S1. Multivariate Cox regression analyses of risk factors for CSS before PSM.

Variables	HR (95% CI)	P
CSS, cancer-specific survival; PSM, propensity score matching; T2DM, type 2 diabetes mellitus; HR, hazard ratio; 95% CI, 95% confidence interval.
T2DM (Yes vs. No)	1.070 (0.685−1.482)	0.685
Ascites (Yes vs. No)	1.760 (1.365−2.267)	<0.001
Gastrectomy		0.136
Proximal vs. Total	0.909 (0.677−1.222)	0.528
Distal vs. Total	0.850 (0.724−0.997)	0.046
Lymphadenectomy (D2/D2+ vs. others)	0.728 (0.500−1.059)	0.097
Radical Resection (Yes vs. No)	0.525 (0.361−0.764)	0.001
Grade		0.172
G3−4vs. G1−2	1.059 (0.867−1.293)	0.574
Unknown vs. G1−2	1.263 (0.973−1.639)	0.079
Vascular invasion (Yes vs. No)	1.112 (0.925−1.336)	0.258
Primary tumor invasion		<0.001
T2 vs. T1	2.083 (1.282−3.385)	0.003
T3 vs. T1	2.686 (1.661−4.342)	<0.001
T4 vs. T1	3.503 (2.385−5.146)	<0.001
Lymph node status		<0.001
N1 vs. N0	1.555 (1.194−2.024)	0.001
N2 vs. N0	2.266 (1.785−2.876)	<0.001
N3 vs. N0	3.751 (2.982−4.718)	<0.001
Metastasis (M1 vs. M0)	0.997 (0.681−1.461)	0.989
Tumor size (cm) (≥5 vs. <5)	1.098 (0.933−1.293)	0.261