Table 1 Characteristics of development and test cohorts
|  | Development cohort (n = 150) | Test cohort (n = 40) | P-value |
|---|---|---|---|
Outcome | |||
Recurrence within 1 year | 55 (36.7) | 17 (42.5) | 0.62 |
Pre-operative clinical features | |||
Age, years (mean ± SD) | 66.3 ± 9.3 | 69.3 ± 8.9 | 0.06 |
Sex | Â | Â | 0.68 |
 Male | 69 (46.0) | 18 (45.0) |  |
 Female | 81 (54.0) | 22 (55.0) |  |
CA19-9 (mean ± SD) | 551.0 ± 1,291.6 | 176.6 ± 320.4 | 0.07 |
CT radiologic features | |||
Tumor location |  |  | < 0.01 |
 Head/neck | 52 (34.7) | 24 (60.0) |  |
 Body/tail | 98 (65.3) | 16 (40.0) |  |
Abutment to the PV and/or SMV | 27 (18.0) | 6 (15.0) | 0.83 |
Peripancreatic infiltration | 72 (48.0) | 19 (47.5) | > 0.99 |
Adjacent organ invasion | 27 (18.0) | 5 (12.5) | 0.56 |
Enlarged lymph node | 18 (12.0) | 6 (15.0) | 0.81 |
Obstructive pancreatitis | 48 (32.0) | 10 (25.0) | 0.51 |
Upstream parenchymal atrophy | 42 (28.0) | 11 (27.5) | > 0.99 |
Main pancreatic duct dilatation | 104 (69.3) | 26 (65.0) | 0.74 |
Post-operative features | |||
Tumor size, cm | 2.6 ± 0.8 | 2.8 ± 0.7 | 0.048 |
Tumor differentiation | Â | Â | 0.76 |
 G1 | 7 (4.7) | 2 (5.0) |  |
 G2 | 117 (78.0) | 33 (82.5) |  |
 G3 | 26 (17.3) | 5 (12.5) |  |
T stage | Â | Â | 0.86 |
 Tis | 1 (0.7) | 0 (0.0) |  |
 T1 | 31 (20.7) | 7 (17.5) |  |
 T2 | 118 (78.7) | 33 (82.5) |  |
N stage | Â | Â | 0.93 |
 N0 | 73 (48.7) | 21 (52.5) |  |
 N1 | 65 (43.3) | 16 (40.0) |  |
 N2 | 12 (8.0) | 3 (7.5) |  |
Resection margin | Â | Â | 0.39 |
 R0 | 120 (80.0) | 35 (87.5) |  |
 R1 | 30 (20.0) | 5 (12.5) |  |
Adjuvant chemotherapy/CCRT | 106 (70.7) | 35 (87.5) | 0.050 |