Table 1.
Baseline characteristics of the study population.
| Characteristics | No Radiotherapy (n (n%)) | Radiotherapy (n (n%)) | P |
|---|---|---|---|
| Total (N = 679) | 231 | 448 | |
| Age (year) | |||
| <65 | 148 (64.1) | 333 (74.3) | 0.007 |
| ≥65 | 83 (35.9) | 115 (25.7) | |
| Gender | |||
| Male | 174 (75.3) | 335 (74.8) | 0.950 |
| Female | 57 (24.7) | 113 (25.2) | |
| Race | |||
| White | 115 (49.8) | 191 (42.6) | 0.278* |
| Black | 30 (13.0) | 74 (16.5) | |
| Other | 85 (36.8) | 181 (40.4) | |
| Unknown | 1 (0.4) | 2 (0.5) | |
| Year of diagnosis | |||
| 1988–2003 | 82 (34.5) | 177 (39.5) | 0.349 |
| 2004–2012 | 149 (65.5) | 271 (60.5) | |
| Grade | |||
| Grade I | 4 (1.8) | 6 (1.3) | 0.065* |
| Grade II | 21 (9.1) | 34 (7.6) | |
| Grade III | 77 (33.3) | 174 (38.8) | |
| Grade IV | 50 (21.6) | 123 (27.5) | |
| Unknown | 79 (34.2) | 111 (24.8) | |
| Histology | |||
| Squamous cell carcinoma | 105 (45.5%) | 188 (42.0%) | 0.315 |
| Non-keratinizing carcinoma | 30 (13.0%) | 82 (18.3%) | |
| Undifferentiated carcinoma | 40 (17.3%) | 81 (18.1%) | |
| Unknown | 56 (24.2%) | 97 (21.6%) | |
| Surgery | |||
| No surgery | 209 (90.5) | 392 (87.5) | 0.318* |
| Surgery | 22 (9.5) | 52 (11.6) | |
| Unknown | 0 | 4 (0.9) | |
*Fisher’s exact test was used.