Table 4.

Univariate analysis of relapse-free survival for immunohistochemical biomarkers in the test and validation sets

Set	Biomarker	+/-	n/total	n	Median RFS, years (95% CI)	HR (95% CI)	P
Test	ER	-	308/313	100	2.9 (1.7–4.1)	1
		+		208	6.1 (4.1–8.1)	0.70 (0.52–0.93)	0.02
	PR	-	279/313	143	3.0 (2.1–3.8)	1
		+		136	8.2 (5.0–11.4)	0.58 (0.43–0.78)	0.0003
	HER2	-	300/313	240	6.0 (4.4–7.6)	1
		+		60	3.6 (2.1–5.1)	1.33 (0.94–1.89)	0.1
	EGFR	-	271/313	239	6.0 (4.0–8.0)	1
		+		32	1.6 (0.9–2.3)	2.30 (1.49–3.56)	0.0002
	Ki-67	-	308/313	140	11.0 (6.5–15.6)	1
		+		168	3.6 (2.8–4.4)	1.93 (1.44–2.60)	0.00001
	p53	-	307/313	235	6.4 (4.3–8.6)	1
		+		72	2.6 (1.9–3.3)	1.59 (1.16–2.18)	0.004
	CA IX	-	281/313	234	5.7 (4.0–7.4)	1
		+		47	2.5 (1.4–3.6)	1.81 (1.26–2.62)	0.002
	CK5/6	-	260/313	238	5.2 (3.8–6.6)	1
		+		22	2.5 (0.6–4.3)	1.60 (0.94–2.73)	0.08
Validation	ER	-	288/289	100	2.6 (1.5–3.8)	1
		+		188	7.2 (5.8–8.5)	0.68 (0.50–0.92)	0.01
	PR	-	268/289	143	3.8 (2.1–5.5)	1
		+		125	7.2 (6.1–8.3)	0.73 (0.54–1.00)	0.05
	HER2	-	273/289	206	7.0 (5.8–8.2)	1
		+		67	2.4 (1.5–3.2)	1.55 (1.11–2.18)	0.01
	EGFR	-	257/289	219	6.6 (4.9–8.3)	1
		+		38	2.1 (1.3–2.8)	1.81 (1.21–2.70)	0.004
	Ki-67	-	289/289	134	7.2 (5.6–8.8)	1
		+		155	4.8 (3.0–6.6)	1.27 (0.94–1.70)	0.12
	p53	-	286/289	223	6.7 (5.1–8.2)	1
		+		63	2.7 (0.5–4.9)	1.40 (0.99–1.97)	0.06
	CA IX	-	271/289	227	7.1 (5.4–8.6)	1
		+		44	2.3 (1.3–3.2)	1.79 (1.23–2.61)	0.002
	CK5/6	-	252/289	237	6.0 (4.3–7.6)	1
		+		15	2.4 (1.7–3.1)	1.81 (1.00–3.27)	0.05

ER, estrogen receptor; PR, progesterone receptor; HER2, human epidermal growth factor receptor 2; EGFR, human epidermal growth factor receptor 1; CA IX, carbonic anhydrase IX; CK5/6, cytokeratin 5/6; RFS, relapse-free survival; CI, confidence interval; HR, hazard ratio; P, significance for comparison of hazard ratio.