Self-expanding metal stents (SEMSs) provide good palliation of jaundice and symptoms related to malignant biliary obstruction (MBO). Pancreatic ductal adenocarcinoma (PDAC) is increasingly being treated with neoadjuvant therapy prior to definitive consideration of surgical extirpation.
This industry-sponsored, multicenter, noninferiority trial randomized 119 patients with MBO to uncovered SEMS (UCSEMS; 60 patients) versus fully covered SEMS (FCSEMS; 59 patients) before or during neoadjuvant therapy and prior to planned surgery. Sustained biliary drainage, defined as absence of reinterventions for biliary obstructive symptoms before surgery or until 1 year of follow-up, was equivalent between groups (72.9%, UCSEMS vs 72.2%, FCSEMS; p=0.01 for noninferiority). However, the failure modes were significantly different, with migration occurring only with FCSEMSs (6.8%, p=0.03) and ingrowth occurring only with UCSEMSs (16.7%, p<0.01). Serious adverse events during placement were equivalent (FCSEMS, 23.7% vs UCSEMS, 20.0%; p=0.66). Among patients with the gallbladder still in, the rate of acute cholecystitis was also statistically equivalent (FCSEMS, 9.3% vs UCSEMS, 4.8%; p=0.68). Predictors for reintervention included use of a short, 4-cm stent length and presence of the gallbladder in situ, but did not differ by stent type. Use of the 4-cm stent length was equivalent between stent types but associated with presence of the gallbladder.
The demonstration of noninferiority between FCSEMSs and UCSEMSs suggests that either can be appropriately selected for preoperative palliation in patients undergoing neoadjuvant therapy for PDAC. The differing mechanisms of failure and the association of failure with short stents, which were often chosen for patients with persistent gallbladders, suggest decision trees based on anatomic factors might be useful for stent selection, and stents designed to reduce both migration and ingrowth might be useful when malignancy has been confirmed.
Seo DW, Sherman S, Dua KS, et al. Biliary SEMS during neoadjuvant therapy study group. Covered and uncovered biliary metal stents provide similar relief of biliary obstruction during neoadjuvant therapy in pancreatic cancer: a randomized trial. Gastrointest Endosc
2019 July 2. (Epub ahead of print) (https://doi.org/10.1016/j.gie.2019.06.032