Androgen suppression therapy

Androgen Suppression Therapy (AST), also known as androgen deprivation therapy (ADT), is a medical treatment primarily used for prostate cancer. It aims to reduce or block the production and effects of androgens, male hormones, in the body. Androgens, such as testosterone, play a crucial role in the development and progression of prostate cancer. By lowering these hormone levels, AST can slow the growth of cancer cells, helping to manage the disease.

Mechanism of Action

AST works by interrupting the androgen signaling pathways that prostate cancer cells rely on for growth and survival. This can be achieved through several methods:

• Gonadotropin-Releasing Hormone (GnRH) Agonists: These drugs, also known as luteinizing hormone-releasing hormone (LHRH) agonists, inhibit the secretion of gonadotropin hormones, which in turn reduces testosterone production by the testicles.
• GnRH Antagonists: Similar to GnRH agonists, these drugs block the action of gonadotropin-releasing hormone at the pituitary gland, leading to a rapid decrease in testosterone levels.
• Antiandrogens: These medications block the action of androgens at their receptor sites in the tissue, particularly in prostate cancer cells.
• Orchiectomy: A surgical procedure that involves the removal of the testicles to significantly reduce the production of testosterone.

Indications

AST is primarily used in the treatment of prostate cancer. It is indicated in various scenarios, including:

• As a primary treatment for advanced or metastatic prostate cancer.
• In combination with radiation therapy for intermediate to high-risk localized or locally advanced prostate cancer.
• As adjuvant or neoadjuvant therapy to other treatments.
• In the management of biochemical recurrence after primary treatment.

Side Effects

While effective in managing prostate cancer, AST is associated with a range of side effects due to the systemic reduction in androgen levels. These may include:

• Hot flashes
• Reduced libido
• Erectile dysfunction
• Osteoporosis
• Muscle mass loss
• Fatigue
• Mood swings
• Increased risk of cardiovascular disease
• Metabolic changes, including increased risk of diabetes

Controversies and Considerations

The use of AST is not without controversy, particularly concerning its timing and duration in the treatment of prostate cancer. Long-term androgen suppression can significantly impact a patient's quality of life and is associated with various health risks. As such, the decision to initiate AST should be made after careful consideration of the potential benefits and drawbacks, often involving a discussion about the patient's values, preferences, and overall health.

Conclusion

Androgen Suppression Therapy is a cornerstone in the management of prostate cancer, particularly in advanced stages of the disease. Despite its effectiveness, the potential side effects and impact on quality of life necessitate a personalized approach to treatment, balancing the benefits of cancer control with the risks associated with hormone suppression.