Table 4. Multivariate analysis of factors associated with overall survival after recurrence^*.

Variables	HR(95%CI)	P-value
HPV tumor status (Positive vs. negative)	0.23(0.09-0.58)	0.002
Age at diagnosis (per year)	1.04(0.99-1.09)	0.062
Race (White vs. non-white^)	0.57(0.23-1.44)	0.24
Smoking history (Ever vs. never)	0.72(0.33-1.61)	0.43
Initial nodal stage (2b-3 vs. 0-2a)	0.91(0.35-1.61)	0.84
Time to recurrence (≥1 year vs. <1 year)	0.36(0.18-0.74)	0.006
Site of recurrence (Locoregional vs. distant)	2.31(0.83 -6.39)	0.11
Number of recurrences (Multiple vs. single)	3.27(1.07-10.01)	0.038
Primary treatment (Surgical vs. non-surgical)	0.21(0.066-0.65)	0.007
Salvage treatment (Surgical vs. non-surgical)	0.26(0.12-0.61)	0.002

^*Restricted to patients who received salvage therapy (n=92). HR=Hazard ratio, CI=confidence interval.

^{^}Black and other