Table 4. Univariate analysis of all patients by Kaplan-Meier method.
| Variable | n | 5-Year survival rate (%) | P value |
| Gender | 0.936 | ||
| Female | 140 | 63 | |
| Male | 302 | 64 | |
| Age (y) | 0.386 | ||
| ≤50 | 113 | 61 | |
| >50 | 329 | 64 | |
| Tumor size (cm) | 0.001 | ||
| <6 | 390 | 66 | |
| ≥6 | 52 | 47 | |
| Tumor location | 0.032 | ||
| Upper third | 101 | 63 | |
| Middle third | 65 | 57 | |
| Lower third | 253 | 67 | |
| ≥Two thirds | 23 | 50 | |
| Histological type | 0.134 | ||
| Well-differentiated | 84 | ||
| Moderately-differentiated | 71 | ||
| Poorly-differentiated | 59 | ||
| Undifferentiated | 73 | ||
| Depth of invasion | 0.017 | ||
| Shallow muscularis layer | 263 | 66 | |
| Deep muscularis layer | 179 | 60 | |
| Vascular tumor emboli | 0.066 | ||
| Yes | 105 | 55 | |
| No | 337 | 66 | |
| Nervous invasion | 0.857 | ||
| Yes | 67 | 61 | |
| No | 375 | 64 | |
| Lymph node metastasis | 0.000 | ||
| Yes | 203 | 48 | |
| No | 239 | 77 | |
| Curability | 0.000 | ||
| Curative | 414 | 67 | |
| Palliative | 28 | 20 | |
| Pathological stage | 0.000 | ||
| IB (T2N0M0) | 239 | 77 | |
| IIA (T2N1M0) | 91 | 59 | |
| IIB (T2N2M0) | 65 | 42 | |
| IIIA (T2N3M0) | 47 | 35 |