Table 3.
Prognostic Factors for Survival Identified by Univariate and Multivariate Analyses
| Characteristic | Univariate analysis | Multivariate analysis | ||
|---|---|---|---|---|
| HR (95% CI) | p-value | HR (95% CI) | p-value | |
| Age, yr | ||||
| <65 | Reference | Reference | ||
| ≥65 | 1.643 (1.127–2.396) | 0.010 | 1.476 (1.004–2.170) | 0.048 |
| Sex | ||||
| Male | Reference | |||
| Female | 0.741 (0.507–1.081) | 0.120 | ||
| Tumor location | ||||
| Head | Reference | |||
| Body/tail/others | 1.073 (0.727–1.584) | 0.721 | ||
| Median tumor size, cm | ||||
| ≤3 | Reference | Reference | ||
| >3 | 1.758 (1.217–2.539) | 0.003 | 1.723 (1.171–2.535) | 0.006 |
| Lymph node involvement | ||||
| Absent | Reference | Reference | ||
| Present | 2.160 (1.438–3.245) | <0.001 | 1.716 (1.093–2.692) | 0.014 |
| Angiolymphatic invasion | ||||
| Absent | Reference | Reference | ||
| Present | 1.747 (1.198–2.548) | 0.004 | 1.208 (0.792–1.841) | 0.380 |
| Venous invasion | ||||
| Absent | Reference | Reference | ||
| Present | 1.858 (1.287–2.684) | 0.001 | 1.755 (1.196–2.574) | 0.004 |
| Perineural invasion | ||||
| Absent | Reference | |||
| Present | 1.811 (0.993–3.302) | 0.052 | ||
| Resection margin | ||||
| R0 | Reference | |||
| R1 | 1.484 (0.962–2.290) | 0.074 | ||
| Median preoperative CA19-9, U/mL | ||||
| <128 | Reference | |||
| ≥128 | 1.253 (0.864–1.818) | 0.233 | ||
| Adequate adjuvant therapy | ||||
| Yes | Reference | Reference | ||
| No | 2.207 (1.477–3.297) | <0.001 | 2.064 (1.371–3.109) | 0.001 |
| Tumor cellularity, % | ||||
| <30 | Reference | Reference | ||
| ≥30 | 1.674 (1.159–2.418) | 0.006 | 2.008 (1.361–2.962) | <0.001 |
HR, hazard ratio; CI, confidence interval; R0, no residual tumor; R1, microscopic residual tumor (corresponds to positive resection margins); CA19–9, carbohydrate antigen 19–9.