Lung Cancer Complicated by Relapsing Polychondritis.

A 77-year-old man presented with a 1-month history of cough, pharyngeal discomfort, and weight loss. Chest radiography revealed a mass shadow in the right upper lung field. Bronchoscopy showed multiple white nodules along the tracheal cartilage ring. Although adenocarcinoma cells were detected in the mass, several biopsy specimens of the tracheal lesions exhibited no malignancy. 18F-fluorodeoxyglucose positron emission tomography revealed an intense accumulation in the mass, nasal septum, and tracheal cartilage. Furthermore, anti-type II collagen antibody levels were elevated. We finally diagnosed him with lung cancer complicated by relapsing polychondritis. Treatment with oral prednisolone was initiated, followed by sequential chemoradiotherapy for lung cancer.