
<ArticleTitle>Ovarian hyperstimulation without elevated serum estradiol associated with pure <prot>follicle-stimulating hormone</prot>-secreting pituitary adenoma.</ArticleTitle>
<AbstractText>We report a unique case of a 28-yr-old woman with a gonadotroph adenoma secreting <prot>FSH</prot>, presented with ovarian hyperstimulation, without elevation of serum estradiol. She presented with abdominal pain and large ovaries (both 10 cm in diameter) with multiple follicular cysts shortly after discontinuing oral contraceptive pills. She had a supranormal <prot>PRL</prot> level of 71 microg/liter (normal, &#60;20), <prot>FSH</prot> of 8.4-9.2 IU/liter (normal for follicular phase, 2.4-10), <prot>LH</prot> of 0.01 IU/liter (normal, 1.6-9.3), estradiol of 108 pmol/liter (normal for follicular phase, 80-790), and free alpha-subunit level of 0.11 microg/liter (normal, &#60;1.8). A nuclear magnetic resonance study revealed invasive pituitary macroadenoma, 30 mm in diameter. Dopamine agonist (cabergoline) treatment normalized serum PRL but had no affect on <prot>FSH</prot> levels. A transsphenoidal surgery was performed, and most of the adenoma was resected. One month after surgery the patient resumed menstruation, and the hormonal profile included serum <prot>FSH</prot> of 6.3 IU/liter, <prot>LH</prot> of 2.1 IU/liter, estradiol of 156 pmol/liter, and <prot>PRL</prot> of 10 microg/liter. The excised adenoma tissue exhibited intense immunostaining for <prot>FSH</prot> and secreted this hormone to culture medium. Stimulation with <prot>TRH</prot> (both in vivo preoperatively and in vitro study of the excised tumor) had no effect on <prot>FSH</prot> secretion from the adenoma. Estradiol did not suppress <prot>FSH</prot> release from cultured adenoma cells. Patient serum samples showed significant <prot>FSH</prot> bioactivity when tested in a human granulosa cell line. This case is remarkable because the ovarian hyperstimulation related to the <prot>FSH</prot>-secreting adenoma was not associated with high levels of serum estradiol, probably due to insufficient <prot>LH</prot> production by the normal pituitary. Thus, it supports the two-cell, two-gonadotropin theory, that both <prot>FSH</prot> and <prot>LH</prot> are necessary for normal ovarian estrogen production.</AbstractText>
