Different oncological features of colorectal cancer codon-specific KRAS mutations: Not codon 13 but codon 12 have prognostic value

Table 4 Cox regression analyses of recurrence-related factors in subgroups based on tumor location in the colon and rectum

	Colon (n = 1503)		Rectum (n = 700)
	HR (95%CI)	P value	HR (95%CI)	P value
Preoperative CEA ≥ 5.0 ng/mL	1.290 (0.860-1.933)	0.218	1.215 (0.705-2.220)	0.444
Diverting stoma (+)	0.903 (0.394-2.067)	0.809	1.249 (0.755-2.065)	0.386
T3-4 stage (vs T0-2)	1.211 (0.737-1.991)	0.450	1.079 (0.601-1.939)	0.799
N1-2 stage (vs N0)	1.241 (0.863-1.784)	0.244	1.126 (0.649-1.954)	0.674
Tumor size (cm)	1.100 (1.011-1.198)	0.027	1.077 (0.948-1.223)	0.256
Lymphatic invasion	1.342 (0.919-1.960)	0.128	0.971 (0.562-1.676)	0.915
Vascular invasion	1.981 (1.362-2.880)	< 0.001	1.401 (0.841-2.334)	0.195
Perineural invasion	1.793 (1.200-2.679)	0.004	3.358 (1.885-5.983)	< 0.001
Metastatic LN	1.048 (1.014-1.083)	0.006	1.095 (1.017-1.178)	0.016
KRAS Codon 12 mutation	1.496 (1.019-2.196)	0.040	1.492 (0.902-2.466)	0.119
KRAS Codon 13 mutation	0.831 (0.412-1.678)	0.606	0.481 (0.146-1.578)	0.227
KRAS Codon 61 mutation	2.385 (0.730-7.795)	0.150	2.270 (0.511-10.088)	0.282

KRAS: Kirsten rat sarcoma viral oncogene homolog; HR: Hazard ratio; CI: Confidence interval; CEA: Carcinoembryonic antigen; MSI: Microsatellite instability; MSS: Microsatellite stable; LN: Lymph node.