Carbohydrate antigen 19-9 (CA19-9) has a strong correlation with pancreatic and biliary carcinomas and is widely used as a tumor marker. Resently we sometimes see reports describing that respiratory diseases are associated with an abnormally high level of CA19-9.
In this paper we discribed a case of pulmonary sequestration with the high serum value of CA19-9. A 19-year-old man was referred to the hospital because of the fever and cough. The Chest X-ray revealed a cystic shadow in the right lower lung field. Selective angiography showed an aberrant artery arising from the abdominal aorta, into the bilateral lower lung segment. Right lower lobectomy was performed.
The immunohistochemical study of lung tissues was to be positive CA19-9 staining on the surface of broncheal epitherum. Serum CA19-9 levels gradually decreased and reached the normal serum level after 4 months after surgery. CA19-9 exists in the normal bronchial gland. It is thought that respiratory disease should be considered as a possible diagnosis for elevated CA19-9 level.