Table 5.
Comparison of treatment characteristics of definitive RT cohort
| Treatment characteristics | HVC | LVC | MVA | |
|---|---|---|---|---|
| n (%) | n (%) | P value | OR (95% CI) | |
| RT duration (wk) | ||||
| ≤7 | 466 (46) | 62 (30) | <0.001 | REF |
| >7 | 546 (54) | 136 (65) | <0.001 | 0.49 (0.31‐0.77) |
| Unknown duration | 6 (1) | 12 (6) | 0.036 | 0.19 (0.04‐0.9) |
| Total RT dose | ||||
| <66/60 Gy | 59 (6) | 22 (11) | <0.001 | REF |
| ≥66/60 Gy | 955 (94) | 145 (69) | 0.031 | 2.36 (1.08‐5.12) |
| Unknown dose | 4 (0) | 43 (21) | <0.001 | 0.11 (0.03‐0.47) |
| IMRT | ||||
| IMRT (−) | 272 (27) | 29 (14) | <0.001 | REF |
| IMRT (+) | 690 (68) | 60 (29) | 0.694 | 0.9 (0.53‐1.52) |
| Unknown IMRT status | 56 (6) | 121 (58) | <0.001 | 0.07 (0.04‐0.12) |
| Chemotherapya | ||||
| Chemo (−) | 232 (23) | 57 (27) | — | — |
| Chemo (+) | 786 (77) | 153 (73) | ||
| DTI (d)a | ||||
| ≤45 | 497 (49) | 92 (44) | — | — |
| 46+ | 521 (51) | 118 (56) | ||
95%CI, 95% confidence interval; DTI, diagnosis to treatment initiation; HVC, high‐volume center; HPV, human papillomavirus; IMRT, intensity‐modulated radiotherapy; LVC, low‐volume center; MVA, multivariate analysis; n, number of patients; OR, odds ratio; REF, reference variable; RT, radiation.
a
Not included on MVA.