Table 3.

Subgroup analysis of OS in terms of smoking history vs. no smoking history by the characteristics of patients in the entire population

No. of events/no. at risk
Factor5-year OS rate (%)P for OS by each factorNo smoking historySmoking historyAdjusted HR (95% CI)aP for smoking history vs. no smoking history
Overall82.2126/947252/9021.73 (1.32–2.27)<0.001
Age (year)<0.001
 ≤5286.483/723126/5891.79 (1.26–2.54)0.001
 >5271.843/224126/3132.02 (1.31–3.14)0.002
Gender<0.001
 Male80.465/509245/8891.69 (1.27–2.24)<0.001
 Female87.661/4387/131.75 (0.66–4.64)0.257
Drinking status0.017
 Yes77.87/3965/2401.78 (0.76–4.16)0.187
 No83.0119/908187/6621.79 (1.34–2.38)<0.001
VCA-IgA0.004
 ≤1:16084.753/46594/3731.77 (1.25–2.52)0.001
 >1:16080.173/482158/5291.78 (1.34–2.36)<0.001
Clinical stage<0.001
 I + II92.611/32037/2513.67 (1.54–8.77)0.003
 III + IV77.4115/627215/6511.76 (1.32–2.35)<0.001
Chemotherapy0.001
 Yes80.5104/722210/6941.74 (1.28–2.35)<0.001
 No87.522/22542/2082.10 (1.05–4.18)0.035
Radiation technique0.007
 IMRT/3DCRT86.923/26755/2282.08 (1.14–3.79)0.017
 Conventional80.4103/680197/6741.60 (1.18–2.17)0.003
  • aAdjusted for age (continuous), gender, drinking status, histological type, T-stage, N-stage, VCA-IgA titer (≤ and > 1:160), radiation techniques, and chemotherapy regimens.