Comparison of involved-field intensity-modulated radiotherapy combined with S-1 vs radiotherapy alone for elderly patients with esophageal cancer

Table 1 Baseline characteristics, n (%)

Variables	Total (n = 34)	CRT (n = 17)	Radiation (n = 17)	P value
Age (yr)				0.275
Median (range)	76.0 (72.0-80.0)	77.0 (75.0-80.0)	75.0 (72.0-80.0)
Age				0.731
≤ 75 yr	16 (47.1)	7 (41.2)	9 (52.9)
> 75 yr	18 (52.9)	10 (58.8)	8 (47.1)
Gende				1.000
Female	5 (14.7)	3 (17.6)	2 (11.8)
Male	29 (85.3)	14 (82.4)	15 (88.2)
Primary tumor location				1.000
Cervical	3 (8.8)	1 (5.9)	2 (11.8)
Distal third	14 (41.2)	7 (41.2)	7 (41.2)
Middle third	11 (32.4)	6 (35.3)	5 (29.4)
Proximal third	6 (17.6)	3 (17.6)	3 (17.6)
cTNM stage				0.282
II	12 (35.3)	4 (23.5)	8 (47.1)
III	22 (64.7)	13 (76.5)	9 (52.9)
Gastric tube insertion				1.000
No	23 (67.6)	11 (64.7)	12 (70.6)
Yes	11 (32.4)	6 (35.3)	5 (29.4)
Follow-up (mo)				0.293
Median (IQR)	24.5 (15.2-32.5)	26.0 (19.0-36.0)

All normally distributed and skewed continuous variables are described as medians with interquartile. For baseline characteristics analysis, the statistical differences among the quartiles of radiation were tested with one-way analysis of variance for continuous variables and via χ² tests for categorical variables. Statistical significance was set at P < 0.05. CRT: Concurrent chemoradiotherapy; IQR: Interquartile range.