Hypernephroma and hypertension. Two case reports.

Evaluation for hypertension revealed a hypernephroma in two patients and increased plasma renin concentrations (PRC) of 2.8 and 3.1 GU . 10(-4)/ml, respectively. In one of the patients, bilateral renal venous catheterization showed lateralization of PRC toward the tumor side in the ratio 10:3. She had secondary hyperaldosteronism with a plasma aldosterone concentration (PAC) of 738 pmol/l, and hypokalemia with a serum potassium level of 3.0 mmol/l. In the other patient, who had malignant hypertension, PAC was not measured but serum potassium was subnormal (3.3 mmol/l). After nephrectomy, blood pressure (BP), PRC and serum potassium returned to normal in both as did PAC in one of the patients. At regular follow-ups through one year after nephrectomy, BP, PRC, PAC and serum potassium remained normal and metastases were not discovered. The increased incidence of hypernephroma in hypertensive patients underscores the importance of acknowledging this possibility during evaluation for hypertension.