[Bronchiolo-alveolar cell carcinoma arising after active pulmonary tuberculosis' report of two cases]

We report on two patients diagnosed as having active pulmonary tuberculosis who later developed lung cancer. In both cases, the lung cancer was detected during the treatment of pulmonary tuberculosis. Both patients were initially considered to be experiencing exacerbation of pulmonary tuberculosis. Case 1 was seen in a 74-year-old man. His chest roentgenogram revealed microscopic cavitary lesions with infiltration into both lung fields. His sputum tested positive for acid-fast bacilli. Although he was treated with isoniazid (INH), rifampicin (RFP), ethambutol (EB) and pyrazinamide (PZA), his general condition deteriorated, and the infiltrative shadows in the lung fields had expanded on subsequent chest radiography. Transbronchial lung biopsy (TBLB) yielded findings compatible with a diagnosis of bronchiolo-alveolar cell carcinoma. Case 2 occurred in a 52-year-old man. His chest radiograph revealed cavitary lesions with infiltration into both lung fields. His sputum also tested positive for acidfast bacilli. Despite medication with INH, RFP, EB and PZA, the infiltrative shadow in his chest radiograph increased in size. Bronchiolo-alveolar cell carcinoma was confirmed after examination of the sputum cytology. Case 1 was diagnosed as lung cancer 10 months after being admission to the hospital, and Case 2, seven months after hospitalization. Recent discussion concerning the simultaneous occurrence of pulmonary tuberculosis and bronchogenic carcinoma suggests a high frequency of coexistence of the two diseases. However, the coexistence of active tuberculosis with bronchiolo-alveolar cell carcinoma, as in our cases, is rare.