title: A prospective randomized trial of Tannenbaum-type Teflon-coated stents versus polyethylene stents for distal malignant biliary obstruction.
abstract: OBJECTIVE
  Stent clogging is a major limitation in the palliative treatment of malignant biliary obstruction. Preliminary studies suggested improved duration of patency of a Tannenbaum design stent with a stainless steel mesh and an inner Teflon coating (TTC). We compared the patency of a TTC stent with a conventional polyethylene (PE) stent in a prospective randomized trial.
  
  
  METHODS
  Between February 1998 and September 1998 we included 60 patients with distal malignant bile duct obstruction. Diagnosis included carcinoma of the pancreas (n = 57) and ampullary cancer (n = 3). There were 29 men and 31 women with a median age of 77 years. Stent diameter (10 Fr) and length (11 cm) were similar but both stent design and material were different: a Tannenbaum design stent with a stainless steel mesh and an inner Teflon coating, and an Amsterdam-type PE stent.
  
  
  RESULTS
  Sixty patients were evaluated; 30 in the TTC group and 30 in the PE group. Early complications occurred in two patients in each group. Stent dysfunction occurred in 18 of TTC stents and 12 of PE stents. Median stent patency was 102 days for TTC and 142 days for PE stents (P = 0.41). Median survival did not differ significantly for both treatment groups (TTC, 121 days; PE, 105 days). Stent migration, in all cases proximal into the common bile duct, occurred in four patients in the TTC group versus zero in the PE group (P = 0.038).
  
  
  CONCLUSIONS
  This study did not confirm improved patency of Tannenbaum-type Teflon-coated stents. Proximal migration prompts for additional design modifications.
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands. a.m.vanberkel@amc.uva.nl
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: van Berkel
authors.forename: Inge L
authors.initials: IL
authors.lastname: Huibregtse
authors.forename: Jacques J G H M
authors.initials: JJ
authors.lastname: Bergman
authors.forename: Erik A J
authors.initials: EA
authors.lastname: Rauws
authors.forename: Marco J
authors.initials: MJ
authors.lastname: Bruno
authors.forename: Kees
authors.initials: K
authors.lastname: Huibregtse
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014670:Ampulla of Vater; D001650:Bile Duct Neoplasms / Q000150:complications* / Q000601:surgery; D002760:Cholangiopancreatography, Endoscopic Retrograde; D002779:Cholestasis / Q000209:etiology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000150:complications* / Q000601:surgery; D020959:Polyethylene; D011138:Polytetrafluoroethylene; D011183:Postoperative Complications / Q000209:etiology; D011446:Prospective Studies; D011474:Prosthesis Design; D015607:Stents; D016896:Treatment Outcome
chemical_list: D011138:Polytetrafluoroethylene; D020959:Polyethylene