Relationships among KRAS mutation status, expression of RAS pathway signaling molecules, and clinicopathological features and prognosis of patients with colorectal cancer

Table 3 Relationship between KRAS and BRAF protein expression and clinicopathological features of colorectal cancer patients

General data		KRAS protein			BRAF protein
		Positive rate (%)	χ²	P-value	Positive rate (%)	χ²	P-value
Median age (yr)	< 56	71 (57/80)	5.34	0.02	77.6 (52/67)	0.10	0.76
	≥ 56	65.9 (83/126)			79.5 (101/127)
Gender	Male	74.3 (84/123)	1.11	0.29	79.5 (89/112)	0.06	0.81
	Female	64.5 (56/83)			78.0 (64/82)
Differentiation	Medium-low	71.6 (106/148)	10.8	0.001	75.7 (106/140)	3.23	0.08
	Well	70.8 (34/48)			87.0 (47/54)
Infiltration depth	T1+T2	63.2 (24/38)	0.21	1.52	79.9 (111/139)	0.28	0.59
	T3+T4	73.4 (116/158)			76.4 (42/55)
Lymph node metastasis	N0	69.6 (64/92)	0.29	0.59	75.0 (69/92)	0.024	0.878
	N1-N3	73.1 (76/104)			74.0 (77/104)
Distant metastasis	M0	70.2 (106/151)	0.49	0.49	75.9 (107/141)	2.96	0.10
	M1	75.6 (34/45)			86.8 (46/53)
TNM stage	Stage I	64 (16/25)	0.79	0.85	75.0 (18/24)	5.98	0.11
	Stage II	71.9 (41/57)			69.5 (41/59)
	Stage III	72.63 (51/70)			82.9 (58/70)
	Stage IV	72.2 (32/44)			87.8 (36/41)