TABLE 4.
Multivariate analysis of risk factors for symptomatic pneumonitis (By forward‐stepwise regression test)
| Factors | OR (95% CIs) | p value | Beta coefficient |
|---|---|---|---|
| Pulmonary emphysema | 5.67 (1.66–19.37) | 0.006 | 1.735 |
| V20 (<16.7%/≥16.7%) | 3.49 (1.41–8.66) | 0.007 | 1.250 |
| Smoking history (<40/≥40 pack years) | – | 0.376 | – |
| PTV/LV (<0.08/≥0.08) | – | 0.308 | – |
| Time from the initiation of PD‐(L)1 inhibitor treatment to TRT (<4.8/≥4.8 months) | – | 0.076 | – |
Abbreviations: CIs, confidence intervals; LV, total lungs volume; OR, Odds ratio; PD‐(L)1, programmed death 1/programmed death ligand 1; PTV, planning target volume; TRT, thoracic radiotherapy; Vx, percentage of the total lung volume receiving no less than x Gy of radiation.