Outcomes of endoscopic treatment for malignant biliary obstruction in patients with surgically altered anatomy: analysis of risk factors for clinical failure

Background To evaluate the outcomes of endoscopic retrograde cholangiopancreatography (ERCP) for malignant biliary obstruction (MBO) using short-type double-balloon enteroscope (sDBE) in patients with surgically altered anatomy. Methods A total of 45 patients with surgically altered anatomy underwent ERCP using sDBE for the treatment of MBO between April 2011 and March 2019. We retrospectively evaluated the clinical and technical success (insertion and biliary intervention success), adverse events, and risk factors for clinical failure. Results The scope was successfully inserted in the target site in 82.2% of patients (37/45), and among them, biliary intervention success was achieved in 86.4% (32/37). The overall technical success rate was 71.1% (32/45) and clinical success rate was 68.9% (31/45), with an adverse event rate of 11.1%. In multivariate analysis, the presence of peritoneal dissemination (odds ratio, 7.3; 95% confidence interval, 1.5–43.5, p = 0.02) was as an independent risk factor for clinical failure. The clinical success rate was 38.5% in patients with peritoneal dissemination and 81.3% in those without peritoneal dissemination. Conclusion Endoscopic treatment using sDBE in patients without peritoneal dissemination provided favorable outcomes, and it can be an initial treatment for MBO in patients with surgically altered anatomy. Endoscopic biliary stent placement with endoscopic retrograde cholangiography (ERCP) for the treatment of malignant biliary obstruction (MBO) has been widely accepted as an effective drainage method because it is less invasive and safe and has a high success rate (1–3). However, MBO is treated using percutaneous transhepatic biliary drainage (PTBD) or surgical bypass because of difficulties related to endoscopic access to the bile duct following gastrointestinal reconstruction. However, these methods are associated with marked adverse event (AE) rates [1,2,3]. Recently, balloon-assisted endoscopy (BAE) facilitates ERCP in patients with surgically altered anatomy. As for a double-balloon enteroscope (DBE), a short-type DBE (sDBE) is especially useful because it allows the use of many standard ERCP accessories. The success rates of reaching the target site and ERCP-related interventions associated using these endoscopes range from 73–100% and 85–100%, respectively [4, 5]. We previously reported that the success rate of reaching the target site and biliary intervention was 93.8% and 95.7%, respectively, in patients with benign hepaticojejunostomy (HJ) anastomotic stricture [6]. However, inaccessibility of the target site may occur due to severe postoperative adhesions or a long insertion time (i.e., > 60 min). Furthermore, previous reports have shown that the success rate of BAE in MBO cases was significantly lower than that in benign biliary diseases [7, 8]. Few reports have investigated the outcome of BAE for MBO in patients with surgically altered anatomy. Additionally, the risk factors for clinical failure are not well-established. Thus, we retrospectively evaluated the outcomes of endoscopic treatment for MBO using sDBE in patients with surgically altered anatomy and identified risk factors for clinical failure