Metastatic pulmonary leiomyosarcoma: cytopathologic diagnosis on sputum examination

Pulmonary metastasis of sarcomas is not uncommon. Rarely, endobronchial involvement may result in exfoliation of diagnostic cells in sputum. This case report is of a 71-yr-old man with a history of lower leg leiomyosarcoma who developed multiple lung metastases. Sputum examination revealed malignant cells with pleomorphic, elongated, and cigar-shaped nuclei and occasional bipolar cytoplasmic processes. Immunoperoxidase studies on the smears using desmin and smooth muscle actin were strongly positive, consistent with leiomyosarcoma. Confirmation of metastatic lung disease by sputum cytology not only has prognostic importance but also obviates the need for further investigations.