Published: January 2004

Androgen Ablation, Osteoporosis and Prostate Cancer:
GU Tumour Group Guidelines

Osteoporosis is a major health concern in men over 65 years of age and is currently underdiagnosed and undertreated. Most men with prostate cancer are over 65 years of age. Androgen ablation therapy for prolonged periods is also a significant risk factor for inducing osteoporosis. Androgen ablation induced osteoporosis is a potential source of major morbidity, low QOL and mortality. It is entirely treatable and can be stabilised or reversed.

• It is therefore the obligation of a physician who starts patients on androgen ablation to diagnose osteoporosis.
• We recommend Vitamin D (800IU) and calcium supplementation (to a total 1500mg/d) as well as moderate exercise / fall prevention for all men beginning androgen deprivation therapy. See the patient pamphlet: "Guidelines for the Prevention of Osteoporosis…".
•  A baseline BMD should be performed if
  1. prolonged androgen ablation is to be employed defined as > 6 months (adjuvant or palliative)
  2. baseline hypogonadism is found (10) (appendix 1: ); or
  3. if the BMD may affect the choice of treatment in the elderly.
• It is not within the scope of BCCA practice to routinely screen all men over 65 years of age for osteoporosis. The patient can discuss this matter with their primary care physician.
• This group does not believe that the evidence yet supports treatment to prevent osteoporosis for patients starting androgen ablative therapies. The endpoints of reduction in morbidity, mortality, and skeletal events have yet to be shown in the prophylactic setting of a patient with normal or even mildly osteopenic BMD at baseline.
•  If BMD, history or plain films identify 'osteoporosis' (defined here as a T-score <= -2.5) at any time, the patient should be considered for bisphosphonate therapy. We still lack suitable and large enough trials to prove a reduced fracture risk in men with prostate cancer on AA but stabilisation or improvement in bone density seems to occur. Reduction in fractures does occur with bisphosphonates (alendronate) in primary male osteoporosis and in other iatrogenic osteoporosis.
• The responsibility for the prescription and monitoring of side effects of these drugs can be transferred to another physician who may have greater familiarity with these products and their risks and benefits.
• Furthermore, primary care physicians or specialists may need to screen the patient for secondary causes of osteoporosis and identify steps to reduce fracture risk.
• Arrangements for the monitoring of BMD response rest with the physician who ordered the baseline BMD and prescribed the AA. Mechanisms must be in place to ensure followup studies.
• The importance of BMDs being conducted on the same machine each time is emphasised.
• BMD should be repeated every 2 years in patients who are castrate and have normal BMDs at baseline.
• Earlier followup BMDs can be considered in patients at higher risk e.g. osteoporosis/osteopenia at baseline, or other significant risk factors promoting osteoporosis. These patients may be best managed under specialist care.
• This group recommends that fracture incidence and BMD should be considered as part of any randomised trial involving prolonged androgen deprivation therapies.

This document does not address the possible relationship between high BMD in men and the risk of developing prostate cancer (10). We do not attempt to address the potential use of bisphosphonates in the treatment and prevention of bone metastases (9) (3), as this is under review as a Priorities and Evaluation Committee proposal, submitted recently by Dr. K. Chi.