Table 1.

Univariate and multivariable Cox regression analysis for prediction of OS.

Parameter		At risk group	HR [95% CI]	p-value
Univariate analysis
Gender		Male (vs Female)	1.68 [0.97, 2.89]	0.064
Age		Continuous	0.99 [0.97, 1.02]	0.545
ECOG Performance status		1 (vs 0)	1.77 [0.77, 4.08]	0.179
		>=2 (vs))	4.34 [1.72, 10.96]	0.002
ORR		Response (vs no response)	0.31 [0.13, 0.76]	0.010
Metastasis	Number of metastatic sites	>=2 sites (vs <2 sites)	1.31 [0.66, 2.62]	0.44
	Liver metastasis	Yes (vs No)	3.05 [1.70, 5.51]	<0.001
	Lung metastasis	Yes (vs No)	0.77 [0.35, 1.67]	0.505
	Other sites	Yes (vs No)	1.61 [0.68, 3.83]	0.283
WCC$		Continuous	1.18 [1.11, 1.25]	<0.001
Neutrophils$		Continuous	1.19 [1.11, 1.26]	<0.001
Lymphocytes		Continuous	0.72 [0.46, 1.12]	0.143
LDH		Continuous	1.001 [1.000, 1.003]	0.003
Ca 19.9 (Log2)		Continuous	1.07 [0.99, 1.16]	0.091
CNA		Continuous	7.09 [3.19, 15.78]	<0.001
Mutational burden	Number of mutations$	Continuous	1.06 [1.01, 1.12]	0.028
	Number of KRAS mutations$	Continuous	1.11 [1.07, 1.16]	<0.001
	KRAS mutations present	Yes (vs No)	3.46 [1.76, 6.77]	<0.001
	KRAS copy number gain	Yes (vs No)	10.94 [3.85, 31.08]	<0.001
	Highest VAF	Continuous	1.07 [1.04, 1.10]	<0.001
Multivariable analysis
ECOG Performance status		1 (vs 0)	2.51 [0.98, 6.38]	0.053
		>=2 (vs 0)	4.20 [1.48, 11.94]	0.007
Metastasis	Liver metastasis	Yes (vs No)	2.83 [1.28, 6.24]	0.010
Mutational burden	KRAS copy number gain	Yes (vs No)	3.47 [1.19, 10.17]	0.023
	Highest VAF	Continuous	1.05 [1.01, 1.08]	0.005

Abbreviations: ORR, objective response rate (clinical outcome variable); VAF: variant allele frequency; ECOG, Eastern Cooperative Oncology Group; WCC: white cell count; $, Excluded from stepwise model building due to collinearity.