Table 1.
Characteristics of study participants: newly diagnosed lung cancer (LC) patients and patients with chronic obstructive pulmonary disease (COPD).
| Discovery and verification set (n = 100) | Validation set (n = 55) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| LC patients (n = 50) | COPD patients (n = 50) | LC patients (n = 28) | COPD patients (n = 27) | ||||||
| Current smokers | Former smokers | Current smokers | Former smokers | Current smokers | Former smokers | Current smokers | Former smokers | ||
| N | 25 | 25 | 25 | 25 | 13 | 15 | 10 | 17 | |
| Age, years | Mean ± SD | 63 ± 6.4 | 67 ± 5.2 | 61 ± 5.8 | 69 ± 8.3 | 64 ± 6.6 | 66 ± 3.4 | 63 ± 8.2 | 67.8 ± 10.4 |
| Median | 62 | 68 | 61 | 70 | 65 | 65 | 63 | 66 | |
| Sex, n | Female | 7 | 8 | 8 | 7 | 3 | 6 | 4 | 2 |
| Male | 18 | 17 | 17 | 18 | 10 | 9 | 6 | 15 | |
| BMI, kg/m2 | Mean ± SD | 25.2 ± 4.5 | 26.9 ± 3.9 | 28.2 ± 6.8 | 26.4 ± 4.9 | 24.9 ± 4.0 | 26.0 ± 5.1 | 24.7 ± 9.1 | 30.4 ± 6.2 |
| Median | 25.6 | 27.5 | 27.3 | 26.3 | 25.4 | 25.2 | 22.1 | 32.3 | |
| Smoking intensity, packyears | Mean ± SD | 41.7 ± 13.0 | 29.3 ± 18.9 | 39.5 ± 13.4 | 30.3 ± 13.5 | 38.1 ± 15.5 | 24.9 ± 8.7 | 42.8 ± 20.4 | 46.2 ± 16.1 |
| Median | 40 | 27 | 40 | 32 | 40 | 20 | 43 | 48 | |
| Smoking cessation time, years | 2–5 years | n/a | 9 | n/a | 6 | n/a | 5 | n/a | 4 |
| 6–10 years | n/a | 5 | n/a | 6 | n/a | 1 | n/a | 3 | |
| 11–15 years | n/a | 8 | n/a | 6 | n/a | 5 | n/a | 5 | |
| > 15 years | n/a | 3 | n/a | 7 | n/a | 4 | n/a | 5 | |
|
Clinical stage according to TNM classification, 7th ed, n |
I | 13 | 11 | n/a | n/a | 6 | 6 | n/a | n/a |
| II | 8 | 6 | n/a | n/a | 4 | 5 | n/a | n/a | |
| III | 4 | 8 | n/a | n/a | 1 | 4 | n/a | n/a | |
| Unspecified | – | – | n/a | n/a | 2 | – | n/a | n/a | |
| Histology, n | Adenocarcinoma | 11 | 10 | n/a | n/a | 5 | 8 | n/a | n/a |
| Squamous-cell carcinoma | 12 | 15 | n/a | n/a | 7 | 7 | n/a | n/a | |
| Other or unspecified | 2 | – | n/a | n/a | 1 | – | n/a | n/a | |