[A case of double bronchogenic cysts in the mediastinum]

A 42-year-old house wife had suffered from abnormal mass lesion in the right pulmonary hilum on her chest X-ray film. MRI showed another mediastinal mass between IVC and descending aorta with high T1 and T2 intensity. Thoracic CT done before MRI missed the latter lesion because only upper mediastinal scanning had been performed. At operation subcarinal and right paraesophageal cysts were successfully removed. Histological examination of the subcarinal cyst showed ciliated pseudostratified columnar epithelium lining, and its thin wall consisted of partly smooth muscle bundle, lymph node, calcification, inflammatory cell infiltration and hemorrhage. The paraesophageal cyst lined by a ciliated pseudostratified columnar epithelium, and the wall consisted of mostly fibrous connective tissue with partly smooth muscle bundle. Although the both cysts were diagnosed as bronchogenic origin, definitive bronchial glands and cartilage could not be recognized. The postoperative course was uneventful. This is the first case report of mediastinal double bronchogenic cysts appeared in the Japanese literature.