Machine learning model-based prediction of postpancreatectomy acute pancreatitis following pancreaticoduodenectomy: A retrospective cohort study

Table 1 Clinical baseline data and surgical information, n (%)

Variables	Total (n = 381)
Age, median (IQR), years	65 (57, 70)
Sex: Female	138 (36.2)
BMI, mean ± SD, kg/m2	22.8 ± 3.3
Diabetes mellitus	91 (23.9)
Hypertension	105 (27.6)
CAD	28 (7.4)
Alcohol consumption	66 (17.3)
Smoking	74 (19.4)
Jaundice	241 (63.3)
COPD	13 (3.4)
ASA
I/II	243 (63.8)
III/IV	138 (36.2)
Pathology: PDAC/CP	154 (40.4)
MPDD, median (IQR), mm	2.9 (1.7, 4.7)
Surgical modality
PD	229 (60.1)
PPPD	152 (39.9)
Venous resection	83 (21.8)
Pancreatic texture
Firm	194 (50.9)
Soft	187 (49.1)
Pancreatic duct stent
No	6 (1.6)
Internal stent	344 (90.3)
External stent	31 (8.1)
surgery time, median (IQR), minute	370 (306, 507)
EBL, median (IQR), mL	300 (200, 400)

IQR: Interquartile range; BMI: Body mass index; CAD: Coronary artery disease; COPD: Chronic obstructive pulmonary disease; ASA: American Society of Anesthesiologists; PDAC: Pancreatic ductal adenocarcinoma; CP: Chronic pancreatitis; MPDD: Main pancreatic duct diameter; PD: Pancreaticoduodenectomy; PPPD: Pylorus-preserving pancreatoduodenectomy; EBL: Estimated blood loss.

Table 2 Comparison of baseline preoperative and intraoperative characteristics in relation to postpancreatectomy acute pancreatitis, n (%)

Variables	Without PPAP (n = 293)	PPAP (n = 88)	P value
Age, median (IQR), years	65(58, 70)	64 (55, 69)	0.37
Sex, male	187 (63.8)	56 (63.6)	1
BMI, mean ± SD, kg/m2	22.7 ± 3.3	23.4 ± 3.2	0.064
Diabetes mellitus	73 (24.9)	18 (20.5)	0.473
Hypertension	84 (28.7)	21 (23.9)	0.454
CAD	23 (7.9)	5 (5.7)	0.652
Alcohol consumption	49 (16.7)	17 (19.3)	0.687
Smoking	53 (18.1)	21 (23.9)	0.295
Jaundice	185 (63.1)	56 (63.6)	1
COPD (%)	11 (3.8)	2 (2.3)	0.736
ASA, III/IV	101 (34.5)	37 (42.1)	0.242
Pathology, PDAC/CP	134 (45.7)	20 (22.7)	< 0.001
MPDD, median (IQR), mm	3.1 (1.9, 5.2)	1.9 (1.3, 3.0)	< 0.001
Surgical modality, PPPD	112 (38.2)	40 (45.5)	0.276
Venous resection	62 (21.2)	21 (23.9)	0.695
Pancreatic texture, soft	124 (42.3)	63 (71.6)	< 0.001
Pancreatic duct stent, external stent	19 (6.5)	12 (13.6)	0.094
Surgery time, median (IQR), minute	360 (305, 508)	393 (314, 491)	0.3
EBL, median (IQR), mL	300 (200, 400)	400 (200, 500)	0.04

PPAP: Postpancreatectomy acute pancreatitis; IQR: Interquartile range; BMI: Body mass index; CAD: Coronary artery disease; COPD: Chronic obstructive pulmonary disease; ASA: American Society of Anesthesiologists; PDAC: Pancreatic ductal adenocarcinoma; CP: Chronic pancreatitis; MPDD: Main pancreatic duct diameter; PPPD: Pylorus-preserving pancreatoduodenectomy; EBL: Estimated blood loss.

Table 3 Comparison of postoperative events in relation to postpancreatectomy acute pancreatitis, n (%)

Variables	Without PPAP (n = 293)	PPAP (n = 88)	P value
DFA on POD 1, median (IQR), U/L	553 (82, 2726)	4135 (1379, 8481)	< 0.001
DFA on POD 3, median (IQR), U/L	145 (42, 791)	2349 (627, 6153)	< 0.001
WBC on POD 1, median (IQR), 109/L	12.4 (10.2, 15.0)	13.6 (10.7, 16.9)	0.058
WBC on POD 3, median (IQR), 109/L	9.4 (7.0, 12.5)	11.2 (8.7, 15.1)	< 0.001
CRP on POD 1, median (IQR), mg/L	62.7 (43.2, 90.7)	76.7 (49.8, 116.1)	0.005
CRP on POD 3, median (IQR), mg/L	101.3 (67.0, 142.3)	153.3 (81.0, 201.1)	< 0.001
Serum AMY on POD 1, median (IQR), U/L	110.5 (53.0, 249.3)	312.0 (189.4, 508.3)	< 0.001
Serum AMY on POD 3, median (IQR), U/L	30.0 (18.2, 59.0)	95.0 (62.6, 149.0)	< 0.001
Drain removal time, median (IQR), days	12 (9, 20)	25 (14, 33)	< 0.001
Postoperative hospital stay, median (IQR), days	15.0 (11, 21)	23.5 (15, 33)	< 0.001
POPF	43 (14.7)	49 (55.7)	< 0.001
Grade C POPF	4 (1.4)	8 (9.1)	0.001
DGE	78 (26.6)	34 (38.6)	0.042
PPH	21(7.2)	18 (20.5)	0.001
Interventional treatment	26 (8.9)	28 (31.8)	< 0.001
Biliary fistula	7 (2.4)	5 (5.7)	0.229
Re-operation	8 (2.7)	11 (12.5)	0.001
Organ failure	1 (0.3)	6 (6.8)	< 0.001
90-day mortality	7 (2.4)	7 (8.0)	0.035
30-day readmission	9 (3.1)	6 (6.8)	0.203

PPAP: Postpancreatectomy acute pancreatitis; DFA: Drain fluid amylase; POD: Postoperative day; IQR: Interquartile range; WBC: White blood cell count; CRP: C-reactive protein; AMY: Amylase; POPF: Postoperative pancreatic fistula; DGE: Delayed gastric emptying; PPH: Postpancreatectomy hemorrhage.

Table 4 Performance of different models for predicting postpancreatectomy acute pancreatitis

Model	Training AUC	Testing AUC	Specificity	Sensitivity	MCC	Kappa	NPV	PPV
LR	0.605	0.69	0.524	0.857	0.295	0.214	0.943	0.286
RF	0.824	0.815	0.508	1	0.398	0.273	1	0.311
GBDT	0.875	0.735	0.81	0.643	0.392	0.379	0.911	0.429
XGBoost	0.871	0.706	0.762	0.714	0.392	0.365	0.923	0.4
LGBM	0.87	0.73	0.746	0.714	0.375	0.345	0.922	0.385
CatBoost	0.859	0.822	0.667	0.857	0.408	0.343	0.955	0.364

AUC: Area under the receiver operating characteristic curve; MCC: Matthews correlation coefficient; NPV: Negative predictive value; PPV: Positive predictive value; LR: Logistic regression; RF: Random forest; GBDT: Gradient boosting decision tree; XGBoost: Extreme gradient boosting; LGBM: Light gradient boosting machine; CatBoost: Category boosting.

Table 5 Performance of category boosting model for predicting postpancreatectomy acute pancreatitis based on selected variables

Model	CatBoost
Training AUC	0.837
Testing AUC	0.812
Specificity	0.873
Sensitivity	0.714
MCC	0.535
Kappa	0.529
NPV	0.932
PPV	0.556

CatBoost: Category boosting; AUC: Area under the receiver operating characteristic curve; MCC: Matthews correlation coefficient; NPV: Negative predictive value; PPV: Positive predictive value.