Table 1. Patient demographics and risk factors in colorectal cancer.
| Characteristics | Case (N=527) | Control (N=639) | P |
| Age | 56.46±11.70 | 56.00±10.59 | 0.490 |
| Gender | 0.733 | ||
| Female | 215(40.8%) | 267(41.8%) | |
| Male | 312(59.2%) | 372(58.2%) | |
| Smoking | 0.371 | ||
| Yes | 286(54.3%) | 330(51.6%) | |
| No | 241(45.7%) | 309(48.4%) | |
| Drinking | 0.156 | ||
| Yes | 308(58.4%) | 347(54.3%) | |
| No | 219(41.6%) | 292(45.7%) | |
| Family history of cancer | 0.106 | ||
| Yes | 65(12.3%) | 100(15.6%) | |
| No | 462(88.4%) | 539(84.7%) | |
| Tumor size | |||
| <5cm | 306(58.1%) | — | |
| ≥5cm | 221(41.9%) | — | |
| CEA | |||
| Positive | 143(27.1%) | — | |
| Negative | 384(72.9%) | — | |
| CA199 | |||
| Positive | 152(28.8%) | — | |
| Negative | 375(71.2%) | — | |
| Tumor location | |||
| Rectum | 303(57.5%) | — | |
| Colon | 224(42.5%) | — | |
| Differentiation | |||
| Well | 244(58.3%) | — | |
| Moderate | 204(41.7%) | — | |
| Poor | 79(59.3%) | — | |
| Adenocarcinoma | |||
| Yes | 301(57.1%) | — | |
| No | 226(42.9%) | — | |
| TNM classification | |||
| I | 65(16.9%) | — | |
| II | 197(34.0%) | — | |
| III | 162(41.0%) | — | |
| IV | 103(8.1%) | — |
CEA: carcino-embryonic antigen; CA199: carbohydrate antigen 19-9; TNM: tumor node metastasis.