Fine Needle Aspiration Cytology on Solitary Fibrous Tumors of the Pleura

흉막의 고립성 섬유성 종양의 세침 흡인 세포학적 검색

Localized or solitary fibrous tumor (SFT) of the pleura has been classified as a type of mesothelioma, arising from the submesothelial connective tissue cells. The preoperative diagnosis of the tumor at the cytologic or histologic level is very important for the proper handling of the lesion. This preoperative diagnosis is now possible by means of the advance in the transthoracic fine needle aspiration biopsy (FNA) techniques and in the very experience of the cytopathologists. We describe FNA cytologic feature of two cases of SFT arising from the pleura. Cytologic, histologic, immunohistochemical, and electron microscopic characteristics of pleural SFT are discussed. The tumor cells of SFT are spindle or oval in shape with a variable amount of cytoplasm. They are arranged in irregular trabeculae intimately associated with capillaries. A unique cytologic feature observed in this tumor is that thick, eosinophilic, amorphous collagen bundles are scattered between tumor cells.