Correction: Feasibility of Elective Nodal Irradiation (ENI) and Involved Field Irradiation (IFI) in Radiotherapy for the Elderly Patients (Aged ≥ 70 Years) with Esophageal Squamous Cell Cancer: A Retrospective Analysis from a Single Institute.

There is an error in Table 2. Subheadings are missing from the first column. Please see the corrected Table 2 here.

Table 2

Univariate and multivariate analysis of the effect of prognostic factors on OS in patients with esophageal cancer.

Factors	Univariate analysis					Multivariate analysis
	1-y OS (%)	3-y OS (%)	5-y OS (%)	χ2	p	HR	95% CI	p
Sex
Male	55.0	20.8	12.5	1.467	0.226
Female	73.7	26.9	0
Tumor stage
T1-3	64.7	28.4	7.6	4.529	0.033	1.60	1.028–2.495	0.037
T4	57.1	0	0
LN status
N0	60.6	32.8	10.9	1.245	0.264
N+	63.5	20.2	4.7
Location
Cervical	90.9	23.4	11.7	2.252	0.133
Thoracic	60.3	23.2	5.1
Tumor length (cm)
≤ 5	64.9	31.7	5.6	2.209	0.154
> 5	60.3	16.0	5.7
RT dose (Gy)
≥ 60	65.7	27.7	5.3	0.293	0.588
< 60	60.0	19.0	6.3
KPS score
≥ 80	60.0	19.0	6.3	0.293	0.588
< 80	65.7	27.7	5.3
Smoking status
Yes	69.4	22.8	3.5	0.066	0.797
No	55.4	22.9	9.2
Treatment strategies
RT alone	63.9	21.2	4.7	0.422	0.936
CCRT	57.1	32.1	6.9
C+RT	64.0	17.5	8.8
RT+C	80.0	0	0
Irradiation field
ENI	68.5	26.4	10.3	1.319	0.251
IFI	59.0	21.7	0