PITUITARY APOPLEXY OF A GONADOTROPH ADENOMA FOLLOWING GONADOTROPIN-RELEASING-HORMONE AGONIST THERAPY FOR PROSTATIC-CANCER

Treatment of prostatic cancer with GnRH agonist is a medical alternati ve to surgical castration, although hyperstimulation of the tumor can occur. We describe an unusual unwanted effect of such a treatment whic h unmasked a clinically silent gonadotroph adenoma. A 62-year-old man developed after the first injection of leuprorelin-depot a sudden intr acranial hypertension, which was related to apoplexy of an unknown pit uitary adenoma. Its gonadotroph origin was recognized after surgery by immunocytochemistry. Retrospectively, the tumor was shown to secrete in vivo both FSH and LH when on therapy with the agonist, demonstratin g the lack of desensitization. Testosterone levels were also markedly and sustainly high when on therapy, a particularly unwanted effect in prostatic cancer. As gonadotroph adenomas occur in men in the same age group as prostatic cancer, the question is raised whether hormonal te sting and pituitary imaging should be performed before starting a ther apy with GnRH agonist in men. (C)1997, Editrice Kurtis.