Plastic or Metal Stents for Primary or Recurrent Inoperable Malignant Extrahepatic Biliary Obstruction

Malignant extrahepatic biliary obstruction is a frequent complication of
inoperable periampullary cancer and causes significant morbidity due to
jaundice, cholangitis and malabsorption. The primary goal of treatment is to
relieve CBD obstruction, which can be performed by the placement of a plastic
stent or self-expanding metal stent (SEMS) during Endoscopic Retrograde
Cholangio-Pancreaticography (ERCP). Plastic stents are most often used because
of their efficacy and low costs, however stent obstruction occurs frequently.
SEMS, with a larger luminal diameter, are associated with a longer stent
patency, but are more expensive. Another disadvantige is the tumour ingrowth.
More recently, covered SEMS have been introduced to prevent tumor ingrowth. The
disadvantage of covered stents is stent migration, and cholecystitis and
pancreatitis caused by obstruction of the cystic duct and pancreatic duct.
Until now, only a limited number of studies have compared these devices

To define indications for recently developed, but more expensive,
self-expanding metal stents (SEMS) versus cheaper plastic stents in patients
with primary or recurrent inoperable malignant extrahepatic common bile duct
(CBD) obstruction, based on an individualized prognostic risk.

a) RCT in 26 Dutch centers in 2 strata: 1. 300 patients with primary stent
placement for CBD obstruction, and 2. 160 patients with recurrent CBD
obstruction after previous stent placement. b) Retrospective cohort study for
prognostic model development (n>500). The prognostic model will be validated
with the RCT data and provide the basis for a subgroup specific comparison of
stent types according to individualized risk.

After informed consent, 300 (primary) + 160 (recurrent) patients will be
randomized to: a) plastic stent, b) uncovered SEMS, or c) covered SEMS in a
1:1:1 ratio.

During the first 30 days after stent placement, patients will keep a diary on
physical symptoms (such as fever, jaundice, pruritis, etc.), and self-rated
health (EQ-VAS). If he patient is unable to complete a diary (which may be the
case if a complication develops on the first few days after stent placement),
data will be collected by proxy assessment. After the first 30 days, the
patients will provide these data on a weekly basis.
Patients will be followed up by home visits of a member of a team of specially
trained research nurses at 14 days, 1 month and then monthly after
randomization until 6 months. After 6 months patients will be visited every 2
months. During these visits, the diaries will be checked and HRQoL
questionnaires and economic evaluation questionnaires will be completed. In
addition, blood samples will be collected at 14 days for bilirubin levels. If
the condition of patients allows, patients will be referred for a
reintervention to treat recurrent CBD obstruction. Due to the unpredictable
timing of reinterventions, it is not feasible to assess the burden of
intervention for patients and informal care givers in all participating
hospitals, and this will therefore be performed at least in the UMCU, and in
other hospitals on a voluntary basis. Patients will be followed until death or
at least for 1 year.