Table 2.

Cox proportional hazards regression models estimating 5-year DFS and 5-year DSS.

Variable	HR	95% CI	P
Five-year DFS
Univariate analysis
T stage (T1, T2, T3, or T4)	1.234	1.125–1.353	<0.001
pN stage (N1, N2b, or N2c)	1.331	1.133–1.563	<0.001
Pathological grade (I, II, or III)	1.238	1.031–1.486	0.022
ECS (absence vs. presence)	1.990	1.493–2.651	<0.001
Number of positive lymph nodes (≤2 vs. >2)	1.809	1.469–2.228	<0.001
LNR (≤0.075 vs. >0.075)	1.639	1.329–2.021	<0.001
Multivariate survival analysis (forward method)
T stage (T1, T2, T3, or T4)	1.204	1.050–1.381	0.008
ECS (absence vs. presence)	1.754	1.307–2.353	<0.001
LNR (≤0.075 vs. >0.075)	1.644	1.220–2.216	0.001
Five-year DSS
Univariate analysis
Growth pattern (exophytic, ulcerative or infiltrative)	1.244	1.067–1.450	0.005
T stage (T1, T2, T3, or T4)	1.358	1.227–1.503	<0.001
pN stage (N1, N2b, or N2c)	1.525	1.281–1.815	<0.001
Pathological grade (I, II, or III)	1.307	1.073–1.593	0.008
ECS (absence vs. presence)	2.111	1.556–2.863	<0.001
Number of positive lymph nodes (≤2 vs. >2)	2.274	1.815–2.850	<0.001
LNR (≤0.075 vs. >0.075)	1.907	1.513–2.405	<0.001
Multivariate survival analysis (forward method)
T stage (T1, T2, T3, or T4)	1.263	1.066–1.497	0.007
ECS (absence vs. presence)	1.934	1.321–2.830	0.001
LNR (≤0.075 vs. >0.075)	1.740	1.206–2.511	0.003

Notes: LNR, lymph node ratio; pN stage, pathological node stage; ECS, extracapsular spread; RT, radiotherapy; CCRT, concurrent chemo-radiotherapy.