Fine needle aspiration cytology of pulmonary infarct.

The cytologic features of a pulmonary infarct diagnosed by fine needle aspiration (FNA) cytology are reported in a 54-year-old white man with a prior history of renal transplant surgery. Although the diagnosis of pulmonary embolus was unsuspected, FNA cytology suggested the correct diagnosis, which was confirmed by subsequent radiologic studies. This is believed to be the first reported case of pulmonary infarct diagnosed by FNA cytology. Cytologic features of the entity are discussed along with potential sources for a false-positive diagnosis of malignancy.