Endocrine Abstracts

Virilization in post-menopausal women is usually the result of androgen production by ovarian or adrenal tumours. Androgen secreting tumours account for less than 1 % of all ovarian tumours and include granulosa cell tumours, thecomas, lipoid cell tumours and luteomas. We present a case of an occult virilizing ovarian luteoma diagnosed by selective ovarian venous sampling.

A 68 year old nulliparous woman presented with a 15 month history of hirsutism and deepening of voice. Examination revealed clitoromegaly and excess hair growth in androgen dependent areas .The degree of hirsutism was severe as assessed by a Ferriman-Gallwey score of 27. The patient had previously had an abdominal hysterectomy and left oophorectomy for menstrual disturbance. Serum testosterone was raised at 7.3 nmol/l(ref:0.7-2.8)and gonadotrophins were post-menopausal(LH 27 IU/L; FSH 47 IU/L).17-Hydroxyprogesterone and urinary free cortisol excretion were normal.Serum testosterone failed to suppress during a 48 hour low dose dexamethasone suppression test. Abdominal CT scans of the adrenal glands and right ovary were normal.

Selective ovarian and adrenal venous sampling was done to determine the source of raised testosterone. Testosterone levels in the high IVC and right and left adrenal veins were 5.7,5.8 and 6.8 nmol/l respectively. Testosterone at the right ovarian vein was 52 nmol/l compared to a peripheral level of 4.6 nmol/l. The high testosterone gradient at the right ovarian vein was suggestive of a testosterone secreting ovarian tumour. The patient subsequently underwent a laparoscopic oophorectomy. Histology of the excised ovary showed stromal luteoma. Postoperatively, serum testosterone levels fell to 1.6 nmol/l.

Stromal luteomas are a rare cause of virilization and hyperandrogenism in postmenopausal women .They are small tumours and are often not detected on imaging .This case highlights the importance of selective ovarian venous sampling in the investigation and detection of these uncommon tumours.