Table 3. Univariate and multivariate Cox regression analyses by EGFR expression levels.

EGFR status	Mean time to recurrence (months)	Percentage of recurrence (95% confidence interval)	Hazard ratio (95% confidence interval)	P
Univariate
Local recurrence
Overexpressor	35.0	48.1% (38–64)	6.112 (1.3–22.1)	0.011
Nonoverexpressor	49.0	34.0% (30–46)	0.135 (0.03–0.5)
Disease-free survival
Overexpressor	24.2	59.2% (40–79)	2.786 (1.3–5.8)	0.005
Nonoverexpressor	36.7	16% (11–29)	0.323 (0.3–0.6)
Overall survival
Overexpressor	26.2	55.5% (34–79)	2.550 (1.2–4.7)	0.023
Nonoverexpressor	39.5	19.8% (14–30)	0.398 (0.2–0.8)
Multivariate
Variable	Hazard ratio	95% confidence interval		P
Local recurrence
Tumour type	1.556	0.7–3.5	—	0.25
TNM stage	1.398	0.7–2.6	—	0.25
Histologic grade	0.889	0.5–1.3	—	0.80
EGFR overexpressor	5.377	1.1–20.5	—	0.025*
Disease-free survival
Tumour type	1.557	0.8–2.8	—	0.11
TNM stage	1.559	1.1–2.5	—	0.08
Histologic grade	1.110	0.9–1.9	—	0.79
EGFR overexpressor	2.599	1.2–6.1	—	0.012*
Overall survival
Tumour type	1.559	0.8–3.5	—	0.15
TNM stage	1.450	1.3–2.7	—	0.011*
Histologic grade	0.999	0.9–1.8	—	0.84
EGFR overexpressor	2.568	1.2–5.9	—	0.041*

EGFR=epidermal growth factor receptor; TNM=tumour node metastasis.

^*Significant at the 0.05 level.