Risk prediction platform for pancreatic fistula after pancreatoduodenectomy using artificial intelligence

Table 1 Clinicopathologic variables included in the machine learning algorithms

Variables	Values	Variables	Values
Age (yr)	67.7 ± 10.1	Preoperative ERBD/ENBD (n, %)	470 (26.6)
Sex (male/female)	1079: 690	Preoperative PTBD (n, %)	254 (14.4)
Body mass index (kg/m2)	22.5 ± 3.8	Preoperative ERPD (n, %)	19 (1.1)
Heart disease including hypertension (n, %)	735 (41.5)	Neoadjuvant therapy (RT/chemotherapy/CCRT/No)	2: 6: 16: 1745
Diabetes mellitus (n, %)	472 (26.7)	Operative time (min)	443.2 ± 90.1
Pulmonary disease (n, %)	153 (8.6)	†Intraoperative fluid infusion (mL)	3129 ± 3495
Liver disease (n, %)	99 (5.6)	Intraoperative transfusion (n, %)	171 (9.7)
Cerebrovascular disease (n, %)	73 (4.1)	Estimated blood loss (ml)	962.4 ± 665.1
Chronic kidney disease (n, %)	17 (1.0)	Soft pancreas (n, %)	750 (43.2)
ASA score (1-4)	372:1267: 128: 2	Pancreatic duct diameter (mm)	4.2 ± 2.8
White blood cell count (x10³/μL)	6.6 ± 2.3	Type of surgery (PPPD/PRPD/PD)	1254: 244: 271
Hemoglobin (g/dL)	10.9 ± 1.5	Combined organ resection (n, %)	67 (3.8)
Platelet count (x10³/μL)	280.2 ± 52.7	Combined vascular resection(n, %)	188 (10.6)
Albumin (d/dL)	3.5 ± 0.4	C- reactive protein (mg/dL)	1.9 ± 10.9
Total bilirubin level (mg/dL)	3.5 ± 4.3	CA 19-9 (U/mL)	1786.5 ± 7141.5
Combined portal vein resection (n, %)	175 (9.9)	P-duct stent (Internal/external/none)	1051: 134: 584
Amylase (U/L)	94.5 ± 5586.9	Co-existing pancreatitis (n, %)	370 (20.9)
Lipase (U/L)	160.5 ± 277.0	‡Location of tumor (Pancreas/others)	856: 913
Anastomotic methods (1) (Duct-to-mucosa/Dunkin)	1756: 13	Anastomotic methods (2) (P-J/P-G/Others)	1761: 8: 0

Total fluid infusion consisted of total amount of intravenous crystalloid, colloid, transfusion. 377 ampulla of Vater cancers, 446 bile duct cancers, 90 duodenal cancers. Pancreatic cystic tumors and neuroendocrine tumors belonged to pancreas. RBD: Endoscopic retrograde biliary drainage; ENBD: Endoscopic nasogastric biliary drainage; PTBD: Percutaneous transhepatic biliary drainage; ERPD: Endoscopic retrograde pancreatic drainage; RT: Radiotherapy; CCRT: Concomitant chemo- and radiotherapy; PP- or PRPD: Pylorus-preserving or pylorus-resecting pancreaticoduodenectomy; CA: Carbohydrate antigen; P-J: Pancreaticojejunostomy; P-G: Pancreaticogastrostomy.