Fine needle aspiration biopsy of solitary fibrous tumor of the pleura. A report of two cases with a discussion of diagnostic pitfalls.

BACKGROUND

The diagnosis of a peripheral pulmonary nodule presents a challenge due to many diagnostic possibilities and pitfalls. We describe the cytologic features of solitary fibrous tumor of the pleura, differential diagnoses, pertinent immunohistochemical stains and histogenesis.

CASES: Two cases of solitary fibrous tumor of the pleura showed two cell populations on cytologic preparations; mesothelial cells and spindle cells. The neoplastic spindle cell component was positive for CD-34 and vimentin but not for cytokeratin.

CONCLUSION

Solitary fibrous tumor of the pleura is rare but should be included in the differential diagnosis of a peripheral pulmonary nodule. Fine needle aspiration biopsy is a safe and rapid method of providing a confirmatory diagnosis.