Table 1.
Clinical characteristics of cases and controls
| Characteristics | Cases (%) | Controls (%) | P values |
|---|---|---|---|
| Total | 706 | 745 | |
| Age (years) | 61.2±9.2 | 60.6±9.9 | 0.177 |
| Sex, % male | 495 (70.1) | 502 (67.4) | 0.282 |
| Pathologic type | |||
| medullary | 268 (38.0) | ||
| ulcerative | 278 (39.4) | ||
| others | 113 (16.0) | ||
| unknown | 47 (6.7) | ||
| Histologic grade | |||
| well | 60 (8.5) | ||
| moderate | 378 (53.5) | ||
| poor | 247 (35.0) | ||
| unknown | 21 (3.0) | ||
| Tumor size (cm) | |||
| > 4.5 | 235 (33.3) | ||
| ≤ 4.5 | 340 (48.2) | ||
| unknown | 131 (18.6) | ||
| TNM | |||
| I | 35 (5.0) | ||
| II | 304 (43.1) | ||
| III | 252 (35.7) | ||
| IV | 78 (11.0) | ||
| unknown | 37 (5.2) | ||
| LNM | |||
| yes | 379 (53.7) | ||
| no | 294 (41.6) | ||
| unknown | 33 (4.7) |