Two cases of small sized lung cancer detected at the time of spontaneous pneumothorax

Pneumothorax complicated with lung cancer is rare and we report here two cases of lung cancer detected at the time of pneumothorax. Both cases were incidentally found by chest X-ray and chest computed tomography during the treatment of pneumothorax. One patient was a 74-year-old man who developed left pneumothorax three times, a mass subsequent to which 20mm in diameter was detected on the right side. Left bullectomy was performed followed by partial lung resection for lung cancer 3 weeks later. The other patient was a 67-year-old man who developed left pneumothorax. After reexpansion of the left lung, chest CT showed a peripheral small nodule near a bullous lesion in the left lower lobe (S6). Frozen sections revealed lung cancer, and lobectomy with mediastinal lymphadenectomy was performed in one procedure to treat both pneumothorax and lung cancer. Both patients were heavy smokers. It is important to consider the possibility of the presence of lung cancer in patients who develop pneumothorax, particularly in elderly patients who are heavy smokers.