Spontaneous pneumothorax. A complication of lung cancer?

Among 338 adults (258 men and 80 women) presenting with spontaneous pneumothorax, there were six men with lung cancer: five squamous cell carcinoma and one oat cell carcinoma. Pneumothorax led to the diagnosis in five cases and the remaining occurred as a complication of known neoplastic disease. The average age was 67 years. We analyze these six cases, along with 46 others from the literature. In patients less than 40 years old with normal chest x-ray film findings after lung expansion, further investigation for neoplastic disease is not justified. However, heavy smoking, chronic bronchitis, bullous emphysema and incomplete lung expansion after chest drainage in patients over 40 years old are indications for cancer screening through sputum cytologic study, bronchoscopic examination and surgical exploration. The occurrence of a pneumothorax neither alters the treatment of the underlying disease nor modifies the one-year prognosis. Five-year survival is nil, suggesting that lung cancers present as pneumothorax at an advanced stage of disease.