Table 5.
Correlation between risk factors and RP using binary logistic regression analysis
| Factors | Grade ≥ 2 RP | Grade ≥ 3 RP | ||||
|---|---|---|---|---|---|---|
| Odds ratio (OR) | 95% CI | p value | OR | 95% CI | p value | |
| MLD (≥ 12.0 Gy vs. < 12.0 Gy) | 2.480 | 1.006–6.113 | 0.049 | – | – | – |
| Tumor located in lower lobe | 2.311 | 0.898–5.943 | 0.082 | – | – | – |
| Chemotherapy with gemcitabine in the past | – | – | – | 3.209 | 1.018–10.113 | 0.046 |
| V5 (≥ 50%vs. < 50%) | – | – | – | 3.429 | 1.056–11.140 | 0.040 |
| Percentage of lung volume affected in subclinical ILD ≥ 25% | – | – | – | 4.861 | 1.237–19.104 | 0.024 |
RP, radiation pneumonitis; MLD, mean lung dose; V5, percentage of lung volume receiving ≥ 5 Gy; ILD, interstitial lung disease; CI, confidence interval