Table 3. Univariate Kaplan-Meier and multivariate cox proportional hazard model for disease-free survival (DFS).
| Variable | No. of patients | Median survival (months) | Univariate, P value | Multivariate | |
|---|---|---|---|---|---|
| HR (95% CI) | P value | ||||
| Age | 0.793 | – | – | ||
| ≤65 | 120 | 15 | |||
| >65 | 86 | 20 | |||
| Gender | 0.836 | – | – | ||
| Female | 85 | 18 | |||
| Male | 121 | 17 | |||
| ASA status | 0.010 | ||||
| I-II | 56 | 24 | |||
| III-IV | 150 | 15 | 1.5 (1.0–2.3) | 0.044 | |
| Primary tumor | 0.08 | ||||
| Colon | 129 | 16 | 1.1 (0.6–1.1) | 0.479 | |
| Rectum | 77 | 21 | |||
| Metastases type | 0.031 | ||||
| Synchronous | 79 | 14 | 1.5 (1.0–2.1) | 0.019 | |
| Metachronous | 127 | 20 | |||
| No. of metastases | 0.027 | ||||
| ≤3 | 187 | 18 | |||
| >3 | 19 | 12 | 1.8 (0.9–3.1) | 0.071 | |
| Tumor size | 0.837 | – | – | ||
| <3 | 82 | 15 | |||
| 3–5 | 78 | 21 | |||
| >5 | 46 | 19 | |||
| Tumor location | 0.476 | – | – | ||
| Unilobar | 178 | 18 | |||
| Bilobar | 28 | 14 | |||
| Margin status | 0.318 | – | – | ||
| R0 | 157 | 19 | |||
| R1 | 49 | 14 | |||
| CEA (ng/mL) | 0.067 | ||||
| ≤10 | 98 | 21 | |||
| >10 | 108 | 15 | 1.4 (1.0–2.0) | 0.038 | |
| Resection type | 0.146 | – | – | ||
| Major | 73 | 15 | |||
| Minor | 133 | 21 | |||
| Preop chemotherapy | 0.141 | – | – | ||
| Yes | 166 | 16 | |||
| No | 40 | 34 | |||
| Postop chemotherapy | 0.997 | – | – | ||
| Yes | 120 | 16 | |||
| No | 86 | 18 | |||
| Surgical margin recurrence | <0.0001 | ||||
| Yes | 32 | 6.5 | 3.0 (1.9–4.5) | <0.0001 | |
| No | 174 | 22 | |||
| Blood transfusion | 0.227 | – | – | ||
| Yes | 29 | 15 | |||
| No | 177 | 18 | |||
Parameters showing a statistical significance P<0.10 on univariate analysis were entered into the multivariate model. HR, hazard ratio; CI, confidence interval; ASA, American Society of Anesthesiologist score; CEA, carcinoembriyogenic antigen.