Androgen and metabolic changes after orchiectomy

Abstract

Bilateral orchiectomy reduces serum testosterone, an androgen stimulating the growth and proliferation of both normal and malignant prostate cancer cells. Low testosterone concentrations are associated with obesity, insulin resistance and an adverse lipid profile in men. The aim of this study was to measure the influence of post-orchiectomy changes in serum androgen concentrations on markers for metabolic syndrome. Fasting venous blood samples were obtained at baseline, 3-hourly (1-12 hours) and weekly (1-4 weeks) intervals post-orchiectomy from 10 patients (mean age 73.45 ± 12.7 years) with prostate carcinoma and high serum prostate-specific antigen (PSA) concentrations. Serum testosterone, free testosterone, PSA, insulin, luteinising hormone (LH), follicle-stimulating hormone (FSH), sex hormone-binding globulin (SHBG), dehydroepiandrosterone sulfate(DHEA-S) and glucose concentrations were measured. Serum high molecular weight adiponectin (HMW-A) concentrations and insulin resistance were determined. Baseline waist circumference and weight were compared to values obtained after 4 weeks. For median difference of paired data, 95% confidence intervals (CI) were calculated to measure the significance of differences between baseline and post-orchiectomy results. Compared to baseline, serum concentrations of testoterone, free testosterone, PSA and DHEA-S decreased, and LH, FSH, insulin and insulin resistance increased significantly at different times post-orchiectomy. HMW-A was significantly decreased at 9 and 12 hours and then gradually increased. Serum glucose concentrations remained unchanged. Median weight and waist circumference increased by 3.5 kg and 5 cm, respectively, within 4 weeks. Post-orchiectomy hormonal changes resemble those found in metabolic syndrome.