Table 4. Analysis of different prognostic factors with overall survival (OS) and recurrence-free survival (RFS), according to Cox proportional hazards regression analysis.
| Cox Regression Analysis | Variables | Overall survival | Recurrence-Free survival | |||||
|---|---|---|---|---|---|---|---|---|
| HR | (95% CI) | P | HR | (95% CI) | P | |||
| Univariate Analysis | Sex | 0.604 | [0.271-1.347] | 0.218 | 0.673 | [0.338-1.337] | 0.258 | |
| Age | 1.009 | [0.977-1.042] | 0.579 | 1.819 | [1.051-3.148] | 0.033 | ||
| Smoking | 1.527 | [0.896-2.603] | 0.120 | 1.224 | [0.745-2.011] | 0.426 | ||
| Alcohol | 1.533 | [1.090-2.156] | 0.014 | 1.121 | [0.795-1.580] | 0.515 | ||
| Tumor EBV status | 1.101 | [0.622-1.947] | 0.742 | 1.014 | [0.593-1.733] | 0.959 | ||
| EBV viral load* | 1.041 | [0.737-1.472] | 0.818 | 0.924 | [0.704-1.375] | 0.984 | ||
| Tumor HCMV status | 1.369 | [0.492-3.814] | 0.548 | 1.441 | [0.574-3.617] | 0.437 | ||
| Histological grade | 1.305 | [0.908-1.875] | 0.150 | 1.348 | [0.947-1.920] | 0.097 | ||
| Nuclear grade | 1.185 | [0.847-1.657] | 0.321 | 1.525 | [1.113-2.088] | 0.009 | ||
| Tumor size | 1.315 | [1.089-1589] | 0.004 | 1.151 | [0.960-1.379] | 0.128 | ||
| Nodal status | 2.346 | [1.199-4.594] | 0.013 | 1.936 | [1.082-3.466] | 0.026 | ||
| Stage | 1.565 | [1.177-2.082] | 0.002 | 1.373 | [1.101-1.,712] | 0.005 | ||
| Recurrence | 8.560 | [3.782-19.37] | 0.000 | - | - | - | ||
| EBI3 | ht vs. wt | 0.948 | [0,488-1.843] | 0.875 | 0.866 | [0.465-1.613] | 0.650 | |
| rs4740 | mt vs. wt | 0.933 | [0.438-1.987] | 0.858 | 1.045 | [0.522-2.091] | 0.901 | |
| EBI3 | ht vs. wt | 0.742 | [0382-1.440] | 0.378 | 0.763 | [0.421-1.385] | 0.374 | |
| rs4905 | mt vs. wt | 1.344 | [0.629-2.871] | 0.446 | 1.248 | [0.592-2.633] | 0.561 | |
| EBI3 | ht vs. wt | 1.171 | [0.647-2.119] | 0.602 | 1.180 | [0.687-2.029] | 0.549 | |
| rs428253 | mt vs. wt | 2.312 | [0.698-7.657] | 0.170 | 2.026 | [0.616-6.662] | 0.245 | |
| Multivariate analysis | Stage | 2.590 | [1.622-4.137] | 0.0001 | 1.812 | [1.281-2.564] | 0.001 | |
| Recurrence | 7.996 | [3.49-18.327] | 0.00001 | - | - | - | ||
HR - Hazard ratio. Confidence interval.
* EBV viral load categories were defined as negative, low (below the median), and high (above the median), based on values calculated as 2(–ΔCt) x 200,000/10⁵ cells.