Table 1.
Patient, tumour, and treatment characteristics of 1071 patients after resection for pancreatic cancer
| Variable | All patients, n = 1071 | Missing | After imputation, n = 1071 |
|---|---|---|---|
| Sex ratio (M:F) | 578:493 | – | 578:493 |
| Age (years), mean(s.d.) | 67(9) | – | 67(9) |
| BMI (kg/m2) | – | 9 (1) | – |
| <25 | 597 (56) | 602 (56) | |
| ≥25 | 465 (43) | 469 (44) | |
| Charlson co-morbidity index | – | 67 (6) | – |
| <2 | 626 (58) | 668 (62) | |
| ≥2 | 378 (35) | 403 (38) | |
| ASA classification | – | 16 (1) | – |
| I–II | 796 (74) | 807 (75) | |
| III–IV | 259 (24) | 264 (25) | |
| ECOG performance score at primary diagnosis | – | 322 (30) | – |
| 0–1 | 663 (62) | 942 (88) | |
| 2–4 | 86 (8) | 129 (12) | |
| Preoperative serum CA 19-9 in U/mL, median (i.q.r.) | 150 (36–500) | 342 (32) | 151 (36–502) |
| Preoperative bilirubin (µmol/l), median (i.q.r.) | 32 (10–111) | 449 (42) | 31 (10–111) |
| Method of surgery* | – | 16 (1) | – |
| Open | 901 (84) | 913 (85) | |
| Laparoscopic | 106 (10) | 108 (10) | |
| Robot | 48 (4) | 50 (5) | |
| Type of resection | – | 26 (2) | – |
| Pancreatoduodenectomy | 854 (80) | 875 (82) | |
| Body/tail resection | 147 (14) | 152 (14) | |
| Total pancreatectomy | 36 (3) | 36 (3) | |
| Other | 8 (1) | 8 (1) | |
| Location of tumour | – | 51 (5) | – |
| Head | 862 (80) | 907 (85) | |
| Body/tail | 158 (15) | 164 (15) | |
| Vascular resection | 275 (26) | 3 (0) | 275 (26) |
| Microscopic perineural invasion | 795 (74) | 179 (17) | 945 (88) |
| Microscopic lymphovascular invasion | 554 (52) | 266 (25) | 716 (67) |
| Tumour size (mm), median (i.q.r.)† | 30 (25–40) | 16 (1) | 30 (25–40) |
| Tumour differentiation | – | 124 (12) | – |
| Well/moderate | 657 (61) | 742 (69) | |
| Poor | 290 (27) | 329 (31) | |
| Total number of resected lymph nodes, median (i.q.r.) | 15 (10–20) | 14 (1) | 15 (10–20) |
| No. of positive lymph nodes, median (i.q.r.) | 2 (0–5) | 6 (1) | 2 (0–5) |
| TNM stage 8th AJCC edition | – | 89 (8) | – |
| ≤Stage 2a | 262 (24) | 295 (28) | |
| ≥Stage 2b | 720 (67) | 776 (72) | |
| Resection margin status (mm) | – | 26 (2) | – |
| R0 >1.0 | 503 (47) | 519 (48) | |
| R1 ≤1.0 | 542 (51) | 552 (52) | |
| Major complications‡ | 306 (29) | 2 (0) | – |
| Length of hospital stay (days), median (i.q.r.) | 11 (8–16) | 3 (0) | – |
| Adjuvant chemotherapy | 663 (62) | 45 (4) | – |
| Type of adjuvant chemotherapy§ | – | 38 (6) | – |
| Gemcitabine monotherapy | 546 (82) | ||
| FOLFIRINOX | 8 (1) | ||
| Gemcitabine combination therapy | 62 (9) | ||
| Other | 9 (1) | ||
| No. of cycles of adjuvant chemotherapy, median (i.q.r.)§ | 6 (4–6) | 96 (14) | – |
| Greater than or equal to 80% of prescribed cycles completed§ | 400 (60) | 100 (15) | – |
| Overall survival (months), median (95% c.i.) | 20 (19 to 22) | 25 (2) | – |
| Disease-free interval (months), median (95% c.i.) | 15 (14 to 16) | 25 (2) | – |
| Recurrence | 753 (70) | 17 (2) | – |
Values are n (%) unless otherwise indicated. Percentages may not sum to 100 because of rounding. *Converted laparoscopic procedures are included as open procedures. †Maximum diameter of the tumour. ‡Clavien–Dindo classification grade greater than or equal to III; all postoperative complications requiring surgical, endoscopic, or radiological intervention, or causing organ failure or death. §Calculated in a subset of patients who started with adjuvant chemotherapy (663 patients). s.d., standard deviation; ECOG, Eastern Cooperative Oncology Group; CA, carbohydrate antigen; i.q.r., interquartile range; AJCC, American Joint Committee on Cancer; FOLFIRINOX, 5-fluorouracil/leucovorin/irinotecan/oxaliplatin chemotherapy.