Table 1.
Univariate analysis of risk factors influencing overall and disease-free survival
| Variable | n = 59 (%) | Overall survival | Disease-free survival | ||||
|---|---|---|---|---|---|---|---|
| HR | [95% CI] | P | HR | [95% CI] | P | ||
| General factors | |||||||
| Sex | |||||||
| Female | 26 (44) | 1 | 1 | ||||
| Male | 33 (56) | 3.780 | [1.367–13.290] | 0.009 | 2.076 | [1.018–4.480] | 0.045 |
| Age (years old) | |||||||
| ≥ 70 | 20 (34) | 1 | 1 | ||||
| < 70 | 39 (66) | 1.063 | [0.417–3.042] | 0.902 | 1.215 | [0.595–2.625] | 0.599 |
| Primary colorectal cancer related factors | |||||||
| Location | |||||||
| Colon | 34 (58) | 1 | 1 | ||||
| Rectum | 25 (42) | 2.524 | [0.991–6.877] | 0.052 | 1.725 | [0.854–3.483] | 0.127 |
| Histological type/differentiation | |||||||
| Well differentiated | 21 (36) | 1 | 1 | ||||
| Moderately/poorly differentiated or mucinous | 38 (64) | 1.757 | [0.634–6.188] | 0.295 | 1.053 | [0.520–2.273] | 0.889 |
| Preoperative serum CEA (ng/mL) | |||||||
| < 5.0 | 23 (39) | 1 | 1 | ||||
| ≥ 5.0 | 36 (61) | 1.822 | [0.660–6.400] | 0.262 | 1.571 | [0.751–3.586] | 0.238 |
| T stage | |||||||
| T1/T2/T3 | 34 (58) | 1 | 1 | ||||
| T4 | 25 (42) | 1.485 | [0.598–3.740] | 0.390 | 1.403 | [0.690–2.823] | 0.344 |
| N stage | |||||||
| N0/N1 | 50 (85) | 1 | 1 | ||||
| N2 | 9 (15) | 2.839 | [0.897–7.733] | 0.073 | 3.496 | [1.458–7.540] | 0.007 |
| Lymphatic invasion | |||||||
| Not identified | 19 (32) | 1 | 1 | ||||
| Identified | 40 (68) | 1.448 | [0.520–5.117] | 0.500 | 1.433 | [0.670–3.410] | 0.366 |
| Vascular invasion | |||||||
| Not identified | 12 (20) | 1 | 1 | ||||
| Identified | 47 (80) | 3.555 | [0.729–64.051] | 0.135 | 3.412 | [1.210–14.264] | 0.018 |
| pTNM stage | |||||||
| Stage 1/2 | 29 (49) | 1.351 | [0.531–3.397] | 1.022 | [0.506–2.065] | ||
| Stage 3/4 | 30 (51) | 1 | 0.520 | 1 | 0.949 | ||
| Adjuvant chemotherapy | |||||||
| Not performed | 28 (48) | 1 | 1 | ||||
| Performed | 31 (53) | 1.396 | [0.558–3.769] | 0.480 | 1.130 | [0.609–2.483] | 0.568 |
| Lung metastasis related factors | |||||||
| Number of tumors | |||||||
| Solitary | 48 (81) | 1 | 1 | ||||
| Multiple | 11 (19) | 1.496 | [0.482–3.928] | 0.456 | 1.908 | [0.801–4.081] | 0.136 |
| Tumor size (mm) | |||||||
| < 20 | 27 (46) | 1 | 1 | ||||
| ≥ 20 | 32 (54) | 1.985 | [0.779–5.674] | 0.154 | 1.591 | [0.786–3.360] | 0.199 |
| Tumor distribution | |||||||
| Unilateral | 51 (86) | 1 | 1 | ||||
| Bilateral | 8 (14) | 2.376 | [0.763–6.256] | 0.126 | 2.528 | [0.934–5.805] | 0.066 |
| Preoperative serum CEA (ng/mL) | |||||||
| < 5.0 | 36 (61) | 1 | 1 | ||||
| ≥ 5.0 | 23 (39) | 3.030 | [1.173–7.999] | 0.023 | 2.230 | [1.103–4.508] | 0.026 |
| Operative procedure | |||||||
| Lobectomy | 19 (32) | 1 | 1 | ||||
| Wedge resection/segmentectomy | 40 (68) | 1.911 | [0.691–6.721] | 0.225 | 1.049 | [0.509–2.320] | 0.899 |
| DFI after colorectal cancer resection (months) | |||||||
| ≥ 24 | 20 (34) | 1 | 1 | ||||
| < 24 | 39 (66) | 5.402 | [1.545–34.105] | 0.006 | 2.428 | [1.105–6.096] | 0.026 |
| Adjuvant chemotherapy | |||||||
| Not performed | 33 (56) | 1 | 1 | ||||
| Performed | 26 (44) | 1.916 | [0.772–4.974] | 0.160 | 1.461 | [0.725–2.945] | 0.285 |
| Liver metastasis related factor | |||||||
| History of hepatic metastasis | |||||||
| Absent | 31 (53) | 1 | 1 | ||||
| Present | 28 (48) | 1.616 | [0.647–4.356] | 0.307 | 1.249 | [0.620–2.518] | 0.530 |
CEA carcinoembryonic antigen, CI confidence interval, DFI disease-free interval, HR, hazard ratio