Lung cancer arising in association with middle lobe syndrome.

Middle lobe syndrome, caused mainly by benign inflammatory diseases, such as chronic bronchitis and bronchiectasis, is manifested clinically as a chronic cough with sputum production. The prognosis associated with this syndrome is considered good in most cases which are caused by chronic inflammatory diseases. A patient who developed lung cancer in the course of long-term treatment for right middle lobe syndrome is described. A 63-year-old woman was admitted to our hospital with complaints of right iliac bone pain. She had been treated for chronic bronchitis and bronchiectasis associated with middle lobe syndrome for 16 years before admission. Work-up of a lung adenocarcinoma originating from the right middle lobe disclosed bone metastasis to the illium. Tumorigenesis in association with middle lobe syndrome has not yet been reported, but this first reported case suggests the need to be alert to the possibility.