Large pancreatic pseudocyst penetrating into posterior mediastinum

: We report a rare case of a large mediastinal pancreatic pseudocyst compressing the left atrium and the esophagus and causing dyspnea, palpitations, and emesis. Chest radiograph was non-diagnostic, esophagogastroduodenoscopy showed diffuse extrinsic compression of the distal esophagus and gastric corpus, but a definitive diagnosis was confirmed by computed tomography. We decided to perform surgery due to the recurrence of the pancreatic pseudocyst, a history of unsuccessful radiologically guided external drainage a few years earlier, and a very large diameter of the pseudocyst causing acute cardio-pulmonary distress syndrome.