ABSTRACT
Secretory IgA-S content was evaluated in vitro in human normal and tumoral bronchial mucosa from 39 cases. In 75% of the cases, IgA-S production by tumoral tissue was higher than the levels found in control populations. On the other hand, IgA-S synthesis by normal bronchial tissue of patients with lung tumors, particularly with squamous cell carcinoma, was increased in comparison with patients free of neoplastic bronchopulmonary disease, in 30% of the cases. Comparing tumorous tissue with normal mucosa from the contralateral bronchus of the same patient, marked differences in IgA-S patterns were observed. Regarding the results obtained, we could consider the measuring of IgA-S in bronchial mucosa as a valuable diagnostic aid in patients with suspect pulmonary masses.