Table 1.
Patient characteristics and endoscopic interventions in the derivation and validation cohorts.
| Characteristics | Derivation cohort (N = 339) | Validation cohort (N = 112) | P value |
|---|---|---|---|
| Male gender, n (%) | 173 (51.0%) | 64 (57.1%) | 0.262 |
| Age (years) | 64.2 ± 12.4 | 63.4 ± 12.5 | 0.572 |
| Body mass index (kg/m2) | 21.6 ± 3.8 | 22.5 ± 4.7 | 0.037 |
| Waiting time for ERCP (days) | 19.0 (9.0–31.0) | 20.5 (9.5–38.0) | 0.119 |
| Type of malignancy | |||
| Cholangiocarcinoma, n (%) | 181 (53.4%) | 61 (54.5%) | 0.844 |
| Intrahepatic cholangiocarcinoma | 31 (17.1%) | 12 (19.7%) | 0.624 |
| Hilar cholangiocarcinoma | 107 (59.1%) | 37 (60.7%) | 0.645 |
| Extrahepatic cholangiocarcinoma | 43 (23.8%) | 12 (19.7%) | 0.714 |
| Pancreatic cancer | 120 (35.4%) | 39 (34.8%) | 0.912 |
| Gallbladder cancer | 34 (10.0%) | 11 (9.8%) | 0.949 |
| Malignant IPMN | 4 (1.2%) | 1 (0.9%) | 1.000 |
| ECOG performance-status score, n (%) | |||
| 1 | 58 (17.1%) | 16 (14.3%) | 0.484 |
| 2 | 192 (56.6%) | 71 (63.4%) | 0.209 |
| 3 | 89 (26.3%) | 25 (22.3%) | 0.406 |
| Clinical presentation, n (%) | |||
| Abdominal pain | 194 (57.2%) | 62 (55.4%) | 0.729 |
| Jaundice | 303 (89.4%) | 96 (85.7%) | 0.292 |
| Fever | 24 (7.1%) | 6 (5.4%) | 0.526 |
| Weight loss | 216 (63.7%) | 66 (58.9%) | 0.364 |
| Ascending cholangitis | 61 (18.0%) | 21 (18.8%) | 0.857 |
| Pre-endoscopic laboratory | |||
| Hemoglobin (g/dL) | 10.6 ± 3.0 | 10.8 ± 1.5 | 0.428 |
| Platelet (109/L) | 319 (265–399) | 323 (248–412) | 0.724 |
| INR | 1.4 ± 0.7 | 1.4 ± 0.6 | 0.938 |
| Total bilirubin (mg/dl) | 19.2 ± 9.5 | 19.1 ± 10.0 | 0.973 |
| Albumin (g/dL) | 3.2 ± 0.6 | 3.2 ± 0.6 | 0.765 |
| Alkaline phosphatase (IU/L) | 465 (287–680) | 427 (288–698) | 0.783 |
| Creatinine (mg/dl) | 0.8 (0.6–1.0) | 0.8 (0.6–1.0) | 0.546 |
| Cross-sectional imaging | |||
| Size of obstructive tumor (cm) | 3.8 (2.6–5.1) | 3.6 (2.6–5.5) | 0.896 |
| Hilar obstruction, n (%) | 133 (39.2%) | 45 (40.2%) | 0.859 |
| Non-hilar obstruction, n (%) | 206 (60.8%) | 67 (59.8%) | 0.859 |
| Intrahepatic obstruction | 14 (4.1%) | 7 (6.3%) | 0.356 |
| Extrahepatic obstruction | 192 (56.6%) | 60 (53.6%) | 0.571 |
| Combined obstruction, n (%) | 14 (4.1%) | 6 (5.4%) | 0.599 |
| Vascular involvement, n (%) | 161 (47.5%) | 59 (52.7%) | 0.341 |
| Portal vein invasion, n (%) | 96 (28.3%) | 45 (40.2%) | 0.019 |
| Duodenal invasion, n (%) | 31 (9.1%) | 11 (9.8%) | 0.831 |
| Liver metastasis, n (%) | 116 (34.2%) | 34 (30.4%) | 0.452 |
| Distant metastasis, n (%) | 205 (60.5%) | 67 (59.8%) | 0.903 |
| Peritoneal carcinomatosis, n (%) | 41 (12.1%) | 12 (10.7%) | 0.694 |
| Lymph node metastasis, n (%) | 231 (68.0%) | 80 (71.4%) | 0.514 |
| Endoscopic intervention, n (%) | |||
| Presence of metallic/plastic stent | 219 (64.6%)/120 (35.4%) | 76 (67.9%)/36 (32.1%) | 0.530 |
| One stent placement | 317 (93.5%) | 106 (94.6%) | 0.667 |
| One plastic stent placement | 112 (33.0%) | 34 (30.4%) | 0.599 |
| One metallic stent placement | 205 (60.5%) | 72 (64.3%) | 0.472 |
| - Uncovered SEMs | 199 (58.7%) | 67 (59.8%) | 0.835 |
| - Fully covered SEMs | 4 (1.2%) | 4 (3.6%) | 0.110 |
| - Partially covered SEMs | 2 (0.6%) | 1 (0.9%) | 0.576 |
| Two-stent placements | 22 (6.5%) | 6 (5.4%) | 0.667 |
| Two metallic stents | 12 (3.5%) | 4 (3.6%) | 1.000 |
| Two plastic stents | 7 (2.1%) | 2 (1.8%) | 1.000 |
| One metallic and one plastic stent | 3 (13.6%) | 0 | 1.000 |
| Post-endoscopic outcomes | |||
| Post-ERCP complications, n (%) | 34 (10.0%) | 13 (11.6%) | 0.636 |
| Stent dysfunction, n (%) | 92 (27.1%) | 26 (23.2%) | 0.413 |
| Stent patency time (days) | 63 (28.0–105.0) | 81 (40.0–159.0) | 1.000 |
| Bilirubin improvement after stenting†, n (%) | 240 (70.8%) | 81 (72.3) | 0.757 |
| Chemotherapy after ERCP, n (%) | 49 (14.5%) | 16 (14.3%) | 0.965 |
Data are presented as the mean ± standard deviation, median (interquartile range), or number (proportion) of patients with a condition.
IPMN, intraductal papillary mucinous neoplasm; ECOG, Eastern cooperative oncology group; ERCP, endoscopic retrograde cholangiopancreatography; INR, international normalized ratio; SEMs, self-expandable metallic stent.
†Defined by total bilirubin improvement of more than 50% from baseline within 2 weeks after ERCP-guided endobiliary stent placement.