Table 2.

Multivariate analysis models for heart dose and overall survival in esophageal cancer patients.

	Factors	Hazard ratio	95% Confidence interval		P value
Model 1 (heart V15)	Age >70 years	1.434	1.103	1.865	0.007
	Stage III/IV	1.670	1.297	2.152	<0.001
	Poor differentiation	1.469	1.168	1.848	0.001
	Surgery	0.483	0.383	0.608	<0.001
	Mean lung dose >10 Gy	1.374	1.085	1.741	0.008
	Heart V15 >87%	1.485	1.111	1.985	0.008
Model 2 (heart V20)	Age >70 years	1.410	1.084	1.833	0.010
	Stage III/IV	1.629	1.267	2.094	<0.001
	Poor differentiation	1.470	1.169	1.848	0.001
	Surgery	0.476	0.378	0.600	<0.001
	Mean lung dose >10 Gy	1.374	1.083	1.743	0.009
	Heart V20 >65%	1.313	1.027	1.680	0.030
Model 3 (heart V25)	Age >70 years	1.414	1.088	1.839	0.010
	Stage III/IV	1.614	1.256	2.075	<0.001
	Poor differentiation	1.475	1.173	1.855	0.001
	Surgery	0.489	0.388	0.616	<0.001
	Mean lung dose >10 Gy	1.370	1.080	1.737	0.009
	Heart V25 >61%	1.415	1.074	1.865	0.014
Model 4 (heart V30)	Age >70 years	1.390	1.069	1.809	0.014
	Stage III/IV	1.577	1.225	2.028	<0.001
	Poor differentiation	1.485	1.180	1.868	0.001
	Surgery	0.479	0.380	0.603	<0.001
	Mean lung dose >10 Gy	1.355	1.068	1.720	0.012
	Heart V30 >45%	1.402	1.077	1.826	0.012
Model 5 (heart V35)	Age >70 years	0.012	1.401	1.077	0.012
	Stage III/IV	0.000	1.585	1.231	<0.001
	Poor differentiation	0.001	1.476	1.173	0.001
	Surgery	0.000	0.480	0.381	<0.001
	Mean lung dose >10 Gy	0.008	1.380	1.088	0.008
	Heart V35 >37%	0.037	1.337	1.018	0.037
Model 6 (mean heart dose)	Age >70 years	1.423	1.095	1.848	0.008
	Stage III/IV	1.622	1.262	2.084	<0.001
	Poor differentiation	1.458	1.158	1.836	0.001
	Surgery	0.474	0.376	0.598	<0.001
	Mean lung dose >10 Gy	1.372	1.080	1.744	0.010
	Mean heart dose >27 Gy	1.275	1.002	1.622	0.048