Table 3. Multivariate analysis for survival outcomes.

Variable	LRRFS			RFS			OS
	p-value	HR	95% CI	p-value	HR	95% CI	p-value	HR	95% CI
MRI (none vs. done)	0.818	0.814	0.141–4.704	0.528	0.075	0.307–1.832	0.818	1.187	0.277–5.087
Age ( < 50 yr vs. ≥ 50 yr)	0.093	4.197	0.789–22.338	0.307	1.477	0.699–3.122	0.299	2.032	0.533–7.744
T stage (T1 vs. T2)	0.048	5.012	1.014–24.783	0.001	3.639	1.643–8.063	0.049	4.358	1.005–18.890
Nodal status (negative vs. positive)	0.979	0.000001	-	0.470	0.694	0.258–1.869	0.294	0.322	0.039–2.671
ER (negative vs. positive)	0.648	1.519	0.253–9.134	0.085	0.440	0.173–1.119	0.726	0.747	0.146–3.815
Grade (I/II vs. III)	0.174	1.868	0.759–4.596	0.272	1.297	0.815–2.064	0.061	2.439	0.961–6.194

LRRFS=locoregional recurrence-free survival; RFS=recurrence-free survival; OS=overall survival; HR=hazard ratio; CI=confidence interval; MRI=magnetic resonance imaging; ER=estrogen receptor.