Endoscopic Cystogastrostomy and Necrosectomy with Lumen Apposing Metal Stents (LAMS) for Large Pancreatic Walled Off Necrosis: A UK District General Hospital Experience 

This retrospective study was conducted at a district general hospital in South London between October 2024 and October 2025. Patients with large WON (≥10 cm) were identified and reviewed. Management consisted of endoscopic cystogastrostomy using LAMS, followed by endoscopic necrosectomy when required. Data collected included demographics, aetiology of pancreatitis, indications for drainage, procedural outcomes, complications, and recurrence. Continuous variables were summarised using mean, median, and range; categorical variables were expressed as frequencies and percentages. Ethical approval was obtained from the local institutional review board, and all data were anonymised. 

10 patients were included (mean age 51.8 years; range 22–66 years; 7 males, 3 females). The predominant causes of pancreatitis were alcohol related (50%) and gallstone pancreatitis (30%), with autoimmune and post ERCP pancreatitis each accounting for 10%. Pseudocyst/WON size on initial CT ranged from 10 to 20 cm (median 15 cm; mean 15.4 cm). 

Drainage was indicated primarily for sepsis (90%) and less commonly for abdominal pain (10%). Clinical success was achieved in all cases (100%), with a technical success rate of 90%. Complications occurred in 20% of patients, mainly stent migration; no bleeding or severe infections were observed. One patient experienced recurrence of fluid collection 8 weeks after stent removal (5 cm in diameter). 

Three patients (30%) required endoscopic necrosectomy, with a mean of 2.7 sessions and a median of 2 sessions among those treated. While most patients did not require necrosectomy, those who did typically needed 2–3 sessions. WON resolution ranged from 8 to 32 weeks (median 14 weeks; mean 16.2 weeks). LAMS sizes used were 15 × 10 mm in 70% of cases and 20 × 10 mm in 30%. Double pigtail stents were used in 30% of patients. 

Endoscopic cystogastrostomy with LAMS, supplemented by endoscopic necrosectomy when required, is a safe and effective treatment for large pancreatic walled off necrosis and pseudocysts (≥10 cm), even in a district general hospital setting.  This approach demonstrated high clinical and technical success rates with positive patient outcomes. Careful patient selection standardised follow up with imaging and outpatient review, and timely targeted endoscopic therapy are essential to optimise outcomes and sustain long term resolution.