Elsevier

Urology

Volume 71, Issue 6, June 2008, Pages 1001-1006
Urology

Review Article
Testosterone Surge: Rationale for Gonadotropin-Releasing Hormone Blockers?

https://doi.org/10.1016/j.urology.2007.12.070Get rights and content

Gonadotropin-releasing hormone (GnRH) agonists currently form the mainstay of management of advanced prostate cancer. They effectively suppress serum testosterone levels, which in turn inhibits tumor growth. However, the initial response to GnRH agonists is a transient increase in the serum testosterone levels. Known as a testosterone surge, this can lead to a worsening of symptoms and can adversely affect survival. Therefore, much interest exists in the development of a new class of drugs—GnRH antagonists—which produce immediate suppression of luteinizing hormone and testosterone without a testosterone surge. The most promising GnRH antagonist to date is degarelix.

Section snippets

Characteristics of Testosterone Surge and Clinical Flare

The initial response to treatment with a GnRH agonist is a transient increase in the LH and testosterone levels. The LH levels can increase by up to 10-fold, and the testosterone levels can increase by approximately twofold. These increases are evident 2 to 3 days after the initial injection and can last up to 10 to 20 days from administration.8, 9 In turn, the increase in testosterone levels induces an increase in prostate-specific antigen, a marker of tumor growth (Fig. 3).10 Additional

Clinical Effect of Testosterone Surge

Accumulating evidence has suggested that, as well as inducing a worsening of clinical symptoms in many patients with metastatic disease, the testosterone surge associated with GnRH agonist therapy might also affect survival. As reviewed by Thompson et al.,15 sudden deaths during the flare associated with GnRH agonist therapy have been reported in seven series of patients. In these series involving approximately 300 patients (the exact number of patients involved was not given for three of the

GnRH Antagonists

GnRH antagonists are a new class of ADT that could have significant clinical benefits. These agents bind to the GnRH receptor in the pituitary to produce immediate blockade of LH and follicle-stimulating hormone secretion. This in turn results in fast suppression of serum testosterone levels, free of the testosterone surge and its clinical consequences (Fig. 2B). Thus, GnRH antagonists are, physiologically, a more logical approach to suppressing the growth of prostate cancer cells. A number of

Conclusions

ADT plays a key role in the treatment of patients with advanced or metastatic prostate cancer. Currently, GnRH agonists are the mainstay of management of metastatic disease and have been shown to achieve long-term suppression of serum testosterone levels. However, GnRH agonists induce an initial surge in testosterone, which results in worsening symptoms in approximately 10% of patients with metastatic disease. Of particular concern is the risk of ureteral obstruction and spinal cord

References (32)

  • D. McLeod et al.

    A phase 3, multicenter, open-label, randomized study of abarelix versus leuprolide acetate in men with prostate cancer

    Urology

    (2001)
  • D. Gonzalez-Barcena et al.

    Luteinizing hormone-releasing hormone antagonist cetrorelix as primary single therapy in patients with advanced prostatic cancer and paraplegia due to metastatic invasion of spinal cord

    Urology

    (1995)
  • C. Huggins et al.

    Studies on prostatic cancer: effect of castration, of estrogen and of androgen injection on serum phosphatases in metastatic carcinoma of the prostate

    Cancer Res

    (1941)
  • C. Labrie et al.

    Androgenic activity of dehydroepiandrosterone and androstenedione in the rat ventral prostate

    Endocrinology

    (1988)
  • D.A. Loblaw et al.

    American Society of Clinical Oncology recommendations for the initial hormonal management of androgen-sensitive metastatic, recurrent, or progressive prostate cancer

    J Clin Oncol

    (2004)
  • L. Boccon-Gibod et al.

    Management of locally advanced prostate cancer: a European consensus

    Int J Clin Pract

    (2003)
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    H. Van Poppel is an investigator in the degarelix clinical trials.

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