	0.427	1.009	0.055
Marital status
Married	1
Unmarried	0.538	0.132	2.188	0.387
Smoke
No	1
Yes	0.821	0.544	1.239	0.348
Drink
No	1
Yes	0.869	0.545	1.387	0.557
C stage
I-II	1				1
III-IVa	2.261	1.189	4.298	0.013	2.421	1.242	4.718	0.009
IVb	3.444	1.593	7.446	0.002	4.222	1.888	9.438	< 0.001
T stage
T1-T2	1
T3-T4	1.575	0.876	2.831	0.129
N stage
Negative	1
Positive	2.030	1.104	3.732	0.023
M stage
M0	1
M1	1.761	1.038	2.986	0.036
Tumor length
< 6	1
≥ 6	1.261	0.836	1.904	0.269
Tumor location
Upper thoracic	1
Middle thoracic	1.054	0.632	1.759	0.840
Lower thoracic	1.146	0.665	1.976	0.623
ECOG
0-1	1
2	2.023	0.820	4.995	0.126
CCI
0	1				1
≥ 1	1.620	1.080	2.429	0.020	1.539	1.015	2.332	0.042
NRS2002
< 3	1				1
≥ 3	2.215	1.466	3.348	< 0.001	2.491	1.601	3.875	< 0.001
BMI
< 18.5	1
≥ 18.5	0.756	0.482	1.183	0.221
Weight loss
< 10%	1				1
≥ 10%	2.947	1.473	5.898	0.002	1.798	0.870	3.715	0.113
Radiation dose
< 60	1
≥ 60	0.771	0.511	1.164	0.217
Chemotherapy
No	1
Yes	0.847	0.543	1.320	0.463

HR: Hazard ratio; CI: Confidence interval; BMI: Body mass index; ECOG: Eastern Cooperative Oncology Group; CCI: Charlson comorbidity index; NRS2002: Nutritional risk screening 2002.