Table 3. Multivariate Cox regression model analysis of factors in predicting PFS.
| Parameter | No. of patients (%) | HR | 95% CI | P |
|---|---|---|---|---|
| Age (years) | 1.143 | 0.603–2.167 | 0.681 | |
| ≥65 | 18 (19.6) | |||
| <65 | 74 (80.4) | |||
| Sex | 0.702 | 0.422–1.168 | 0.173 | |
| Female | 44 (47.8) | |||
| Male | 48 (52.2) | |||
| ECOG PS | 0.686 | 0.348–1.353 | 0.277 | |
| 0–1 | 80 (87.0) | |||
| 2 | 12 (13.0) | |||
| Primary tumor site | 0.856 | 0.519–1.411 | 0.541 | |
| Left colon | 61 (66.3) | |||
| Right colon | 28 (30.4) | |||
| With liver metastasis | 1.112 | 0.686–1.800 | 0.667 | |
| Yes | 53 (57.6) | |||
| No | 39 (42.4) | |||
| Number of metastatic sites | 0.965 | 0.594–1.566 | 0.884 | |
| <3 | 48 (52.2) | |||
| ≥3 | 44 (47.8) | |||
| Treatment line | 1.315 | 0.825–2.094 | 0.249 | |
| 3 | 43 (46.7) | |||
| ≥4 | 49 (53.3) | |||
| KRAS | 1.523 | 0.871–2.663 | 0.140 | |
| Wild type | 57 (62.0) | |||
| Mutant | 35 (38.0) | |||
| NRAS | 0.517 | 0.224–1.195 | 0.123 | |
| Wild type | 84 (91.3) | |||
| Mutant | 8 (8.7) | |||
| BRAF | 2.260 | 0.887–5.757 | 0.088 | |
| Wild type | 86 (93.5) | |||
| Mutant | 6 (6.5) | |||
| Previous bevacizumab | 1.347 | 0.768–2.364 | 0.298 | |
| Yes | 58 (63.0) | |||
| No | 34 (37.0) | |||
| Previous cetuximab | 1.499 | 0.808–2.781 | 0.199 | |
| Yes | 26 (28.3) | |||
| No | 66 (71.7) |
PFS, progression-free survival; HR, hazard ratio; CI, confidence interval; ECOG PS, Eastern Cooperative Oncology Group performance status.