Synchronous Double Lung Cancer Associated with Idiopathic Pulmonary Fibrosis Detected as a Result of Pneumothorax

Background. We report a case of synchronous double lung cancer which developed in the clinical course of idiopathic pulmonary fibrosis. Case. A 70-year-old man, who was given a clinical diagnosis of idiopathic pulmonary fibrosis, was admitted because of right spontaneous pneumothorax. Tube thoracostomy for continuous drainage was performed but failed to obtain complete re-expansion. Right video-assisted thoracoscopic surgery was undertaken and the upper lobe abnormal mass was resected. The pathological diagnosis of the resected specimen was squamous cell carcinoma. Because a nodule in the periphery of the left upper lobe was also found on chest CT, it was subsequently resected, and found to be squamous cell carcinoma. There were no metastatic lesions, including hilar or mediastinal lymph nodes, or in extrathoracic organs. Synchronous double lung cancer associated with idiopathic pulmonary fibrosis was diagnosed. Conclusion. Synchronous double lung cancer should be considered in patients with idiopathic pulmonary fibrosis.