Table 1.
Comparison of baseline data
| Factors | Normal group (n = 50) | Patient group (n = 78) | t / χ2 | P value |
| Gender | 0.161 | 0.688 | ||
| Male | 30 (60.00) | 44 (56.41) | ||
| Female | 20 (40.00) | 34 (43.59) | ||
| Age (yr) | 60.4 ± 4.8 | 58.7 ± 5.4 | 0.310 | 0.757 |
| Smoking history | 0.295 | 0.587 | ||
| Yes | 30 (60.00) | 43 (55.13) | ||
| No | 20 (40.00) | 35 (44.87) | ||
| History of alcoholism | 0.081 | 0.776 | ||
| Yes | 8 (16.00) | 14 (17.95) | ||
| No | 42 (84.00) | 64 (82.05) | ||
| Location | ||||
| The upper thoracic area | 19 (24.36) | |||
| The middle thoracic area | 34 (43.59) | |||
| The lower thoracic area | 25 (32.05) | |||
| Tumor size | ||||
| ≥ 3 cm | 45 (57.69) | |||
| < 3 cm | 33 (42.31) | |||
| Differentiation | ||||
| Low differentiation | 25 (32.05) | |||
| Moderate + high differentiation | 53 (67.95) | |||
| TNM stage | ||||
| Stage I | 27 (34.62) | |||
| Stage II + III | 51 (65.38) |