Effects of Androgen Deprivation for Prostate Cancer
Hormone therapy for patients with prostate cancer is a highly effective treatment which can give men with recurrent prostate cancer up to 10-15 years of survival. The removal of testosterone activity may be associated with side effects as detailed below.
- Bone density – For every year of androgen deprivation therapy, patients may lose between 5-10% of their bone density. Up to 20% of men will suffer a fracture.
Management of bone loss – cease smoking, calcium and vitamin D, oral or intravenous
bisphophates (inhibit osteoclasts), weight lifting, exclude other causes of bone loss eg hyperthyroidism. - Anaemia – Men can suffer up to 10-20% loss of red blood cells. This can be associated with symptoms including fatigue, shortness of breath, and decreased exercise tolerance. Some patients may require treatment with erythropoietin.
- Sexual dysfunction – it must be remembered that up to 30%o of men in the age group for prostate cancer already have erectile dysfunction before their diagnosis with prostate cancer. Up to 90% of patients on androgen deprivation therapy will be affected by decreased libido, erectile dysfunction, penile atrophy and testicular atrophy. Medical approaches including 5 phosphodiesterase inhibitors such as Viagra and Cialis every 2-3 nights can assist in maintaining blood flow through the penis and diminish the progression of this problem. Other techniques such as the use of a penile vacuum pump may also be useful.
- Hot flushes/flashes – about 2/3 of men on LHRN atagonists will suffer hot flashes. The cause is not understood. Low dose antidepressants such as venlafaxine (Effexor) and fluoxetine (Prozac) – 30% improvement, paroxetine (Aropax) – 75% improvement, have proven to be helpful. Megace – up to 85% improvement, and the use of cyproterone acetate have also been Shown to be effective in decreasing the severity of hot flashes. Acupuncture may also assist in decreasing symptoms.
Supplements proposed to reduce hot Flashes in women include- American or Asian Ginseng (Panax quinquefolius or panax ginseng)
- Beta-sitosterol (compound found in saw palmetto-serenoa repens)
- Bioflavonoids (found in grapefruit and other fruits)
- Evening primrose oil ( Oenothera biennis)
- Black cohosh (Cimicifuga racemosa)
- Blue cohosh (Caulophyllum Thalictroides)
- Chasteberry (Vitex agnus-castus)
- Dong quai (Angelica sinensis)
- Flaxseed (Linum usitatissimum)
- Hops (Humulus lupulus)
- Licorice (Glycyrrhiza glabra)
- PC-SPES (mixture of 8 herbs – some are estrogenic)
- Red clover ( Trifolium pretense)
- Soy ( Glycine max)
- Thyme ( Thymus spp)
- Tumeric ( Curcuma longa)
- Verbena (Verbena spp)
- Vitamin E (tocopherols)
- Wild yam ( Dioscorea villosa)
- Muscle atrophy – exercise is main strategy to combat the wasting of muscles which may occur with the withdrawal of testosterone.
- Metabolic syndrome – (sugar and cholesterol) – increased fasting blood sugars and cholesterol. Dietary changes needed.
- Gynaecomastia – moderate to severe in 15% of men with LHRH agonists such as Lucrin and Zoladex and 40-70% of men with antiandrogens such as cyproterone. Can be permanent. May be treated with radiation to the breast tissue or medications such as tamoxifen ( associated with risks such as DVT and hot flashes) or a class of drugs known as aromatase inhibitors.
- Cognition – controversial. Can use exercise and strategies such as intermittent androgen deprivation.
- Depression – consider medical treatment, treat the individual side effects and quality of life effects of androgen deprivation to avoid depression.
- GI upset – diarrhoea may be managed by dose adjustment, use of medications such as Imodium. The loose bowel motions tend to settle with time.
- Liver toxicity with antiandrogens – occurs in 5-10%, check liver enzymes regularly. Rarely seen after first year of treatment.
- Fatigue – fatigue can be related to a number of causes including inactivity, depression, low red
blood cell counts and poor sleep. Manage with dietary modification to increase intake of high energy foods. Consider dietary supplements such as L-carnitine.