AB 31. Solitary fibrous tumor (SFT) of the lung: review of five cases

Background: Solitary fibrous tumor (SFT) of the pleura and the lung is an uncommon spindle cell neoplasm, usually presented as a peripheral mass, arising from the visceral pleura in the majority of the cases. Inward growth into the lung’s parenchyma is rare. The tumor is common during the fifth and sixth decades with no sex predominance. We describe five cases diagnosed to our department as solitary fibrous tumor (SFT) of the lung.
Patients and methods: For the past ten years, five patients, from 46 to 67 years old, were presented to our hospital with intrapulmonary, wellcircumscribed nodule. Thus, due to a diagnostic confirmation of the pulmonary nodule, surgery was performed and the lesion was removed in all five cases.
Results: Histologically, the tumors were characterized by the coexistence of hypo- and hypercellular areas, separated by fibrous stroma which had haemangiopericytoma-like branching blood vessels. The hypercellular areas were composed of bland spindle cells arranged in short intersecting fascicles, creating storiform arrays. The hypocellular areas presented myxoid changes in some cases. Immunohistochemical stains for CD34 and bcl-2 were positive in all cases. Morphological and immunohistochemical findings consistent with solitary fibrous tumor (SFT) of the lung.
Conclusions: Solitary fibrous tumor (SFT) of the lung is an uncommon mesenchymal tumor entity. Although rare, the diagnosis should be considered in asymptomatic slow growing pulmonary nodules. Resection with clear margins is the main important prognostic factor.