Secretion of prorenin by a virilizing ovarian tumor

A 53-year-old normotensive, normokalemic female presented with a 6-month history of virilization. Estradiol, LH, FSH, urinary-free cortisol, and DHEA-S levels were normal. Pelvic ultrasound and computerized tomography were also within normal limits. Her serum testosterone (551 ng/dl; nl, 20-70) and plasma prorenin (124 ng AI/ml/hr; nl, less than 50) levels were elevated. At surgery, a lipoid/steroid cell tumor of the right ovary was removed. Postoperative testosterone and prorenin levels were normal. Ovarian tumor cells, in culture, produced large amounts of prorenin. Immunohistochemistry localized prorenin and/or renin to tumor cells. Determining plasma prorenin levels may be a useful adjunct in diagnosing or following patients with nonepithelial ovarian tumors. A larger clinical study of prorenin levels in patients with such tumors is needed.