Table 1.

Characteristics of patients with esophageal squamous cell carcinoma n (%)

	Group A (n = 254)	Group B (n = 307)	P value
Sex
Male	214 (84)	260 (85)	0.907
Female	40 (16)	47 (15)
Age (yr), median (range)	64 (39-81)	66 (41-86)	< 0.001
Baseline clinical TNM-stage
I	119 (47)	155 (50)	0.39
II	66 (26)	88 (29)	0.50
III	69 (27)	64 (21)	0.09
Treatment for primary ESCC
Surgery	84 (33)	124 (40)	0.079
Endoscopic resection	77 (30)	113 (37)	0.010
Chemoradiotherapy	93 (37)	70 (23)	0.001
Follow-up period
Median months (range)	60 (13-145)	67 (12-107)	0.150

ESCC: Esophageal squamous cell carcinoma.