Early changes in bone metabolism and serum sex hormones in androgen deprivation therapy

摘要

Background: Androgen deprivation therapy (ADT) with luteinizing hormone releasing hormone agonists (LHRHa) is a major treatment modality for prostate cancer (PC), particularly advanced disease. LHRHa induced hypogonadism promotes bone loss, leading to osteoporosis and heightened fracture risk. Most previous studies on skeletal impact of LHRHa employed bone mineral density (BMD) testing. Serum bone-specific alkaline phosphatase (BSAP), an established bone biomarker, is reflective of changes in skeletal metabolism which precede BMD changes. In postmenopausal women, serum BSAP has been associated with fracture risk irrespective of BMD. Setting: Charing Cross Hospital, London, United Kingdom. Methods: We assessed early changes in serum BSAP levels of patients with non-metastatic PC (n=9) undergoing LHRHa therapy. Serum testosterone and estradiol concentrations were also measured. Samples were taken at baseline before the start of treatment and three months afterward. Comparisons were made with blood samples taken at similar time points for age- matched controls without PC (n=9). Results: No significant difference in BSAP levels was seen between groups (p=0.242). Testosterone and estradiol levels were significantly reduced following treatment (p=0.000). No correlation was observed between serum BSAP and serum testosterone (R=0.187, p=0.276) or serum estradiol (R=0.055, p=0.75). Conclusions: Changes in serum BSAP levels may not be evident as early as 3 months following ADT with LHRHa. The study was limited by the small sample size and use of serum BSAP only which is one of the many bone markers. A larger study using multiple bone markers is warranted to determine early effects of LHRHa treatment on bone metabolism.