Endoscopic sphincterotomy (ES) provides no benefit to patients receiving self-expandable metallic stents (SEMS) for a biliary stricture caused by pancreatic cancer, researchers report in the June issue of Clinical Gastroenterology and Hepatology. The randomized controlled trial showed that ES procedure did not affect number of adverse events, SEMS patency, or patient survival.
SEMS are often placed, via endoscopic retrograde cholangiopancreatography, to provide palliative care to patients with biliary decompression due to malignancies. Many endoscopists perform ES before SEMS placement, because separating the biliary and pancreatic orifices might prevent post-procedural pancreatitis. However, it is not clear whether ES actually prevents pancreatitis or has any effect on other adverse events.
Tsuyoshi Hayashi et al conducted a multi-center study to investigate the effects of ES on the incidence of adverse events associated with SEMS placement for biliary strictures in almost 200 patients with unresectable pancreatic cancer.
The patients were assigned randomly to groups that did or did not receive ES before SEMS placement at 25 hospitals in Japan. The authors measured the frequency of adverse events within 30 days specifically related to ES (pancreatitis, bleeding, or perforation), and followed the patients for a mean 192 days.
Hayashi et al found similar rates of early adverse events between the group that did not receive ES (9/98, 9.2%) and the group that did (10/96, 10.4%). Post-procedural pancreatitis developed in 8 patients in the non-ES group and 9 patients in the ES group.
Median time to stent dysfunction and median patient survival times did not differ significantly between the groups (see figure).
The authors conclude that ES is not required before placement of SEMS for biliary obstruction caused by unresectable pancreatic cancer.
In an editorial that accompanies the article, Dennis Yang and Peter V. Draganov explain that many other factors apart from ES before SEMS placement (etiology of the obstruction, pancreatic function, uncovered vs covered SEMS), are likely to affect outcomes and account for some of the conflicting findings on this topic.
However, prospective studies of these variables and their effect on post-endoscopic pancreatitis are a challenge, because of the limited number of subjects required and the low rate of this complication.
Yang and Draganov add that ES before SEMS placement might protect against complications in patients with other causes of malignant or benign biliary obstruction. However, ES cannot be advocated as standard of practice in patients undergoing SEMS placement—especially when the low yet serious associated risks of ES are taken into consideration.