152 consecutive space-occupying renal lesions (54 cancers, 66 single or multiple cysts, 18 pseudotumors, 8 inflammatory lesions, 3 hydronephroses, 3 hematomas) were studied by selective angiography, considering the signs noted in the three phases: arterial, nephrographic, and venous. The frequency of each of these angiographic signs in the different forms of renal pathology was evaluated. Based on this study, pathognomonic angiographic signs were identified for the various types of pathology. For each angiographic sign the 'diagnostic value' was calculated in order to differentiate malignant from benign space-occupying lesions. Dependent on the angiographic phase they are in, these signs constitute the arterial, nephrographic, and venous 'symptom constellation' characteristic of each lesion. The relationship between angiographic signs and either histologic type or size of tumor were analyzed. The causes of false positive and false negatives were investigated. The value of certain angiographic signs for a correct diagnosis of the cases judged as suspect or misinterpreted was discussed.