Table 4.

Multivariate analysis of overall and recurrence-free survival according to patient characteristics and treatment variables

Characteristic	Overall survival p-value	Overall survival HR (95% CI)	Recurrence-free survival p-value	Recurrence-free survival HR (95% CI)
Chemotherapy	0.017	0.426 (0.212–0.858)	0.002	0.248 (0.103–0.596)
Betel quid	0.004	3.951 (1.567–9.966)	NS	NS
Anemia	0.003	3.1 (1.488–6.461)	NS	NS
Pathological T4	NS	NS	0.016	0.355 (0.153–0.826)
Invasion depth ≥ 11 mm	0.007	0.187 (0.055–0.632)	< 0.001	0.077 (0.02–0.303)
Interval between surgery and PORT	NS	NS	0.003	3.872 (1.582–9.474)

Abbreviation: HR hazard ratio, CI confidence interval, PORT postoperative radiotherapy, NS not significant