Lung scan in the diagnosis of bronchogenic carcinoma

When chest roentgenograms fail to reveal the presence of a lesion in a patient suspected t o have bronchogenic carcinoma, perfusion lung scanning with radioiodinated macroaggregated human albumin (1-131 M.A.A.) is of great help in the diagnosis and localization of the bronchogenic carcinoma. Marked decrease in perfusion of the affected lung area is detected on lung scan in early hilar and parahilar lesions which are not even seen on chest roentgenograms. Two such cases are presented. Lung scan is safe and easy to perform.