Table 1.
Characteristics of the cases and controls
| Characteristics | Case (%) | Control (%) | P value |
|---|---|---|---|
| Gender | |||
| Male | 216 (51.3%) | 207 (48.7%) | 0.45 |
| Female | 205 (48.7%) | 218 (51.3%) | |
| Age (years) | |||
| ≤ 60 | 210 (49.9%) | 230 (54.1%) | 0.22 |
| > 60 | 211 (50.1%) | 195 (45.9%) | |
| Smoking status | |||
| No | 224 (53.2%) | 231 (54.3%) | 0.74 |
| Yes | 197 (46.8%) | 194 (45.7%) | |
| Histology | |||
| Squamous cell carcinoma | 267 (63.4%) | ||
| Adenocarcinoma | 154 (36.6%) | ||
| TNM stage | |||
| I + II | 139 (33.0%) | ||
| III + IV | 282 (67.0%) | ||
| HWE | 0.369 | 0.595 |
TNM, tumour-node-metastasis staging system; HWE, Hardy-Weinberg equilibrium.