[Lung cancer with chylothorax successfully treated by chemical pleurodesis with OK-432].

A 66-year-old man was admitted to our hospital because of bloody sputum. Chest computed tomographic scans disclosed a right hilar tumor. A tumor in the right upper-lobe bronchus was detected by fiberoptic bronchoscopy. Microscopic examination disclosed moderately differentiated squamous cell carcinoma. The patient was treated with irradiation and combination chemotherapy. Thereafter, right chylous pleural effusion developed and continued to accumulate. Pleurodesis was induced by the intrathoracic injection of OK-432 at 15 KE per dose. Lung cancer with nontraumatic chylothorax is rare. In our patient, pleurodesis with OK-432 was an effective treatment.