preview

Androgen Deprivation Therapy

Decent Essays

The key role of testosterone in the growth of prostate cancer was first demonstrated back in 1941 (Huggins, 1941); since then, androgen deprivation therapy (ADT) has provided the mainstay of treatment for patients with hormone-sensitive advanced prostate cancer. Although ADT is palliative, it can normalize serum levels of prostate specific antigen (PSA) in over 90% of patients and can produce objective tumour responses in 80-90%. This antitumor activity can improve quality of life (QOL) by reducing bone pain as well as the rates of complications (eg, pathologic fracture, spinal cord compression, ureteral obstruction). The duration of response to ADT for patients with metastatic disease is highly variable, and most prostate cancer patients eventually …show more content…

These agents bind to the GnRH receptor and initially trigger the secretion of LH, which in turn causes a surge in testosterone production lasting 1 to 2 weeks (Sasagawa, 1998; Tomera, 2001). This may stimulate prostate cancer cells, and in patients with advanced disease, exacerbate clinical symptoms such as skeletal pain, ureteral obstruction and spinal cord compression, which may lead to paralysis and, in rare cases, death (Thompson, 1990; Van Poppel, 2008a). The clinical effects of this “flare” can be limited by concomitant anti-androgen treatment (eg, flutamide or bicalutamide) (Perlmutter, 2009) to produce a combined androgen blockade. However, this strategy is not always effective and also associated with side effects. Chronic administration of GnRH receptor agonists eventually leads to suppression of LH, which results in a reduction of testosterone release (van Poppel, 2010).

The flare phenomenon associated with GnRH agonists helped to drive the search for alternative agents. Consequently, the new millennium saw the development of GnRH antagonists. These agents bind directly to and block GnRH receptors, without causing the initial testosterone surge and flare associated with agonists (Van Poppel, 2008a). Abarelix was the first GnRH antagonist to be licensed for prostate cancer treatment; however, this agent was associated with immediate-onset systemic allergic reactions resulting from histamine release and in 2005 was voluntarily withdrawn from US market (Huhtaniemi,

Get Access