To determine the clinical presentation of patients with malignancies metastatic to the lung, the diagnostic utility of fiberoptic bronchoscopy (FB), and the primary site of malignancies metastasizing endobronchially, we retrospectively reviewed 1,853 FB records (1987 to 1991) and selected 111 cases for review. Cases were divided on the basis of FB findings into abnormal (44 patients) and normal (67 patients). Pulmonary symptoms (cough, hemoptysis, and chest pain) prompted referral significantly more often in the abnormal FB group (34/44) than in the normal FB group (24/67). The finding of atelectasis on chest radiograph occurred more frequently in patients with endobronchial abnormalities. The spectrum of extrapulmonary malignancies that metastasize endobronchially has changed during the AIDS epidemic. Our study shows the most frequent causes of endobronchial mass lesions were Kaposi's sarcoma and the lymphoma group (Hodgkin's disease, nonHodgkin's lymphoma, chronic lymphocytic leukemia) and the most common malignancies causing submucosal metastases were breast and the lymphoma group. In summary, the highest yield from FB can be expected in patients experiencing symptoms of cough or hemoptysis and/or having radiographic evidence of atelectasis. We propose a new mnemonic "KLAS" (Kaposi's sarcoma, Lymphoma, Adenocarcinoma, Sarcoma) to describe the malignancies most likely to metastasize endobronchially in the 1990s.