Factors Impacting Treatment Outcomes in the Endoscopic Management of Walled-off Pancreatic Necrosis

Ji Young Bang; C Mel Wilcox; Jessica Trevino; Jayapal Ramesh; Shajan Peter; Muhammad Hasan; Robert H. Hawes; Shyam Varadarajulu


J Gastroenterol Hepatol. 2013;28(11):1725-1732. 

In This Article


Patient and WOPN Characteristics

Seventy-six patients underwent endoscopic drainage of WOPN. The median age of patients was 52.2 years, the majority were male, and alcohol was the most common etiology. Laboratory investigations revealed leukocytosis and hypoalbuminemia with a mean CT severity index[16] of 7.6 (Table 1). More than 50% of WOPNs were located in the pancreatic body, and the median size (largest dimension) was 110 mm (Table 2).

Technical Outcomes

At ERCP, pancreatic duct stent placement was successful in 14 (18.4%) patients. Stent placement was unsuccessful in others because of DPDS in 53, gastric outlet obstruction in four, and difficult pancreatic duct anatomy or stricture in five (Table 2). The stomach was the access point for transmural drainage in 85.5% of patients, and more than 75% of procedures were undertaken under EUS guidance.

Treatment Outcomes

Overall, treatment was successful in 53 of 76 patients (69.7%). Transmural drainage was undertaken using MTGT in 18 patients and conventional technique in 58 (Table 2). The treatment success rate for MTGT was significantly better than that for conventional drainage, 94.4% versus 62.1% (P = 0.009) (Table 3). One of 18 patients treated by MTGT required surgery owing to worsening infection and had a successful postoperative course. Reasons for treatment failure in the 22 of 58 patients treated by conventional technique were persistence of WOPN in 16, postprocedural infection in five, and perforation in one. While two of these patients died of multiorgan failure, 20 underwent surgery, with good clinical outcomes in 18 (two patients died of postsurgical complications).

Predictors of Treatment Success

On multiple logistic regression analysis, only MTGT for WOPN drainage (OR 56.2, 95% CI 2.64–1194; P = 0.01) and fewer endoscopic interventions being needed (OR 7.85, 95% CI 1.46–42.2; P = 0.016) were significantly associated with treatment success when adjusted for patient demographics, serum albumin, serum white cell count, Computed Tomogram Severity Index, presence or absence of pancreatic duct stent, and location, size, etiology, and luminal effect of WOPN (Table 4). On reverse stepwise multivariate logistic regression analysis, both MTGT (OR 15.8, 95% CI, 1.77–140.8; P = 0.013) and just a single endoscopic intervention being needed (OR 4.03, 95% CI, 1.16–14.0; P = 0.028) remained significant as predictors of treatment success (Table 4).

Long-term PFC Recurrence

Of the 53 patients with WOPN who had initial treatment success, transmural stents were left in permanently in 29 (54.7%; all with DPDS), and in 24 (45.3%) patients (13/24 had DPDS), the stents were removed (Table 5). At a median follow-up of 26 months, the rate of PFC recurrence was significantly less in patients in whom the stents were not removed as compared with patients in whom the stents were removed (0 vs 20.8%; P = 0.015). Of the five patients who had PFC recurrence, three were managed by repeat endoscopic drainage and two underwent surgery.

Other Long-term Outcomes

Of the 53 patients with initial endoscopic treatment success, 42 (79.2%) had DPDS. One of 11 patients without DPDS died from portal hypertension at 14-month follow-up. Of the 42 patients with DPDS, two required surgery for persistent abdominal pain at a median follow-up of 22 months. One patient underwent a total pancreatectomy with auto-islet transplantation and the other underwent a distal pancreatectomy. Seventeen of 53 patients (32.1%) still required narcotics at a median follow-up of 319 days (IQR 262–371 days).


Procedural complications were encountered in 11 of 76 patients (14.5%). Short-term procedural complications included perforation (n = 1), bleeding (n = 1), and infection (n = 6). While perforation was managed by surgery, bleeding was treated by coil embolization under radiological guidance. Infection was managed by surgery in three patients and by placement of additional transmural stents in two. In three patients with DPDS, the transmural stents migrated, causing small-bowel obstruction in two and lodging within the necrotic cavity in one patient. While one patient with bowel obstruction underwent surgery for stent removal, the stents migrated spontaneously with conservative measures in the other patient. The stent that migrated within the necrotic cavity could not be retrieved by endoscopy, and no further intervention was undertaken in this patient.