HER2 heterogeneity is a poor prognosticator for HER2-positive gastric cancer

Table 2 Prognostic factors for overall survival and progression-free survival

Covariates	Overall survival				Progression-free survival
	Univariate analysis		Multivariable analysis		Univariate analysis		Multivariable analysis
	HR (95%CI)	P-value	HR (95%CI)	P-value	HR (95%CI)	P-value	HR (95%CI)	P-value
Age, ≥ 80 vs < 80	1.31 (0.473-3.625)	0.604			1.138 (0.492-2.633)	0.762
Sex, female vs male	1.057 (0.621-1.798)	0.838			1.005 (0.615-1.642)	0.985
Macroscopic type, type 3,4 vs 1,2	1.72 (1.027-2.881)	0.039			1.641 (1.037-2.598)	0.034
Clinical tumor depth, cT4 vs ≤ cT3	1.838(0.992-3.405)	0.053			1.408 (0.826-2.401)	0.209
Clinical nodal status, cN3 vs ≤ cN2	2.026 (1.184-3.466)	0.01	2.119 (1.165-3.855)	0.014	1.691 (1.056-2.708)	0.029	1.622 (0.951-2.764)	0.076
Histology, undiff. vs diff.	1.884 (1.090-3.255)	0.023	2.612 (1.388-4.916)	0.003	1.643 (1.031-2.618)	0.037	1.902 (1.117-3.237)	0.018
HER2 score, 2+ vs 3+	2.331 (1.353-4.016)	0.002	2.008 (1.094-3.690)	0.024	1.828 (1.110-3.012)	0.018	1.612 (0.940-2.770)	0.083
HER2 heterogeneity, hetero vs homo	2.439 (1.389-4.274)	0.002	3.115 (1.610-6.024)	0.001	2 (1.203-3.333)	0.008	2.123 (1.225-3.676)	0.007
No. of non-curative factors, ≥ 2 vs 1	1.904 (1.138-3.186)	0.014	2.252 (1.113-4.553)	0.024	1.875 (1.185-2.965)	0.007	1.871 (1.023-3.424)	0.042
M1, lymph node	0.687 (0.410-1.150)	0.154			0.568 (0.358-0.902)	0.017
M1, peritoneal	1.207 (0.699-2.086)	0.5			1.327 (0.828-2.127)	0.24
M1, hepatic	1.902 (1.141-3.173)	0.014	2.084 (1.076-4.036)	0.029	1.974 (1.244-3.132)	0.004	2.053 (1.151-3.664)	0.015

HER2: Human epidermal growth factor receptor 2; HR: Hazard ratio.