Table 1. Tumor characteristics of ESCC patients.

Variable	Chinese resident (N=1,718)			Caucasians (N=1,624)		P
	Freq	%		Freq	%
Gender						<0.01
Male	1,397	81.32		1,003	61.76
Female	321	18.68		621	38.24
Age group						<0.01
<60	592	34.46		353	21.74
60~69	470	27.36		450	27.71
70+	656	38.18		821	50.55
AJCC tumor stage						<0.01
1, 2	868	50.52		728	44.83
3, 4	850	49.48		896	55.17
Primary site						<0.01
Cervical esophagus	3	0.17		101	6.22
Upper esophagus	63	3.67		206	12.69
Middle esophagus	585	34.05		595	36.64
Lower esophagus	282	16.41		497	30.60
Overlapping lesion of esophagus	158	9.20		91	5.60
Esophagus, NOS	627	36.55		134	8.25

ESCC, esophageal squamous cell carcinoma; AJCC, American Joint Commission on Cancer.