The significance of individual angiographic features in the evaluation of hypovascular renal lesions. Part I (author's transl)

Fifty malignant and 50 benign renal lesions, with an hypovascular pattern, were classified into four groups on the basis of their vascular morphology. Three of these groups consisted of circumscribed masses distinguished as avascular lesions, lesions with peripheral vascularity and lesions with central vascularity. The fourth group consisted of diffuse or multicentric hypovascular lesions, which were also space-occupying. This grouping confirmed that histologically similar processes can produce widely differing vascular patterns and that they were therefore found in all groups (polymorphy). On the other hand, masses of different aetiology could show practically identical vascular patterns (isomorphy). In order to reduce errors in the diagnosis of hypovascular lesions, the value of individual features was analysed. Part I of this paper deals with the angiographic changes within the tumour. An analysis of the frequency of various phenomena in malignant and benign lesions (total index) permitted conclusions concerning their diagnostic value.