Table I.
Characteristics of lung cancer cases and healthy controls.
| Cases (n=762) | Controls (n=700) | ||
|---|---|---|---|
|
|
|
||
| Variable | n (%) | n (%) | P-value |
| Gender | <0.001a | ||
| Male | 472 (61.9) | 326 (46.6) | |
| Female | 290 (38.1) | 374 (53.4) | |
| Age, years | <0.001b | ||
| Mean ± SD | 68.4±9.8 | 64.1±12.7 | |
| Range | 31–95 | 20–93 | |
| MDM2 polymorphism | 0.69a | ||
| T/T | 153 (20.1) | 152 (21.7) | |
| T/G | 379 (49.7) | 335 (47.9) | |
| G/G | 230 (30.2) | 213 (30.4) | |
| G allele frequency | 0.551 | 0.544 | |
| PY | |||
| Mean ± SD | 36.4±37.2 | 26.6±32.7 | 0.001b |
| Range | 0–265 | 0–184 | |
| Histology | |||
| AD | 487 (63.9) | ||
| SQ | 182 (23.9) | ||
| Others | 82 (10.8) | ||
| Un-differentiated | 11 (1.4) | ||
a
Pearson’s χ2 test.
b
Kruskal-Wallis test.
SD, standard deviation; MDM2, murine double minute 2; PY, pack-years; AD, adenocarcinoma; SQ, squamous cell carcinoma.