[Renin-secreting renal tumor. Apropos of a case with an ultrastructural and immunohistochemical study].

A case of renin-secreting tumor of the left kidney in a 36 year-old man with hypertension of five years duration is reported. The antihypertensive therapy was unsuccessful. Following nephrectomy, blood pressure returned to normal values and is still normal, seven years later. There is no evidence of metastasis. The tumor was studied by electron microscopy and by immunohistochemistry. It is composed of two cellular structures normally encountered in the kidney: renin-secreting cells and cells similar to those of the cortical collecting ducts. This benign lesion might be hamartomatous.