Airway carcinoembryonic antigen concentrations in patients with central lung cancer or chronic bronchitis

To determine the clinical utility of airway carcinoembryonic antigen (CEA) concentrations to distinguish malignant from inflammatory airway disease in patients undergoing bronchoscopy, we determined CEA concentrations by enzyme immunoassay in bronchial washings recovered in 48 subjects, including 20 patients with central lung cancer, 18 patients with chronic bronchitis, and ten nonsmoking patients with a diagnosis of pneumonia or peripheral granuloma. Concentrations of CEA in bronchial washings were standardized by using the total protein concentration in recovered fluid (CEA/TP). Concentrations of CEA were significantly increased in bronchial washings recovered from both patients with chronic bronchitis and lung cancer compared with patients with pneumonia or granuloma (252 ± 47 ng/mg and 199 ± 64 ng/ml vs 62 ± 11 ng/mg, SEM, p < 0.005). Airway CEA concentrations in patients with chronic bronchitis were somewhat increased compared with concentrations recovered from a cancer-involved airway (252 ± 47 ng/ml vs 199 ± 64 ng/mg, SEM, p < 0.05). Measurement of airway CEA concentrations is not useful in distinguishing malignant from inflammatory airway disease as airway concentrations of CEA may be markedly increased in patients with both conditions.