Sclerosing hemangioma of the lung: an ultrastructural study.

A well-circumscribed nodular mass was excised from the lingula of the left lung of a 40-year-old-female. The lesion was discovered on routine chest x-ray examination and corresponded to a typical "sclerosing hemangioma" described by Liebow and Hubbell. Electron microscopic study revealed unequivocal epithelial cells in both the irregular spaces and the solid areas of the tumor; some of these cells were identical to granular pneumonocytes. The true vascular component was sparsely distributed. We concluded that "sclerosing hemangioma" was a misnomer because we were dealing with an essentially epithelial lesion.