Ectopic pancreas tissue appearing in a mediastinal cyst

Abstract

Heterotopia of pancreatic tissue is a common developmental anomaly. Although ectopic pancreatic tissue is mostly found in the gastrointestinal tract, localization in the mediastinum is extremely rare. We report a 32-year-old male patient who had an urgent thoracotomy two years ago due to a thoracic surgery. During the thoracotomy fragments of a partly necrotic cystic mass in the right thorax were removed and decortication was performed. Two years later the patient was hospitalized again because of haemoptysis and atypical chest pain. A residual cystic mass was detected between the right hilum and the ascending aorta connecting to the pericardium, the superior vena cava and the aorta on the chest CT. After the operation a mediastinal cyst was diagnosed, with a pancreatic tissue by histology.

Figure 1

Chest CT -The arrows show the residual cystic mass detected between the right hilum and the ascending aorta connecting to the pericardium, the superior vena cava and the aorta on chest CT (A,B).

Figure 2

Angiography - showed some blood supply of the cyst from the right internal thoracic artery but not from the coronary arteries.

Figure 3

HE-stained sections made of the specimens showed mature pancreas tissue within the wall of the cyst (A). Immunohistochemistry highlighted the cytokeratin positive ducts and chromogranin positive Langerhans inslets (B,C).