Table 4.

18q LOH and Patient Mortality in Non–MSI-High Colorectal Cancer in Strata of Tumor Stage

AJCC Tumor Stage	Total No.	HR for Colorectal Cancer–Specific Mortality in 18q LOH-Positive Patients*				HR for Overall Mortality in 18q LOH-Positive Patients*
		Univariate HR	95% CI	Multivariate HR	95% CI	Univariate HR	95% CI	Multivariate HR	95% CI
I to II	262	1.31	0.58 to 2.98	1.24	0.54 to 2.85	0.92	0.58 to 1.47	0.89	0.55 to 1.43
III	160	0.78	0.43 to 1.40	0.76	0.42 to 1.38	0.91	0.56 to 1.47	0.93	0.56 to 1.52
IV	82	0.93	0.58 to 1.48	1.35	0.80 to 2.28	0.89	0.55 to 1.42	1.34	0.80 to 2.25
Pfor interaction (18q LOH and stage)†		.32		.50		.86		.76

NOTE. The multivariate Cox regression model included the 18q LOH variable stratified by tumor stage, age, year of diagnosis, sex, family history of colorectal cancer, tumor location, tumor grade, KRAS, BRAF, PIK3CA,p53, β-catenin, JC virus T antigen, LINE-1 methylation, MSI (low v microsatellite stability), and CpG island methylator phenotype.

Abbreviations: LOH, loss of heterozygosity; MSI, microsatellite instability; AJCC, American Joint Committee on Cancer; HR, hazard ratio.

^*Versus 18q LOH-negative patients as a referent.

^†For assessing a potential interaction, tumor stage was dichotomized as I to II v III to IV.