Factors associated with overall survival in early gastric cancer patients who underwent additional surgery after endoscopic submucosal dissection

Table 2 Independent risk factors for overall survival

Characteristic	Univariable analysis			Multivariable analysis
	HR	95%CI	P value	HR	95%CI	P value
Age (yr)
< 60	Reference	-	-	Reference	-	-
≥ 60	1.152	0.119-11.174	0.902
Sex (male)	13.550	1.407-130.515	0.024	21.906	3.762-229.250	0.039
Tumor location
Upper stomach	Reference	-	-	Reference	-	-
Middle stomach	2.740	0.563-13.340	0.212
Lower stomach	2.124	0.417-13.101	0.197
Tumor size (cm)
< 2	Reference	-	-	Reference	-	-
≥ 2	0.222	0.031-18.579	0.133
Gross type
Protruded	Reference	-	-	Reference	-	-
Flat	0.000	0.000	0.984
Pitting	1.440	0.149-27.959	0.753
Invasion depth
T1a	Reference	-	-	Reference	-	-
T1b	2.011	0.621-6.213	0.018	3.965	1.109-17.432	0.047
Histological type
Differentiated	Reference	-	-	Reference	-	-
Undifferentiated	13.155	0.991-25.014	0.028	9.455	0.946-29.482	0.049
Number of tumor lesions
Solitary	Reference	-	-	Reference	-	-
Multiple	0.912	0.301-9.761	0.781
Positive vascular invasion	0.818	0.169-8.965	0.803
Lauren classification
Intestinal type	Reference	-	-	Reference	-	-
Diffuse	1.683	0.518-15.468	0.386
Mixed	0.968	0.512-14.129	0.571
Pattern of invasion
IFN-A	Reference	-	-	Reference	-	-
IFN-B	0.545	0.080-33.730	0.537
IFN-C	9.899	1.159-19.526	0.036
Positive horizontal resection margin	0.989	0.164-45.987	0.990
Positive vertical resection margin	29.109	0.172-353.649	0.353
Positive nerve invasion	1.000	0.10-102.816	> 0.999
eCura score
Low-risk group	Reference	-	-	Reference	-	-
Moderate-risk group	0.938	0.126-27.910	0.810
High-risk group	0.994	0.108-10.192	0.715
Degree of radical endoscopic treatment (eCura)
eCura-A	Reference	-	-	Reference	-	-
eCura-B	0.997	0.000	> 0.999
eCura-C1	0.812	0.101-15.171	0.969
eCura-C2	1.745	0.257-11.846	0.569
Ulcer	0.829	0.134-13.122	0.840
Range of lymph node dissection
D1	Reference	-	-	Reference	-	-
D2	4.066	0.421-39.278	0.225
Lymph node metastasis	1.813	0.390-3.871	0.003	2.126	0.002-13.266	0.031
Residual tumor	5.160	2.391-9.107	0.021	4.275	1.049-27.420	0.043

HR: Hazard ratio; CI: Confidence interval.