Table 4.
Univariate and multivariate analyses results
| Overall survival | Local recurrence-free survival | |||||
|---|---|---|---|---|---|---|
| Parameter | HR | 95% CI | P valuea | HR | 95% CI | P value |
| Univariate analysis | ||||||
| Age (≧60 vs < 60) | 1.113 | 0.635–1.950 | 0.708 | 1.583 | 0.787–3.185 | 0.198 |
| Histology (SCC vs non- SCC) | 2.651 | 1.048–6.706 | 0.040* | 1.969 | 0.598–6.491 | 0.265 |
| Hb (≦8 vs > 8) | 2.047 | 0.955–4.388 | 0.065 | 1.386 | 0.486–3.957 | 0.541 |
| SCC (≦10 vs > 10) | 0.756 | 0.422–1.354 | 0.347 | 0.953 | 0.471–1.930 | 0.894 |
| Tumor size (≧6 cm vs < 6 cm) | 1.700 | 0.964–2.998 | 0.067 | 2.593 | 1.291–5.205 | 0.007* |
| Stage (I + II vs III + IV) | 0.992 | 0.565–1.742 | 0.977 | 1.186 | 0.589–2.385 | 0.633 |
| EQD2 HR-CTV D90 | ||||||
| (≧70 Gy vs < 70 Gy) | 1.973 | 1.102–3.533 | 0.022* | 4.180 | 1.804–9.686 | <0.001* |
| OTT (<56 days vs ≧56 days) | 1.411 | 0.721–2.762 | 0.315 | 1.448 | 0.650–3.226 | 0.365 |
| Chemotherapy | ||||||
| Neoadjuvant (yes vs no) | 0.453 | 0.140–1.460 | 0.185 | 1.194 | 0.163–8.752 | 0.862 |
| Concurrent (≧4 Cycles vs no) | 0.499 | 0.279–0.895 | 0.020* | 0.656 | 0.324–1.328 | 0.241 |
| Adjuvant (yes vs no) | 0.888 | 0.492–1.601 | 0.693 | 0.816 | 0.399–1.669 | 0.577 |
| Multivariate analysis (stepwise method) | ||||||
| EQD2 HR-CTV D90 | ||||||
| (≧70 Gy vs < 70 Gy) | 2.015 | 1.125–3.608 | 0.019* | 4.664 | 1.985–10.96 | <0.001* |
| OTT (<56 days vs ≧56 days) | 1.994 | 0.882–4.509 | 0.098 | |||
| Chemotherapy | ||||||
| Concurrent (≧4 Cycles vs no) | 0.489 | 0.273–0.877 | 0.016* | |||
aCut off value for stepwise methods was set to P < 0.1. * Statistically significant (P < 0.05).
HR = Hazard ratio, CI = confidence interval, Hb = hemoglobin (g/dl), SCC = SCC antigen level (ng/ml), HR-CTV EQD2 = equivalent dose to 2 Gy of high risk CTV, OTT = overall treatment time.