Multicenter study of endoscopic preoperative biliary drainage for malignant distal biliary obstruction

Table 1 Characteristics of 419 patients who underwent endoscopic preoperative biliary drainage via plastic stent and nasobiliary catheter n (%)

	All patients (n = 419)	PS (n = 253)	NBC (n = 166)	P value
Sex, male	269 (64)	163 (64)	106 (64)	0.905
Age (yr)	69 (63-75)	69 (62-75)	70 (63-76)	0.274
Performance status, 0/1/2	331/81/7 (79/19/2)	201/50/2 (79/20/1)	130/31/5 (78/19/3)	0.781
Primary cancer, pancreas/biliary tract/ampullary	194/175/50 (46/42/12)	133/91/29 (53/36/11)	61/84/21 (37/51/13)	0.003
Primary tumor size (mm)	20 (15-30)	20 (14-28)	22 (18-30)	0.008
Length of biliary stricture (mm)	16 (11-22)	15 (11-22)	17 (12-23)	0.154
Diameter of proximal bile duct (mm)	15 (12-18)	15 (12-18)	14 (11-17)	0.050
Involvement of intrapancreatic bile duct	354 (84)	221 (87)	133 (80)	0.048
Tumor invasion into duodenum	213 (51)1	132 (53)	81 (51)	0.823
Cholangitis on admission	64 (15)	34 (13)	30 (18)	0.200
Total bilirubin (mg/dL)	7.8 (3.3-13.2)	7.5 (3.3-12.6)	8.6 (3.4-13.5)	0.536

¹Data were not obtained in nine patients. Data are expressed as numbers (%) or median (interquartile range). PS: Plastic stent; NBC: Nasobiliary catheter.

Table 2 Procedures, adverse events, and causes of dysfunction in patients who underwent preoperative plastic stent and nasobiliary catheter placement n (%)

	All patients (n = 419)	PS (n = 253)	NBC (n = 166)	P value
Procedures of the initial ERCP
EST or EPBD	178 (43)	101 (40)	77 (46)	0.202
Biopsy or brushing of the bile duct	362 (86)	214 (85)	148 (89)	0.234
Positive for cancer	250 (60)	150 (59)	100 (60)
Biliary stents/catheters placed
Diameter 5-6/7-7.5/8.5-10 Fr	98/236/85 (23/56/20)	18/150/85 (7/59/34)	80/86/0 (48/52/0)	< 0.001
Pig-tailed tip/straight tip	152/2241	74/177 (29/71)	78/47 (62/38)	< 0.001
Placement of pancreatic stent	41 (10)	25 (10)	16 (10)	0.935
Adverse events (other than cholangitis)
Pancreatitis	40 (10)	26 (10)	14 (8)	0.612
Mild/moderate/severe	30/10/0
Cholecystitis	4 (1)	2 (1)	2 (1)	0.650
Others	4 (1)	2 (1)	2 (1)	0.650
Stent/catheter dysfunction	118 (36)	88 (35)	30 (18)	< 0.001
Causes of PS/NBC dysfunction
Occlusion or cholangitis	85	69 (27)	16 (10)	0.013
Insufficient drainage	19	14 (6)	5 (3)	0.330
Migration	10	5 (2)	5 (3)	0.526
Inadvertent removal	4	NA	4 (2)	NA
Number of ERCPs	2 (1-2)	1 (1-1)	2 (1-2)	< 0.0001

¹Data was not obtained in 43 patients. A part of data on tips of PS/NBC was missing. “Occlusion or cholangitis” included jaundice or re-elevation of liver enzyme with or without fever-up, and fever-up without other causes even if no elevation of liver enzyme; “Insufficient drainage” included persistent liver dysfunction or limited improvement of the elevated liver enzyme, which is sometimes difficult to distinguish from other causes of liver dysfunction. PS: Plastic stent; NBC: Nasobiliary catheter; ERCP: Endoscopic retrograde cholangiopancreatography; EST: Endoscopic sphincterotomy; EPBD: Endoscopic papillary balloon dilation; NA: Not applicable.

Table 3 Univariate and multivariate competing risks regression analyses to identify risk factors for dysfunction of plastic stent or nasobiliary catheter in 419 patients who underwent endoscopic preoperative biliary drainage

	Univariate analysis		Multivariate analysis
	SHR (95%CI)	P value	SHR (95%CI)	P value
Sex, male	0.96 (0.64-1.44)	0.839
Age > 70 yr	1.06 (0.72-1.56)	0.773
Performance status ≥ 1	0.67 (0.39-1.14)	0.139	0.70 (0.39-1.24)	0.221
Primary cancer
Biliary tract	Reference		Reference
Pancreas	1.61 (1.06-2.44)	0.025	1.30 (0.84-2.03)	0.240
Ampullary	0.89 (0.43-1.84)	0.758	0.81 (0.40-1.65)	0.568
Primary tumor size > 20 mm	0.90 (0.61-1.33)	0.603
Length of biliary stricture > 20 mm	1.04 (0.71-1.53)	0.854
Diameter of proximal bile duct > 15 mm	0.94 (0.64-1.38)	0.755
Tumor invasion into duodenum	1.10 (0.75-1.63)	0.621
Cholangitis on admission	0.77 (0.44-1.37)	0.378
Total bilirubin ≥ 8 mg/dL	1.16 (0.79-1.71)	0.447
Placement of PS	4.76 (2.63-8.33)	< 0.001	4.76 (2.44-10.0)	< 0.001
Diameter of biliary stent/catheter
5-6 Fr	Reference		Reference
7-7.5 Fr	1.92 (1.07-3.43)	0.029	0.95 (0.50-1.83)	0.885
8.5-10 Fr	2.44 (1.28-4.66)	0.007	0.93 (0.44-1.99)	0.850
Pig-tailed tip	1.05 (0.71-1.57)	0.796

PS: Plastic stent; NBC: Nasobiliary catheter; SHR: Subdistribution hazard ratio.

Table 4 Univariate and multivariate competing risk regression analyses to identify risk factors for plastic stent dysfunction in 253 patients who underwent endoscopic preoperative plastic stent placement

	Univariate analysis		Multivariate analysis
	SHR (95%CI)	P value	SHR (95%CI)	P value
Sex, male	1.00 (0.65-1.55)	0.993
Age > 70 yr	1.15 (0.76-1.74)	0.509
Performance status ≥ 1	0.84 (0.49-1.45)	0.534
Primary cancer
Biliary tract	Reference
Pancreas	1.27 (0.81-1.99)	0.303
Ampullary	0.83 (0.39-1.79)	0.637
Primary tumor size > 20 mm	1.10 (0.72-1.69)	0.657
Length of biliary stricture > 20 mm	1.01 (0.66-1.54)	0.957
Diameter of proximal bile duct > 15 mm	0.85 (0.56-1.28)	0.432
Tumor invasion into duodenum	1.10 (0.72-1.67)	0.659
Cholangitis on admission	0.79 (0.41-1.52)	0.479
Total bilirubin ≥ 8 mg/dL	1.32 (0.87-2.00)	0.192	1.43 (0.94-2.18)	0.096
Diameter of biliary stent/catheter
5-6 Fr	Reference
7-7.5 Fr	0.76 (0.37-1.56)	0.446
8.5-10 Fr	0.67 (0.31-1.46)	0.314
Pig-tailed tip	1.73 (1.14-2.63)	0.010	1.72 (1.13-2.64)	0.012

PS: Plastic stent; SHR: Subdistribution hazard ratio.

Table 5 Univariate and multivariate competing risks regression analyses to identify prognostic factors for jaundice resolution after endoscopic preoperative biliary drainage in 325 patients

	Univariate analysis		Multivariate analysis
	SHR (95%CI)	P value	SHR (95%CI)	P value
Sex, male	0.90 (0.71-1.14)	0.387
Age ≥ 69 yr	1.01 (0.80-1.27)	0.932
Performance status ≥ 1	1.00 (0.73-1.39)	0.979
Primary cancer
Biliary tract	Reference
Pancreas	1.07 (0.84-1.36)	0.602
Ampullary	1.19 (0.80-1.77)	0.389
Primary tumor size > 20 mm	0.81 (0.63-1.04)	0.094	0.91 (0.69-1.20)	0.524
Length of biliary stricture > 20 mm	0.80 (0.63-1.01)	0.059	0.82 (0.63-1.06)	0.134
Diameter of proximal bile duct > 15 mm	0.78 (0.62-0.98)	0.033	0.81 (0.63-1.05)	0.107
Tumor invasion to duodenum	0.96 (0.76-1.21)	0.721
Cholangitis on admission	1.11 (0.80-1.54)	0.528
Total bilirubin ≥ 8 mg/dL	0.41 (0.31-0.55)	< 0.001	0.43 (0.32-0.58)	< 0.001
EST or EPBD	1.02 (0.81-1.28)	0.897
Diameter of biliary stent/catheter
5-6 Fr	Reference
7-7.5 Fr	0.96 (0.73-1.25)	0.738
8.5-10 Fr	0.97 (0.70-1.34)	0.859
Pig-tailed tip	1.05 (0.83-1.34)	0.681
Placement of NBC	0.83 (0.66-1.06)	0.129	0.92 (0.71-1.19)	0.520

In these competing risks regression analyses, jaundice resolution was set as the outcome and thus, a higher SHR indicated a higher probability of early resolution of jaundice. SHR: Subdistribution hazard ratio; CI: Confidence interval; EST: Endoscopic sphincterotomy; EPBD: Endoscopic papillary balloon dilation; NBC: Nasobiliary catheter.