Table 4.
Univariate and multivariate analyses for the factors associated with local control.
| Univariate Analysis | Multivariate Analysis | |||||
|---|---|---|---|---|---|---|
| Factors | n (%) | Number of Events | Hazard Ratio (95% CI) | p-Value | Hazard Ratio (95% CI) | p-Value |
| Age (y) | ||||||
| <80 | 68 (65.4%) | 7 | 1 | 0.855 | ||
| ≥80 | 36 (34.6%) | 3 | 1.135 (0.228–3.414) | |||
| Sex | ||||||
| Male | 71 (68.3%) | 9 | 1 | 0.12 | ||
| Female | 33 (31.7%) | 1 | 0.194 (0.652–40.721) | |||
| ECOG-PS | ||||||
| 0, 1 | 83 (79.8%) | 7 | 1 | 0.342 | ||
| 2–4 | 21 (20.2%) | 3 | 1.929 (0.497–7.487) | |||
| Smoking history | ||||||
| None | 22 (21.2%) | 3 | 1 | 0.586 | ||
| Any | 82 (78.8%) | 7 | 1.456 (0.377–5.633) | |||
| Operability | ||||||
| Operable | 19 (18.3%) | 1 | 1 | 0.508 | ||
| Inoperable | 85 (81.7%) | 9 | 2.010 (0.255–15.864) | |||
| Pathological diagnosis | ||||||
| Squamous cell carcinoma | 22 (21.2%) | 6 | 1 | 0.005 | 1 | 0.025 |
| other | 82 (78.8%) | 4 | 0.160 (0.045–0.567) | 0.228 (0.063–0.828) | ||
| Clinical T Stage | ||||||
| T1 | 64 (61.5%) | 3 | 1 | 0.033 | 1 | 0.042 |
| T2 | 40 (38.5%) | 7 | 4.369 (1.128–16.915) | 4.111 (1.054–16.042) | ||
| CTV margin | ||||||
| 0 mm (GTV = CTV) | 41 (39.4%) | 2 | 1 | 0.219 | ||
| ≥1 mm | 63 (60.6%) | 8 | 2.648 (0.560–12.527) | |||
| PTV volume | ||||||
| <40 cm3 | 57 (54.8%) | 3 | 1 | 0.068 | ||
| ≥40 cm3 | 47 (45.2%) | 7 | 3.536 (0.912–13.704) | |||
| Dmax (BED10, Gy) | ||||||
| <125 Gy | 36 (34.6%) | 8 | 1 | 0.021 | 1 | 0.041 |
| ≥125 Gy | 68 (65.4%) | 2 | 0.161(0.034–0.758) | 0.195 (0.040–0.945) | ||
| D50 (BED10, Gy) | ||||||
| <111 Gy | 37 (35.6%) | 7 | 1 | 0.053 | ||
| ≥111 Gy | 67 (64.4%) | 3 | 0.263 (0.068–1.017) | |||
| D95 (BED10, Gy) | ||||||
| <104 Gy | 42 (40.4%) | 7 | 1 | 0.121 | ||
| ≥104 Gy | 62 (59.6%) | 3 | 0.343 (0.089–1.328) | |||
| D98 (BED10, Gy) | ||||||
| <100 Gy | 35 (33.7%) | 5 | 1 | 0.473 | ||
| ≥100 Gy | 69 (66.3%) | 5 | 0.635 (0.183–2.195) | |||
| Dmin (BED10, Gy) | ||||||
| <95 Gy | 72 (69.2%) | 5 | 1 | 0.136 | ||
| ≥95 Gy | 32 (30.8%) | 5 | 2.579 (0.112–1.346) | |||
Abbreviations: CI, confidence interval; ECOG-PS, Eastern Cooperative Oncology Group Performance Status; Dmax, maximum dose; BED, biologically effective dose; Dx, dose to the x-percentage volume of the region of interest; Dmin, minimum dose; PTV, planning target volume; CTV, Clinical target volume; GTV, gross tumor volume.