PRIMARY MALIGNANT FIBROUS HISTIOCYTOMA OF THE LUNG - REPORT OF A CASEWITH BRONCHIAL BRUSHING CYTOLOGIC FEATURES

BACKGROUND: Malignant fibrous histiocytoma (MFH) arising primarily in the lungs is rare, and a preoperative diagnosis, as well as a surgical planning, is very important because of the tumor's propensity for vas cular invasion and its low incidence of lymph node metastasis. The cor rect preoperative diagnosis of thoracic MFH is not easy to establish b ecause the small fragments from needle and transbronchial biopsies are often inadequate for a conclusive histologic analysis. A preoperative bronchial brushing cytology suggestion of the diagnosis of primary MF H of the lungs may be helpful in such cases. CASE: A 37-year-old male presented with a large, irregular mass in the inferior and middle lobe s on chest as well as on computed tomography. Two bronchoscopies were performed, with the diagnosis of undifferentiated lar,large cell carci noma. After surgical resection a move sophisticated pathologic analysi s, including immunohistochemical and ultrastructural studies, revealed a primary MFH of the lungs. Revision of the bronchial brushing cytolo gy disclosed many spindle-shaped cells with It ''comet'' configuration , strongly suggestive of MFH. CONCLUSION: The bronchial brushing cytol ogy features of spindle-shaped and bizarre, multinucleated giant cells with a comet appearance may be the key to the cytomorphologic diagnos is of MFH.