Association of pulmonary sequestration with elevated serum cancer antigen 125 levels: a case report.

Pulmonary sequestration is a rare congenital lung anomaly that is characterized by a nonfunctioning pulmonary parenchyma, which typically lacks connection to the tracheobronchial airways, and thus has an anomalous systemic blood supply. Here we report the case of a 37-year-old man who was diagnosed with pulmonary sequestration and also presented with high levels of the serum tumor marker cancer antigen 125 (CA125). Computed tomography of the chest indicated the presence of a heterogeneous mass with low attenuation in the right S10 region that had a single aberrant artery supplying blood from the descending aorta. The patient eventually underwent thoracoscopic surgery with resection of the right sequestrated lung. Immunohistochemistry showed positive staining for CA125 in bronchial epithelial and epithelioid cells. After surgery, CA125 levels returned to the normal range. In summary, this report describes a case of pulmonary sequestration associated with elevated serum CA125 levels, and further provides relevant literature for this presentation.