[Angiographic study of peripheral lung field mass lesions by superselective pulmonary arteriography]

Studies of pulmonary arteriography have a long history in the diagnosis of lung tumors (Steinberg and Robb, 1938). The main purpose of these studies was mostly the determination of the resectability of neoplasms. So that the role of pulmonary arteriography on the diagnosis of peripheral lung tumors has yet been obscure. Neither conventional nor selective pulmonary arteriography can clearly visualize vascular structures of mass lesions in the peripheral lung fields, because of overlaid other segmental arteries, dilution of the contrast medium and blood flow shift. In the present study, direct catheterizations to the segmental branches of peripheral lung field mass lesions were performed on 62 cases, in order to visualize and investigate more detailed vascular structures of them. Twenty nine cases were of primary lung cancer; 14 of metastatic and 19 of inflammatory mass. By means of the superselective pulmonary arteriography, vascular wall irregularities and tumor stain were frequently observed in the cases of malignancies. Either occlusion of minute branches (1 mm greater than or equal to) or encasement of pulmonary arterial branches (1 mm less than) was seen more frequently in the cases of primary lung cancers (86%) than in the cases of metastatic lung cancers (64%). Tumor stain was also observed both in the cases of primary lung cancers (55%) and metastatic lung cancers (64%). In the cases of primary lung cancers, tendency for visualization of vascular wall irregularities and tumor stain seemed to depend upon rather their histological types and differentiation grades than the size of the mass. Encasement or obstruction of the arterial branches (1 mm less than) was seen more frequently in the cases of poorly differentiated adenocarcinoma, moderately differentiated squamous cell carcinoma and anaplastic carcinoma than in the cases of other histologic types. On the other hand, tumor stain was observed more frequently in the cases of moderately differentiated adenocarcinoma and anaplastic carcinoma than in the cases of other histologic types. Obstruction of arterial branches (1 mm less than) was seen also in a few cases of the inflammatory masses, but that of inflammatory masses was usually distinguished from that of malignant masses by their characteristic surrounding vascular natures such as central vascular convergence, widespread simple narrowing of arterial branches and diminution or lack of ramification of minute branches. Tumor stain was not observed in the cases of inflammatory masses.