[Radiological aspects of renal metastases. Apropos of 9 cases]

Renal metastases are tumours which are not rare and which may reveal a primary neoplasm previously undiagnosed. The primary tumours identified in the nine cases reported were six squamous cell carcinomas of the bronchus, one carcinoma of the breast, one carcinoma of the thyroid and one meningioblastoma. Signs at intravenous pyelography are variable, with a marked predominance of appearances of infiltration of the excretory passages by the renal mass, with or without direct involvement of the excretory passages. Angiographic signs appear to be related to the nature of the primary tumour with frank hypovascularisation in the metastases of bronchial tumours and hypervascularisation in those of carcinoma of the thyroid and meningioblastoma. Radiological diagnosis is difficult given the absence of specificity of the urological and anglographic signs. Even histologically the diagnosis may be difficult, particularly in the case of primary bronchial tumours-this being the commonest possibility.