OBJECTIVES: I. Determine whether a cytological diagnosis of lung cancer can be obtained more frequently from sputum specimens following inhalation of INS316 compared to specimens obtained following placebo or compared to specimens spontaneously expectorated in patients with untreated lung cancer. II. Assess the relative sensitivity of sputum cytology in the diagnosis of lung malignancies in this patient population using these sputum collection regimens. III. Determine the quantity of macrophages in sputum of these patients using these techniques. IV. Determine if the number of macrophages in sputum obtained by these methods is predictive of the likelihood of obtaining a positive diagnosis of lung cancer in these patients. V. Determine the total amount of sputum expectorated from these patients using these techniques.