Table 2.
Univariate and multivariate analysis of variables associated with surgical resection (logistic regression) and overall survival (Cox regression) in patients fit to receive chemotherapy using baseline factors for all patients
| Baseline variable | Number | Resection | Survival | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Univariate | Multivariate | Univariate | Multivariate | ||||||
| Odds ratio | P | Odds ratio | P | Hazard ratio | P | Hazard ratio | P | ||
| Sex | |||||||||
| Female | 90 | 1 (Ref) | NA | 1 (Ref) | NA | ||||
| Male | 98 | 1.40 (0.75,2.61) | 0.297 | 0.80 (0.58,1.10) | 0.163 | ||||
| Age (years) | |||||||||
| ≤75 | 148 | 1 (Ref) | NA | 1 (Ref) | NA | ||||
| >75 | 40 | 0.60 (0.27,1.37) | 0.228 | 1.37 (0.94,2.00) | 0.102 | ||||
| Performance status (ECOG) | |||||||||
| 0 | 110 | 1 (Ref) | NA | 1 (Ref) | NA | 1 (Ref) | NA | ||
| 1 | 64 | 1.02 (0.52,1.98) | 0.963 | 0.96 (0.68,1.35) | 0.807 | 0.86 (0.58,1.27) | 0.436 | ||
| >1 | 14 | 0.61 (0.16,2.33) | 0.469 | 2.02 (1.15,3.57) | 0.015 | 1.81 (0.91,3.61) | 0.091 | ||
| BMI (kg/m2)* | |||||||||
| 18.5–30 | 150 | 1 (Ref) | NA | 1 (Ref) | NA | ||||
| <18.5 | 17 | 0.94 (0.31,2.83) | 0.915 | 0.97 (0.55,1.72) | 0.914 | ||||
| ≥30 | 18 | 1.13 (0.40,3.20) | 0.817 | 0.78 (0.45,1.36) | 0.390 | ||||
| Charlson co-morbidity index | |||||||||
| 0 | 95 | 1 (Ref) | NA | 1 (Ref) | NA | ||||
| 1 | 61 | 1.03 (0.51,2.06) | 0.935 | 0.86 (0.60,1.22) | 0.388 | ||||
| >1 | 32 | 0.89 (0.37,2.16) | 0.798 | 1.06 (0.68,1.67) | 0.793 | ||||
| Tumour size (mm) | |||||||||
| 0–20 | 15 | 1 (Ref) | NA | 1 (Ref) | NA | ||||
| 21–40 | 115 | 1.77 (0.53,5.89) | 0.354 | 0.67 (0.37,1.19) | 0.170 | ||||
| >40 | 58 | 0.44 (0.11,1.73) | 0.239 | 0.76 (0.41,1.40) | 0.374 | ||||
| Tumour location | |||||||||
| Caput | 153 | 1 (Ref) | NA | 1 (Ref) | NA | ||||
| Corpus/cauda | 35 | 0.52 (0.21,1.26) | 0.146 | 1.07 (0.72,1.61) | 0.732 | ||||
| Anatomic tumour classification | |||||||||
| Borderline resectable | 96 | 1 (Ref) | NA | 1 (Ref) | NA | 1 (Ref) | NA | ||
| Locally advanced | 92 | 0.17 (0.08,0.35) | <0.001 | 0.20 (0.09,0.46) | <0.001 | 1.22 (0.89,1.67) | 0.224 | ||
| CA19-9 (kU/l)† | |||||||||
| 5–500 | 96 | 1 (Ref) | NA | 1 (Ref) | NA | 1 (Ref) | NA | 1 (Ref) | NA |
| >500 | 67 | 0.44 (0.21,0.92) | 0.028 | 0.44 (0.19,0.98) | 0.045 | 1.83 (1.28,2.60) | <0.001 | 1.65 (1.12,2.41) | 0.010 |
| Primary chemotherapy regimen‡ | |||||||||
| FOLFIRINOX | 103 | 1 (Ref) | NA | 1 (Ref) | NA | 1 (Ref) | NA | 1 (Ref) | NA |
| Gemcitabine/nab-paclitaxel | 48 | 0.66 (0.31,1.41) | 0.284 | 0.68 (0.28,1.62) | 0.379 | 1.50 (1.03,2.18) | 0.034 | 1.43 (0.95,2.16) | 0.084 |
| Gemcitabine | 27 | 0.31 (0.10,0.97) | 0.043 | 0.09 (0.01,0.71) | 0.023 | 1.71 (1.08,2.68) | 0.021 | 1.78 (1.02,3.11) | 0.042 |
Values in parentheses are 95% confidence intervals. ‡Eight patients received other chemotherapy regimens, and two patients underwent upfront surgery followed by adjuvant chemotherapy. CA19-9, carbohydrate antigen 19-9; ECOG, Eastern Cooperative Oncology Group; FOLFIRINOX, 5-fluorouracil with leucovorin, irinotecan and oxaliplatin; NA, not applicable. *BMI, missing data n = 3; †CA19-9 at baseline, missing data n = 11, hyperbilirubinaemia n = 2, non-secretor n = 12.