Table 2.

Impact of tumor localization on the OS by univariate and multivariate survival analysis before PSM.

Characteristics		Univariate analysis		Multivariate analysis
		Log rank χ2	P value	HR	95% CI	P value
Tumor localization		49.4	<0.001
	DGC			Reference
	OGC			1.29	1.23-1.36	<0.001
	PGC			1.15	1.09-1.22	<0.001
Age		76.2	<0.001
	18-49			Reference
	50-59			1.01	0.84-1.22	0.886
	60-69			1.04	0.87-1.26	0.644
	70-79			1.72	1.41-2.11	<0.001
	≥80			1.71	1.35-2.17	<0.001
Race		12.3	0.007
	White			Reference
	Black			1.07	0.89-1.28	0.467
	API			0.89	0.75-1.06	0.192
	AI			1.12	0.57-2.20	0.733
Marital status		28.3	<0.001
	Divorced			Reference
	Married			0.98	0.81-1.19	0.858
	Widowed			1.04	0.81-1.34	0.758
	Single			1.08	0.86-1.35	0.508
Median household income		16.7	<0.001
	Quartile 1			Reference
	Quartile 2			0.91	0.81-1.02	0.102
	Quartile 3			1.06	0.94-1.19	0.319
	Quartile 4			0.89	0.79-1.00	0.047
TNM stage		437.0	<0.001
	I			Reference
	II			1.84	1.45-2.34	<0.001
	III			3.54	2.84-4.41	<0.001
	IV			4.22	3.34-5.32	<0.001
Tumor size		244.6	<0.001
	≤2			Reference
	≤5			1.47	1.14-1.88	0.002
	>5 cm			2.05	1.59-2.64	<0.001
	Unknown			2.01	1.57-2.58	<0.001
Regional node examined		122.1	<0.001
	≤16			Reference
	>16			0.83	0.70-0.99	0.041
Bone metastasis		81.6	<0.001
	Yes			Reference
	No			0.86	0.65-1.14	0.290
Liver metastasis		87.0	<0.001
	Yes			Reference
	No			0.88	0.68-1.13	0.309
Lung metastasis		74.3	<0.001
	Yes			Reference
	No			0.86	0.63-1.17	0.331
Surgery		527.7	<0.001
	No			Reference
	Yes			0.35	0.29-0.42	<0.001
Radiation		22.6	<0.001
	No/unknown		Reference
	Yes			0.98	0.84-1.14	0.801
Chemotherapy		11.0	<0.001
	No/unknown		Reference
	Yes			0.43	0.37-0.50	<0.001

OS: overall survival; PSM: propensity score matching; HR: hazard ratio; CI: confidence interval.