# Outcomes of 6‐mm diameter fully covered self‐expandable metal stents for preoperative biliary drainage in pancreatic cancer

## TL;DR

The study compares 6-mm and 10-mm metal stents for biliary drainage in pancreatic cancer patients and finds no significant difference in outcomes.

## Contribution

This is the first study to evaluate 6-mm fully covered self-expandable metal stents for preoperative biliary drainage in borderline resectable pancreatic cancer.

## Key findings

- Stent-related non-event rates were similar between 6-mm and 10-mm stents.
- 6-mm stents did not increase the risk of recurrent biliary obstruction or stent migration.
- Tumor involvement of the pancreatic duct reduced the risk of pancreatitis.

## Abstract

10‐mm self‐expandable metal stents (SEMSs) are commonly used for preoperative biliary drainage in pancreatic cancer. However, smaller diameter SEMSs have attracted attention with the attempt to reduce stent‐related adverse events (AEs).

We retrospectively analyzed consecutive borderline resectable pancreatic cancer patients who underwent neoadjuvant therapy and fully covered SEMS (FCSEMS) placement from April 2015 to May 2023. The primary outcome was stent‐related non‐event rate (NER), which was defined as the rate of completion of surgery without developing any preoperative events (recurrent biliary obstruction [RBO] or stent‐related AEs). Secondary outcomes included stent‐related AEs, causes of RBO, and cumulative incidence of RBO. Risk factors for pancreatitis, RBO, and stent migration were also examined.

A total of 76 patients were included (6‐mm group: 23; 10‐mm group: 53). Stent‐related NER (57% vs. 64%, p = 0.610), stent‐related AEs (4% vs. 15%, p = 0.263), overall RBO rates (39% vs. 23%, p = 0.168), cumulative incidence of RBO (hazard ratio, 2.24; 95% confidence interval, 0.95–5.25; p = 0.065) were not significantly different between the two groups. Tumor involvement of the pancreatic duct was identified as a risk‐reducing factor for pancreatitis, while an FCSEMS diameter of 6 mm was not identified as a risk factor for RBO and stent migration.

Stent‐related NER was not significantly affected by FCSEMS diameter. Further studies are needed to confirm the usefulness of 6‐mm diameter FCSEMS for preoperative biliary drainage in patients with borderline resectable pancreatic cancer.