A 60-year-old man was given a diagnosis of pulmonary and ocular sarcoidosis. His radiological abnormalities and visual disturbance resolved after two years. Ten years later, at age 70, squamous cell carcinoma was detected in the right lower lobe of the lung. Lymphocyte CD4/8 ratio in bronchoalveolar lavage fluid has remained at a high level for the previous 10 years and was 7.41 immediately before the operation. Chest CT and gallium scintigram could not detect abnormalities in mediastinal or hilar nodes. The tumor and right lower lobe were resected with hilar and mediastinal lymph nodes. Histological examination revealed that there were numerous epithelioid cell granulomas in mediastinal and hilar lymph nodes. BALF analysis reflects residual granulomatous inflammation, even if the radiological findings do not show any abnormalities.