["Pneumocytoma" or "sclerosing hemangioma": histogenetic aspects of a rare tumor of the lung].

Aspects of histogenesis and nomenclature of so called "sclerosing hemangioma" of the lung (WHO 1999) are discussed and compared with immunohistochemical findings in eight examined operation specimen. The lesion is characterised by the presence of typical surface cells, which can be related to type II pneumocytes. Progesterone-receptor positive stromal cells may derive from primitive mesenchymal cells. Endothelial proveniance of tumor cells could not be confirmed by immunohistochemistry. Therefore, this rare usually benign pulmonary neoplasm should be entitled "pneumocytoma" analogous to the suggestion of several other authors.