Table 3. Multivariate analysis of prognostic factors for locoregional recurrence-free survival.

Characteristic	Entire cohort			Without PMRT
	HR	95%CI	P	HR	95%CI	P
Tumor size (pT2 vs. pT1)	2.094	1.115–3.931	0.021	2.079	1.106–3.906	0.023
Positive lymph nodes, n (2–3 vs. 1)	2.092	1.251–3.499	0.005	2.073	1.238–3.472	0.006
Breast cancer subtype
(luminal B vs. luminal A)	1.064	0.524–2.159	0.864	1.078	0.532–2.187	0.835
(Her2 positive vs. luminal A)	2.863	1.568–5.229	0.001	2.732	1.480–5.040	0.001
(triple negative vs. luminal A)	1.929	0.952–3.907	0.068	1.936	0.956–3.922	0.067
PMRT (yes vs. no)	0.073	0.010–0.531	0.010

PMRT, postmastectomy radiotherapy; LNR, lymph node ratio; HR, hazard ratio; CI, confidence interval.