A 43-year-old female was admitted to our hospital with mild cough, sputum and right chest pain. The chest X-ray revealed an inhomogeneous shadow in the right upper lung field and mediastinal lymphadenopathy. At first we considered the patient had bronchogenic carcinoma, as her serum CA19-9 and SLX levels were high and the right upper bronchus was obstructed by necrotic tissues. However bronchoscopic specimen showed necrotizing epithelioid cell granulomas and Mycobacterium tuberculosis was detected, and her disease was diagnosed as endobronchial tuberculosis. The case responded well to anti-tuberculosis chemotherapy. The differential diagnosis between bronchogenic carcinoma and endo bronchial tuberculosis was very difficult in this case because of high serum level tumor marker and endoscopic findings, which turned to normal after treatment. We discussed the cause of high serum level of CA19-9 and SLX in nonmalignant lung disease.
