Testosterone replacement therapy and prostate/seminal vesicle volume in Klinefelter's syndrome.

Volume of prostate and seminal vesicles was measured in patients with Klinefelter's syndrome by means of transrectal ultrasonography before and after testosterone replacement therapy. Continuous suppression of plasma gonadotropin levels was not observed, and plasma levels of testosterone did not maintain the normal range. However, volume of prostate (p less than 0.001) and seminal vesicles (p less than 0.05) increased significantly after testosterone replacement therapy. Volume determination of prostate and seminal vesicles by means of transrectal ultrasonography is an available parameter for evaluating the adequacy of testosterone replacement therapy in Klinefelter's syndrome.