Extensive pancreatic heterotopia in distal esophagus mimicking esophageal malignancy

We report an unusual and rare case of a young adult patient with extensive symptomatic pancreatic heterotopia in the distal esophagus that appeared on imaging as a malignant tumor. After comprehensive preoperative workup, the soft tissue mass was treated surgically according to intraoperative histology that revealed its benign nature.

A young male patient with worsening epigastric pain, gastroesophageal reflux, and weight loss presented in a university hospital for a comprehensive diagnostic workup. Apart from clinical examination and laboratory tests, he underwent gastroscopy, esophageal manometry, endoscopic ultrasound, barium meal study, computed tomography (CT), and positron emission tomography (PET-CT). Finally an interdisciplinary board recommended surgical removal of a mediastinal mass and final diagnosis was reached by intraoperative histology.

The clinical examination and laboratory test were unremarkable, esophageal manometry suggested achalasia due to simultaneous spastic and retrograde contractions with high amplitude. Barium meal showed mild compliant stenosis of the distal esophagus, but gastroscopy found no explanation. CT and later also PET-CT revealed a large soft tissue mass with avid accumulation of ¹⁸F-fluorodeoxyglucose surrounding the distal esophagus. Endoscopic ultrasound was very limited and no representative tissue samples were obtained prior to surgery. The surgeon accessed the mediastinum through the left thoracotomy and found a noncompliant well-defined mass surrounding the distal esophagus. Intraoperative histology showed nothing but common structures of pancreatic tissue.

A large soft-tissue mass of pancreatic heterotopia in the distal esophatus is extremely rare and preoperative workup inconclusive. Only surgical exploration and (intraoperative) histology are in a position to reveal its true nature.