Endoscopic biliary drainage techniques for bilirubin normalization in distal malignant biliary obstruction: A comprehensive review

Table 1 Characteristics of the included studies

Ref.	Study design	Country	Study type	Enrollment period
Kahaleh et al[23]	Retrospective	United States	Monocentric	2001-2003
Weston et al[24]	Retrospective	United States	Monocentric	2002-2005
Weston et al[25]	Retrospective	United States	Monocentric	2006-2007
Cabral et al[26]	Retrospective	Brazil	Monocentric	2015
Pausawasdi et al[27]	Retrospective	Thailand	Monocentric	2007-2017
Mikalsen et al[28]	Retrospective	Norway	Monocentric	2015-2021
Naidu et al[29]	Prospective	India	Monocentric	2023-2024
Martínez-Moreno et al[30]	Retrospective	Spain	Multicentric	2016-2024
Chieng et al[31]	Retrospective	New Zealand	Multicentric	2017-2023

Table 2 Summary of studies reporting on the effectiveness of endoscopic biliary drainage for bilirubin normalization in distal malignant biliary obstruction

Ref.	Number	Cancer type (n)	BD modality	Stent type (n)	Intention	Bilirubin normalization (%)	Bilirubin normalization definition	Time to bilirubin normalization
Kahaleh et al[23]	80	Pancreas (62). Cholangiocarcinoma (6). Ampullary (3). Metastasis (9)	ERCP	Covered SEMS 10 mm (80)	First-line	73	TB ≤ 1.2 mg/dL at 30 days
Weston et al[24]	156	Pancreas (63). Cholangiocarcinoma (16). Gallbladder (7). Metastasis (45). Other (25)	ERCP	PS 7/8.5/10 Fr (75). SEMS 6/8/10 mm (81)	First-line	73.2	TB ≤ 2 mg/dL within 6 weeks	Pre-stent TB < 5 mg/dL: 2.6 weeks. Pre-stent TB 5-10 mg/dL: 2.7 weeks. Pre-stent TB > 10 mg/dL: 5.6 weeks
Weston et al[25]	177	Pancreas (125). Cholangiocarcinoma (16). Ampullary (8). Metastasis (18). Other (10)	ERCP	Uncovered SEMS 8/10 mm (177)	First-line	Total: 59.9. N-SEMS: 65.4. SS-SEMS: 58.3	TB ≤ 2 mg/dL
Cabral et al[26]	58	Pancreas (44). Neuroendocrine tumor (3). Ampullary (2). Metastasis (9)	ERCP	PS 8.5/10 Fr (23). SEMS 10 mm (35)	First-line	Total: 62.1. SPS: 41.2. MPS: 83.3. SEMS: 68.6	TB < 2 mg/dL	SPS: 16.6 days. MPS: 38.4 days. SEMS: 19.5 days
Pausawasdi et al[27]	511: DC: 383; VC: 128 (295 DMBO)	Intrahepatic cholangiocarcinoma (43). Hilar cholangiocarcinoma (138). Extrahepatic cholangiocarcinoma (60). Pancreas (160). Gallbladder (45). Ampullary (19)	ERCP	PS (173). Uncovered SEMS (293). Covered SEMS (9). Partially-covered SEMS (4). Two SEMS (19). Two PS (10). One SEMS and one PS (3)	First-line	DC: 31.2. VC: 26.9	TB ≤ 1.2 mg/dL within 6 weeks
Mikalsen et al[28]	596 (436 DMBO)	Pancreas (308). Cholangiocarcinoma (95). Ampullary (21). Gallbladder (12). Metastasis (117). Other (43)	ERCP	PS (198). Covered SEMS (272). SEMS + PS (4). None (122)	First-line	60.2 (284/472)	TB < 4.68 mg/dL within 30 days
Naidu et al[29]	101 (33 DMBO)		ERCP	PS (94). SEMS (7)	First-line	Within 7 days: 21.3. Within 15 days: 60.6. Within 30 days: 78.7	TB < 3 mg/dL within 7 days, 15 days, and 30 days
Martínez-Moreno et al[30]	96		EUS-GBD	EC-LAMS 6/8/10/15 mm ± coaxial PS	After ERCP and/or EUS-BD failure	65.6	TB < 3 mg/dL	15 (7-27)
Chieng et al[31]	26	Pancreas (20). Cholangiocarcinoma (2). Ampullary (1). Other (3)	EUS-GBD	EC-LAMS 8/10/15 mm ± coaxial PS	After ERCP and/or EUS-BD failure	19.2	Full bilirubin normalization over the follow-up

BD: Biliary drainage; DC: Derivation cohort; DMBO: Distal malignant biliary obstruction; EC-LAMS: Electrocautery-enhanced lumen apposing metal stent; ERCP: Endoscopic retrograde cholangiopancreatography; EUS-BD: Endoscopic ultrasound-guided biliary drainage; EUS-GBD: Endoscopic ultrasound-guided gallbladder drainage; MPS: Multiple plastic stents; N-SEMS: Nitinol self-expandable metal stent; PS: Plastic stent; SEMS: Self-expandable metal stent; SPS: Single plastic stent; SS-SEMS: Stainless steel self-expandable metal stent; TB: Total bilirubin; VC: Validation cohort.