Massive Pancreatic Pleural Effusion Caused by Intrathoracic Perforation of a Pancreatic Pseudocyst Successfully Managed with Endoscopic Drainage Followed by Thoracoscopic Decortication: A Case Report.

INTRODUCTION: Pancreatic pleural effusion is a rare condition caused by direct leakage of pancreatic fluid into the thoracic cavity, resulting in massive pleural effusion. We report a case of massive pleural effusion due to intrathoracic perforation of a pancreatic pseudocyst successfully treated by thoracoscopic surgery.

CASE PRESENTATION: A 36-year-old man with a history of chronic alcoholic pancreatitis presented with progressive dyspnea and was transported to Bokutoh Hospital. Chest radiography revealed a massive left pleural effusion with mediastinal shift to the right. Emergency thoracic drainage was performed, resulting in symptomatic improvement. Biochemical analysis of the pleural fluid showed markedly elevated amylase levels. Endoscopic retrograde cholangiopancreatography demonstrated contrast leakage from a pancreatic pseudocyst into the left thoracic cavity, leading to a diagnosis of intrathoracic perforation of a pancreatic pseudocyst. Endoscopic nasopancreatic drainage was performed, and subsequent imaging confirmed closure of the fistula. However, residual pleural effusion and impaired lung expansion persisted. Thoracoscopic decortication and drainage were therefore performed on day 17 of hospitalization. Intraoperatively, a large amount of black pleural fluid and thickened inflammatory pleura resembling empyema were observed. The postoperative course was uneventful, and the patient was discharged home on POD 37 without recurrence.

CONCLUSIONS: When pleural effusion is observed in patients with chronic pancreatitis, pancreatic pleural effusion should be considered. Thoracoscopic surgery may be an effective treatment option, particularly in cases with persistent pleural inflammation after successful endoscopic management.