TABLE III.
Univariate and Multivariable Analysis for Overall and Disease-Specific Survival.
| Characteristic | Univariate |
Multivariable |
||
|---|---|---|---|---|
| HR (95% CI) | P | HR (95% CI) | P | |
| Overall survival | ||||
| Age (continuous) | 1.02 (0.95-1.09) | .60 | ||
| AJCC stage (III vs. IV) | 0.52 (0.14-1.97) | .34 | ||
| Chemotherapy received (yes vs. no) | 1.75 (0.50-6.17) | .38 | ||
| ECS (positive vs. negative) | 0.92 (0.20-4.24) | .91 | ||
| Gender (male vs. female) | 0.62 (0.14-2.89) | .55 | ||
| ISH HPV (positive vs. negative) | 0.48 (0.12-1.96) | .31 | ||
| Margin (positive vs. negative) | 4.78 (1.39-16.42) | .01 | 3.83 (0.72-20.50) | .12 |
| N stage (N0–1 vs. N2–3) | 0.76 (0.29-1.97) | .57 | ||
| p16 (positive vs. negative) | 0.05 (0.01-0.22) | <.0001 | 0.04 (0.01-0.19) | <.0001 |
| RT received (yes vs. no) | 0.33 (0.07-1.53) | .16 | ||
| Site (BOT vs. tonsil) | 1.73 (0.50-5.99) | .38 | ||
| Smoking (yes vs. no) | 6.83 (0.87-53.37) | .07 | ||
| T stage (T3–4 vs. T1–2) | 2.03 (1.01-3.75) | .02 | 1.94 (0.88-4.32) | .10 |
| Disease-specific survival | ||||
| Age (continuous) | 1.02 (0.93-1.12) | .64 | ||
| AJCC stage (III vs. IV) | 0.98 (0.11-8.39) | .98 | ||
| Chemotherapy received (yes vs. no) | 3.19 (0.61-16.71) | .17 | ||
| ECS (positive vs. negative) | 0.98 (0.12-8.43) | .99 | ||
| Gender (male vs. female) | 0.28 (0.05-1.54) | .14 | ||
| ISH HPV (positive vs. negative) | 0.80 (0.08-7.59) | .84 | ||
| Margin (positive vs. negative) | 4.07 (0.74-22.48) | .11 | * | * |
| N stage (N0–1 vs. N2–3) | 2.07 (0.34-12.54) | .43 | ||
| p16 (positive vs. negative) | 0.087 (0.01-0.85) | .04 | 0.10 (0.01-0.98) | .05 |
| RT received (yes vs. no) | 0.36 (0.04-3.09) | .35 | ||
| Site (BOT vs. tonsil) | 1.96 (0.36-10.81) | .44 | ||
| Smoking (yes vs. no) | * | * | ||
| T stage (T3–4 vs. T1–2) | 2.14 (0.93-4.94) | .08 | 2.00 (0.66-6.07) | .22 |
*
Variable could not be analyzed with Cox proportional model due to absence of events in one or more groups.
HR = hazard ratio; CI = confidence interval; AJCC = American Joint Committee on Cancer; ECS = extracapsular spread; ISH = in situ hybridization; HPV = human papilloma virus; N stage = nodal stage; RT = radiotherapy; T stage = tumor stage; BOT = base of tongue.