Granulocytic sarcoma of the tracheobronchial tree: bronchoscopic and pathologic correlation.

Granulocytic sarcoma (GS) is an extramedullary, solid tumor composed of immature granulocytic cells, which occurs in association with myeloproliferative or leukemic disorders. GS can precede, accompany, or complicate the presence of hematologic malignancy in the blood or bone marrow. The anatomic distribution commonly includes bone, nerve, lymph node, and skin, but may involve a variety of soft tissues. Pulmonary involvement is uncommon but may invade the parenchyma, pleura, mediastinum, and airways. We report a rare case of endobronchial granulocytic sarcoma with bronchoscopic and pathologic correlation.