Endobiliary biopsy

Table 1 Tools for endobiliary biopsy sampling

Endoscopic techniques
	Advantage	Disadvantage
ERC + TPB	Safeness, feasibility and large availability; better sensibility for MBS versus brushing	Low sensitivity for MBS (48%), difficulty of cannulation with standard biopsy forceps, not easy targeting of the lesion
ERC + TPB with C-BF	Slight better sensibility (60%) for MBS respect to conventional biopsy forceps	Sampling benefits limited to lesions located to the right intrahepatic bile duct (75%)
Cholangioscopy + endobiliary biopsy	Gain in accuracy for diagnosis of malignancy in indeterminate lesions (85-92%) versus ERCP + TPB	Same safety; issue with direct cholangioscopy related to rare adv events (leakege of air in to portal vein)
IDUS + TPB	Higher sensitivity for malignancy in indeterminate intraductal lesiones (87-91%) versus ERCP + TPB	Advanced experience in both ERCP/EUS requested, lack of standardized procedure and specific devices, time-consuming technique
Interventional radiology techniques
	Advantage	Disadvantage
PTE endobiliary brushing	Safe, cheap and large availability;	Low sensitivity for MBS
PTE endobiliary biopsy	High sensitivity; Larger biopsy cup comapred to ERC + TPB	Indirect visualization of the lesion
Colangioscopy + PTEFB	Direct visualization of the lesion;	Combined procedure with endoscopist; Expensive procedure; small size specimen

TPB: Trans papillary biopsy; IDUS: Intraductal ultrasound; ERC: Endoscopic retrograde cholangiography; PTEFB: Percutaneous transhepatic endobiliary brushing and/or forceps biopsy; C-BF: Controllable biopsy-forceps; EUS: Endoscopic ultrasonography.