THE WIDESPREAD USE of chest roentgenography and the rising incidence of intrathoracic neoplastic disease have combined to produce a more acute clinical awareness of lung tumors. When the chest x-ray is found to contain an abnormal shadow which blends with the mediastinum, a diagnosis of neoplastic disease is often entertained. The available nonsurgical, clinical tools used to confirm or deny this impression are bronchoscopy, fluoroscopy, laminography, I 131scanning, and angiocardiography. Unless contrast visualization of the mediastinal mass is attempted, the vascular nature of some of these shadows w ill be overlooked.
In this large general hospital patients have been encountered in whom a positive blood serological test for Syphilis was present, but in whom the mediastinal mass proved to be neoplastic. We have also seen patients in whom the mediastinal mass was thought to exhibit epansile pulsations but was proved to be neoplastic. we have also seen patients in whom