Table 2.
Univariate cox regression model in the training cohort.
| Variables | OS | P value | CSS | P value |
|---|---|---|---|---|
| HR (95% CI) | HR (95% CI) | |||
| Age at diagnose (years) | ||||
| < 77 | Reference | Reference | ||
| ≥ 77 | 2.473 (1.907, 3.206) | 0.000 | 1.450 (1.037, 2.027) | 0.030 |
| Sex | ||||
| Male | Reference | Reference | ||
| Female | 0.898 (0.628, 1.286) | 0.559 | 1.017 (0.651, 1.590) | 0.940 |
| Race | ||||
| Black | Reference | Reference | ||
| White | 1.347 (0.555, 3.270) | 0.510 | 0.752 (0.308, 1.838) | 0.532 |
| Other | 0.493 (0.132, 1.836) | 0.292 | 0.364 (0.087, 1.524) | 0.167 |
| Grade | ||||
| I–II | Reference | Reference | ||
| III–IV | 1.036 (0.800, 1.342) | 0.788 | 1.106 (0.791, 1.548) | 0.555 |
| Laterality | ||||
| Left | Reference | Reference | ||
| Right | 1.231 (0.954, 1.588) | 0.109 | 1.118 (0.805, 1.551) | 0.507 |
| Distant metastasis | ||||
| No | ||||
| Yes | 2.706 (1.433, 5.110) | 0.002 | 3.979 (2.019, 7.844) | 0.000 |
| AJCC stage | ||||
| I–II | Reference | Reference | ||
| III–IV | 1.867 (1.319, 2.642) | 0.000 | 2.559 (1.541, 4.248) | 0.000 |
| Type of surgery | ||||
| Total or radical parotidectomy | Reference | Reference | ||
| Local parotidectomy | 0.625 (0.477, 0.817) | 0.001 | 0.560 (0.392, 0.799) | 0.001 |
| Radiotherapy | ||||
| No | Reference | Reference | ||
| Yes | 0.771 (0.588, 1.011) | 0.060 | 0.939 (0.655, 1.347) | 0.733 |
| Chemotherapy | ||||
| No | Reference | Reference | ||
| Yes | 1.103 (0.816, 1.492) | 0.522 | 1.319 (0.910, 1.912) | 0.143 |
| Regional nodes examined | ||||
| < 23 | Reference | Reference | ||
| ≥ 23 | 1.230 (0.942, 1.605) | 0.128 | 1.256 (0.893, 1.766) | 0.190 |
| Regional nodes positive | ||||
| < 4 | Reference | Reference | ||
| ≥ 4 | 1.574 (1.146, 2.163) | 0.005 | 2.125 (1.465, 3.082) | 0.000 |
| Tumor size (mm) | ||||
| <28 | Reference | Reference | ||
| ≥ 28 | 1.878 (1.438, 2.452) | 0.000 | 1.879 (1.329, 2.656) | 0.000 |