Extralobar pulmonary sequestration showing high CA 19-19 levels.

We report a case of 40 year-old woman with left thoracic pain who was diagnosed as having a cystic mass located posteriorly at the basis of the left pleural cavity. The preoperative serum CA 19-9 level was increased (2 900 IU/mL). Further investigations did not find neoplastic lesions in the gastrointestinal tract. The intraoperative finding of an anomalous systemic arterial supply to the mass suggested the diagnosis of extralobar sequestration, confirmed at the histopathological examination. The association between pulmonary sequestration and increased tumor markers levels is overlooked in western literature, but it is often reported by many Japanese authors. This case report would underline the practical usefulness for preoperative diagnosis of pulmonary sequestration, when the CT-scan does not demonstrated an anomalous systemic vessel. The common embryogenic origin of both respiratory and digestive apparatus can explain the increased levels of tumor markers such as CA 19-9 and carcinoembryonic antigen in bronchogenic cyst, intestinal duplication and pulmonary sequestration.