[A resected case of bronchogenic cyst of the left hemidiaphragm with elevated serum CA19-9].

A rare case of bronchogenic cyst of the left hemidiaphragm is reported. A 53-year-old woman referred to our institution for an abnormal shadow on chest roentgenogram. Chest X-ray showed a 6 x 6 cm mass in the left lower lung filed. The margin of the mass was clear and the surface was smooth. The lateral view showed a mass on the diaphragm with the extrapleural sign. Chest CT demonstrated the mass as a multi loculated cyst. Celiac angiography demonstrated the branch of the inferior diaphragmatic artery at the margin of the mass. Her serum CA19-9 level was 470 U/ml. The patient underwent surgical exploration. Operative findings showed the smooth surface mass was on the diaphragm covered with pleura. Resected tumor was large as 7.5 x 6.5 x 4.0 cm. The surface was smooth and white-yellowish, and the cut surface presented a multi loculated cyts. Histopathological examination showed a bronchogenic cyst. CA19-9 in the cyst fluid was elevated as 445,900 U/ml. The serum CA19-9 level returned to normal after the operation.