Table 3.
Univariate analysis of possible risk factors associated with the development of Grade ≥3 RP.
| Risk factors | Non-small cell lung cancer (n = 153) | Non-squamous cell carcinoma (n = 60) | Squamous cell carcinoma (n = 93) | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| RP <G3 (n%) | RP ≥G3 (n%) | P-value | RP <G3 (n%) | RP ≥G3 (n%) | P-value | RP <G3 (n%) | RP ≥G3 (n%) | P-value | ||
| Gender | Male | 125 | 15 | >0.999 | 44 | 5 | >0.999 | 81 | 10 | >0.999 |
| Female | 12 | 1 | 10 | 1 | 2 | 0 | ||||
| Age | 62.29 ± 8.90 | 68.56 ± 9.46 | 0.009 | 62.76 ± 9.52 | 68.83 ± 7.36 | 0.307 | 61.99 ± 8.51 | 68.40 ± 10.91 | 0.032 | |
| Tumor location | Upper | 77 | 10 | 0.847 | 27 | 3 | 0.692 | 50 | 7 | 0.765 |
| Middle | 26 | 3 | 11 | 2 | 15 | 1 | ||||
| Lower | 34 | 3 | 16 | 1 | 18 | 2 | ||||
| Smoking history | Yes | 84 | 10 | 0.927 | 28 | 3 | >0.999 | 56 | 7 | >0.999 |
| No | 53 | 6 | 26 | 3 | 27 | 3 | ||||
| Chemotherapy | Concurrent | 21 | 1 | 0.559 | 9 | 0 | 0.304 | 12 | 1 | 0.641 |
| Sequence 1a | 109 | 14 | 41 | 5 | 68 | 9 | ||||
| Sequence 2b | 7 | 1 | 4 | 1 | 3 | 0 | ||||
| PE Grade | 0 | 82 | 3 | 0.006 | 35 | 2 | 0.112 | 47 | 1 | 0.007 |
| 1 | 37 | 8 | 14 | 4 | 23 | 4 | ||||
| ≥2 | 18 | 5 | 5 | 0 | 13 | 5 | ||||
| FEV1/FVC % | ≥70 | 65 | 6 | 0.450 | 27 | 3 | >0.999 | 38 | 3 | 0.540 |
| <70 | 72 | 10 | 27 | 3 | 45 | 7 | ||||
| FVC | ≥2.8 | 72 | 6 | 0.254 | 25 | 3 | >0.999 | 47 | 3 | 0.208 |
| <2.8 | 65 | 10 | 29 | 3 | 36 | 7 | ||||
| PO2 | 83.97 ± 11.71 | 79.94 ± 6.72 | 0.179 | 82.19 ± 12.86 | 80.67 ± 6.19 | 0.307 | 85.13 ± 10.81 | 79.50 ± 7.31 | 0.113 | |
| PCO2 | 37.54 ± 4.27 | 35.98 ± 3.05 | 0.158 | 37.38 ± 4.26 | 35.82 ± 2.89 | 0.103 | 37.64 ± 4.30 | 36.07 ± 3.30 | 0.269 | |
| V5 | 49.25 ± 7.75 | 51.06 ± 6.17 | 0.368 | 49.37 ± 8.02 | 51.00 ± 1.10 | 0.010 | 49.17 ± 7.62 | 51.10 ± 7.92 | 0.453 | |
| V20 | 22.27 ± 3.98 | 24.06 ± 3.84 | 0.089 | 22.11 ± 4.12 | 24.00 ± 3.74 | 0.562 | 22.37 ± 3.91 | 24.10 ± 4.09 | 0.192 | |
| MLD | 11.93 ± 2.64 | 13.09 ± 2.39 | 0.098 | 12.07 ± 2.78 | 12.17 ± 2.49 | 0.882 | 11.85 ± 2.56 | 13.64 ± 2.27 | 0.037 | |
RP: radiation pneumonitis; G2, grade 2; G3, grade 3; PE, pulmonary emphysema; FEV1, forced expiratory volume in one second; FVC, forced vital capacity; PO2, arterial partial pressure of oxygen; PCO2, arterial partial pressure of carbon dioxide; V5, V20, the percentages of pulmonary volume irradiation exceeding 5 Gy, 20 Gy; MLD, mean lung dose. aSequence 1, patients who received chemotherapy first. bSequence 2, patients who received radiation therapy first. Significant differences are indicated in bold.