Table 2. Univariate analysis for DFS and OS among perioperative variables.
| Variables | Number of Patients | P value (DFS) | P value (OS) |
|---|---|---|---|
| Sex | 0.86 | 0.510 | |
| Male | 47 | ||
| Female | 32 | ||
| Site of primary tumour | 0.14 | 0.370 | |
| Colon | 36 | ||
| Rectum | 43 | ||
| Stage of primary tumour | <0.01 | 0.850 | |
| I–III | 56 | ||
| IV | 23 | ||
| Number of lung metastasis | <0.01 | 0.110 | |
| Solitary | 49 | ||
| Multiple | 30 | ||
| Location of lung metastasis | <0.001 | 0.120 | |
| Unilateral | 58 | ||
| Bilateral | 21 | ||
| Preoperative serum CEA level (ng/mL) | <0.001 | <0.001 | |
| ≤5 | 51 | ||
| >5 | 28 | ||
| Disease-free interval (months) | 0.01 | 0.025 | |
| ≤24 | 59 | ||
| >24 | 20 | ||
| History of liver metastasis | <0.01 | 0.046 | |
| None | 43 | ||
| Present | 36 |
CEA, carcinoembryonic antigen; DFS, disease-free survival; CTC, circulating tumour cell.