Table 2 Univariate and multivariate analyses for occurrence of grade ≥ 2 radiation pneumonitis.
Factors | n = 52 | (%) | Univariate analysis | Multivariate analysis | ||
|---|---|---|---|---|---|---|
Hazard ratio (95% CI) | P-value | Hazard ratio (95% CI) | P-value | |||
Age (years) | ||||||
< 65 | 7 | 14% | 1 | 0.62 | ||
≥ 65 | 45 | 87% | 0.73 (0.24–3.12) | |||
Gender | ||||||
Male | 38 | 73% | 1 | 0.39 | ||
Female | 14 | 27% | 1.52 (0.57–3.71) | |||
ECOG-PS | ||||||
0 | 28 | 54% | 1 | 0.87 | ||
≥ 1 | 24 | 46% | 0.93 (0.37–2.24) | |||
Brinkman index | ||||||
< 500 | 11 | 21% | 1 | 0.39 | ||
≥ 500 | 41 | 79% | 1.66 (0.56–7.11) | |||
Laterality of the primary tumor | ||||||
Left | 28 | 54% | 1 | 0.07 | ||
Right | 24 | 46% | 2.29 (0.95–5.85) | |||
Location of the treated tumor | ||||||
Other lobe | 35 | 67% | 1 | 0.08 | ||
Lower lobe | 17 | 33% | 2.24 (0.90–5.43) | |||
Previous pneumonectomy | ||||||
No | 41 | 79% | 1 | 0.64 | ||
Yes | 11 | 21% | 1.28 (0.42–3.31) | |||
Concurrent chemotherapy | ||||||
Yes | 49 | 94% | 1 | 0.08 | ||
No | 3 | 6% | not applicable | |||
Maintenance ICI | ||||||
Yes | 40 | 77% | 1 | 0.92 | ||
No | 12 | 23% | 0.95 (0.37–2.93) | |||
PTV | ||||||
< 270 cc | 17 | 33% | 1 | < 0.01 | 1 | 0.60 |
≥ 270 cc | 35 | 67% | 5.69 (1.64–35.84) | 0.49 (0.02–7.54) | ||
Total lung volume | ||||||
> 3260 cc | 22 | 42% | 1 | 0.06 | ||
≤ 3260 cc | 30 | 58% | 2.47 (0.96–7.61) | |||
V20 (total lung) | ||||||
< 17% | 20 | 39% | 1 | < 0.01 | 1 | 0.33 |
≥ 17% | 32 | 62% | 16.85 (3.48–303.28) | 4.37 (0.17–115.69) | ||
V5 (total lung) | ||||||
< 40% | 22 | 42% | 1 | < 0.01 | 1 | 0.02 |
≥ 40% | 30 | 58% | 21.74 (4.49–391.07) | 9.80 (1.48–200.94) | ||
Dmean (total lung) | ||||||
< 11 Gy | 25 | 48% | 1 | < 0.01 | 1 | 0.61 |
≥ 11 Gy | 27 | 52% | 12.84 (3.67–81.10) | 2.15 (0.11–92.67) | ||
IMRT | ||||||
VMAT | 31 | 60% | 1 | 0.02 | 1 | 0.25 |
HT | 21 | 40% | 0.31 (0.09–0.86) | 0.53 (0.14–1.52) | ||
