Table 1.
Training set (n=230) | Validation set (n=98) | χ2 | P | |
---|---|---|---|---|
Age (years) | ||||
≥65 | 133 | 51 | 0.934 | 0.334 |
<65 | 97 | 47 | ||
Sex | ||||
Male | 53 | 24 | 0.080 | 0.777 |
Female | 177 | 74 | ||
BMI (kg/m2) | ||||
≥23 | 179 | 80 | 0.599 | 0.439 |
<23 | 51 | 18 | ||
Operation mode | ||||
Open surgery | 80 | 37 | 0.265 | 0.607 |
Laparoscopic surgery | 150 | 61 | ||
Pathological type | ||||
Adenocarcinoma | 207 | 85 | 0.75 | 0.387 |
Squamous carcinoma | 23 | 13 | ||
Tumor size | ||||
≥3 cm | 127 | 57 | 0.242 | 0.623 |
<3 cm | 103 | 41 | ||
T-staging | ||||
T1b | 41 | 17 | 0.833 | 0.659 |
T2 | 115 | 54 | ||
T3 | 74 | 27 | ||
Lymph node metastasis | ||||
With | 92 | 43 | 0.427 | 0.514 |
Without | 138 | 55 | ||
Perineural invasion | ||||
With | 97 | 44 | 0.208 | 0.648 |
Without | 133 | 54 | ||
Vascular invasion | ||||
With | 78 | 29 | 0.584 | 0.445 |
Without | 152 | 69 | ||
Differentiation degree | ||||
Poorly differentiated | 78 | 37 | 0.446 | 0.504 |
Moderately or well differentiated | 152 | 61 |
Note: BMI, body mass index.