Gastric cyst of the posterior mediastinum in a child: An unusual presentation

Gastric cyst of the posterior Mediastinum is a rare congenital anomaly of the gastrointestinal tract. They are classified according to their embryological origin, epithelial lining and location, as thymic cyst, cystic hygroma, mesothelial cysts, thoracic duct cyst and cystic malformation of the primitive foregut. They usually present in neonates or in infancy and are discovered incidentally on radiological examination or gastric endoscopy. Accurate diagnosis of these cysts before resection is difficult and differential diagnosis are varied. This case report presents a 6-year-old boy who complained of fever for 3 weeks. Chest X-ray revealed right para median oval shaped opacity. HRCT showed a well-defined cystic lesion measuring 9x4.4x3.3 cm in the right side of the posterior mediastinum in the perihilar location. There was also noted vertebral segmentation anomaly in the cervicothoracic spine. Cystectomy was and Gastric cyst was diagnosed through histopathological examination. This case report is presented for its rarity and an unusual delayed clinical presentation.