Spontaneous fistulization of a giant pancreatic pseudocyst into the duodenum following acute pancreatitis: a case report.

Introduction: Pancreatic pseudocysts are well-recognized sequelae of pancreatitis, but giant pseudocysts (>10 cm) are uncommon and rarely resolve through spontaneous fistulization. Spontaneous internal rupture into the gastrointestinal tract happens in less than 3% of cases and typically requires surgical or endoscopic intervention. Case presentation: We report the case of a 40-year-old male with a history of alcohol use who developed a giant pancreatic pseudocyst (22 × 12 cm) following acute pancreatitis. He presented with abdominal discomfort, early satiety, and vomiting. Imaging revealed a massive cyst compressing the stomach and duodenum. Although initially managed conservatively, the patient later experienced episodes of severe abdominal pain and coffee-ground vomiting. Clinical discussion: Spontaneous internal drainage of a giant pancreatic pseudocyst into the duodenum is very rare. This case highlights the potential for non-operative management in carefully selected, clinically stable patients, despite the size of the lesion and the risk of complications. Conclusion: We describe an unusual case of a giant pancreatic pseudocyst that resolved spontaneously through cystoduodenal fistulization. Conservative management led to full recovery, underscoring the importance of individualized treatment strategies in pancreatic pseudocyst management.