Table 2.
Univariable and multivariable survival analysis
| Univariable survival analysis | Multivariable analysis | Multivariable analysis | |||||
|---|---|---|---|---|---|---|---|
| NSCLC + SCLC cohort | NSCLC + SCLC cohort | NSCLC-only cohort | |||||
| N = 422, E = 367 | N = 327, E = 284 | ||||||
| Covariat | N (E) | Hazard ratio (95% confidence interval) | P-value | Hazard ratio (95% confidence interval) | P-value | Hazard ratio (95% confidence interval) | P-value |
| Sex | |||||||
| Female (reference) | 925 (816) | 1 | 1 | 1 | |||
| versus male | 1.14 (0.99–1.31) | 0.06 | 1.03 (0.83–1.27) | 0.82 | 0.95 (0.74–1.22) | 0.67 | |
| Age | 925 (816) | 1.00 (1.00–1.01) | 0.35 | 1.00 (0.99–1.01) | 0.85 | 0.99 (0.98–1.01) | 0.48 |
| Performance status | |||||||
| Good (0–1) versus mid (2) versus poor (3–4) | 925 (816) | 1.32 (1.21–1.45) | <0.001 | 1.22 (1.05–1.42) | 0.01 | 1.25 (1.05–1.49) | 0.01 |
| Histology | |||||||
| Adenocarcinoma (reference) | 925 (816) | 1 | 1 | 1 | |||
| versus adenosquamous | 1.25 (0.59–2.65) | 0.56 | 1.51 (0.55–4.17) | 0.42 | 1.54 (0.56–4.26) | 0.41 | |
| versus large cell | 0.68 (0.36–1.28) | 0.24 | 0.91 (0.42–2.01) | 0.82 | 0.84 (0.38–1.87) | 0.67 | |
| versus squamous cell | 1.00 (0.85–1.18) | 0.98 | 1.06 (0.83–1.36) | 0.62 | 1.08 (0.84–1.39) | 0.56 | |
| versus small cell | 0.80 (0.68–0.96) | 0.02 | 0.76 (0.56–1.01) | 0.06 | NA | NA | |
| Comorbidities | |||||||
| 0 versus 1 versus 2 versus 3 | 776 (673) | 1.09 (1.02–1.18) | 0.02 | 1.06 (0.94–1.18) | 0.34 | 1.08 (0.94–1.23) | 0.27 |
| Combined TNM stage | |||||||
| IV (reference) | 721 (642) | 1 | 1 | 1 | |||
| versus III | 0.89 (0.74–1.08) | 0.23 | 0.98 (0.75–1.28) | 0.87 | 1.05 (0.76–1.43) | 0.78 | |
| versus I+II | 1.03 (0.63–1.67) | 0.92 | 0.74 (0.38–1.44) | 0.38 | 0.70 (0.33–1.49) | 0.36 | |
| Tumour location | |||||||
| Lower lobe (reference) | 823 (720) | 1 | 1 | 1 | |||
| versus middle lobe | 0.87 (0.64–1.17) | 0.35 | 1.83 (0.79–4.23) | 0.16 | 1.37 (0.49–3.79) | 0.55 | |
| versus upper lobe | 0.93 (0.80–1.11) | 0.46 | 0.90 (0.71–1.14) | 0.36 | 0.87 (0.67–1.14) | 0.32 | |
| Tumour side | |||||||
| Left (reference) | 763 (669) | 1 | 1 | 1 | |||
| versus right | 0.99 (0.85–1.15) | 0.88 | 1.04 (0.83–1.29) | 0.75 | 0.98 (0.76–1.25) | 0.85 | |
| Smoking status | |||||||
| Current smoker (reference) | 766 (663) | 1 | 1 | 1 | |||
| versus light former | 0.88 (0.36–2.14) | 0.78 | 0.42 (0.13–1.39) | 0.16 | 0.43 (0.13–1.43) | 0.17 | |
| versus ex-smoker | 0.92 (0.78–1.08) | 0.31 | 0.95 (0.75–1.21) | 0.69 | 0.98 (0.74–1.29) | 0.88 | |
| versus lifelong never | 0.57 (0.37–0.89) | 0.01 | NA∗ | NA∗ | NA∗ | NA∗ | |
| Pack years | 691 (598) | 1.00 (1.00–1.01) | 0.4 | 1.00 (0.99–1.00) | 0.59 | 1.00 (0.99–1.00) | 0.30 |
| Fractionation scheme | |||||||
| 30 Gy/10F versus 20 Gy/5F versus 8 + 10 Gy/1F | 925 (816) | 1.73 (1.56–1.91) | <0.001 | 1.48 (1.23–1.77) | <0.001 | 1.54 (1.25–1.89) | <0.001 |
| Primary radiotherapy technique | |||||||
| IMRT (reference) | 925 (816) | 1 | 1 | ||||
| versus parallel pair and two field | 2.03 (0.29–14.41) | 0.48 | 2.03 (0.28–14.86) | 0.49 | 2.30 (0.31–17.05) | 0.42 | |
| versus single field | 2.13 (0.29–15.74) | 0.46 | 2.03 (0.25–16.50) | 0.51 | 2.23 (0.27–18.30) | 0.46 | |
| versus 3+ field | 1.64 (0.19–14.06) | 0.65 | 1.54 (0.16–15.15) | 0.71 | 1.83 (0.18–18.15) | 0.61 | |
IMRT, intensity-modulated radiotherapy; N, number of patients; E, number of events.
∗
There were no lifelong never smokers when performing a complete case analysis.