Evaluation of malignancy using Ki-67, p53, EGFR and COX-2 expressions in gastrointestinal stromal tumors

Table 3 Multivariate analyses for disease-specific survival

Variable	RR (95% CI)	P value
Risk of malignancy
Very low/low risk	1.00 (reference)	< 0.001
Intermediate risk	1.32 (0.81-21.2)
High risk	12.23 (1.61-92.81)
Ki-67 expression
0+	1.00 (reference)	< 0.001
1+	3.75 (0.97-14.54)
2+	15.78 (4.25-59.37)
P53 expression
0+	1.00 (reference)	0.20
1+	2.11 (0.24-18.37)
2+	4.49 (0.54-37.11)
EGFR expression
0+	1.00 (reference)	0.50
1+	1.97 (0.60-6.50)
2+	1.17 (0.36-3.77)
COX-2 expression
0+	1.00 (reference)	0.19
1+	0.84 (0.42-4.36)
2+	1.99 (0.55-7.21)

EGFR: Epidermal growth factor receptor; COX-2: Cyclooxygenase-2; RR: Relative risk.