Small cell lung cancer complicated by pulmonary sarcoidosis

In July 2009, a 69-year-old man was admitted to our hospital because an abnormal chest shadow had been noted on medical examination. Chest radiography and computed tomography showed mediastinal and bilateral hilar lymphadenopathy. Bronchoalveolar lavage fluid (BALF) from the right B(5) revealed an increased CD4/CD8 ratio. Histological examination of the biopsy specimens obtained from the tumor in the left upper bronchus revealed small cell lung cancer, whereas examination of the specimens obtained from the left B(3) revealed noncaseating epithelioid cell granulomas containing giant cells, confirming the diagnosis of sarcoidosis. The patient underwent chemotherapy with carboplatin and etoposide without any steroids. After 4 courses of chemotherapy, bronchoscopic examination revealed that the tumor had shrunk, and the BALF CD4/CD8 ratio had decreased; further, no histological evidence of sarcoidosis was seen in specimens obtained from the left B(3). Concomitant small cell lung cancer and sarcoidosis is rare. Interestingly, cancer chemotherapy might improve pulmonary sarcoidosis.