[Pulmonary cavernous hemangioma--identification of its endothelial cell origin by immunohistological staining]

A 45-year-old woman was referred to our hospital because of a tumorous shadow in the S10 segment of the left lung. A chest computed tomography (CT) scan showed a nodular lesion with a slightly irregular margin and no contrast enhancement. CT-guided aspiration biopsy was tried but did not result in a histological diagnosis. The tumor was excised during video-assisted thoracoscopic surgery. Histological examination of the specimen revealed cavernous hemangioma. Most cells lining the lumen of the cavernous structure stained positively for von Willebrand factor antibody and negatively for anti-epithelial membrane antigen antibody, which suggests that the tumor was associated with endothelium. To the best of our knowledge, this is the first report of a case in which the diagnosis of pulmonary cavernous hemangioma was confirmed with an immunohistological study.