Riscos cardiovasculares do bloqueio androgênico

Abstract

increasing in the last years, a fact attributed mainly to the routine measurement of the prostate-specific antigen (PSA) in males aged 45 years and older. This type of cancer presents the highest correlation with age and it is believed, in the USA, that one in every six men will be diagnosed with prostate cancer in his lifetime 3 . In spite of the high incidence, the mortality rates are relatively low, with a projected number of deaths of little more than 27,000 in the USA in the year 2007, corresponding to 9% of the total number of cancer-related deaths. Approximately 86% of the diagnoses are attained when the disease is still localized and the disease-free five-year survival rate is close to 100% 4 . Prostate cancer treatment: attention to androgen deprivationRegarding the treatment, prostate cancer presents several therapeutic possibilities, such as radiotherapy/brachytherapy, prostatectomy, androgen deprivation therapy and even an expectant conduct in special situations, depending on the clinical stage of the disease, tumor aggressiveness assessment, the presence of comorbidities and the patient's life expectancy. Androgen deprivation therapy was first used by Huggins and Hodges in 19415 . Its effect is based on the fact that the prostatic neoplastic cells present a large number of androgen receptors on their surface and that their growth depends on the stimulation of these receptors. In brief, we can affirm that testosterone is the main circulating androgen and most of it is produced by Leydig cells in the testes, after central stimulation by the gonadotropin-releasing hormone (GnRH) and the luteinizing hormone (LH), which are secreted by the hypothalamus and the pituitary, respectively. After entering the prostate, testosterone is converted by 5α-reductase into dihydrotestosterone and binds to a cytoplasmic receptor, forming a complex that modulates the nuclear transcription and consequently, all cell activity 6 . The figure below illustrates this hormonal axis and the specific mediations used to block it (Figure 1).The androgen deprivation can be attained through GnRH agonists, steroidal and nonsteroidal antiandrogens, estrogens or bilateral orchiectomy. This review will cover only GnRH agonists and orchiectomy, the modalities considered to be the most efficient ones. GnRH agonists such as leuprolide and goserelin result in a central deprivation of testosterone secretion by suppressing the physiological pulsatility of GnRH secretion, with a consequent negative regulation of the pituitary receptors and lower LH secretion. These are long-acting medications administered by depot-injections. The orchiectomy is another form to inhibit androgen activity AbstractProstate adenocarcinoma is the most common cancer type in the male sex after skin cancer. Among the several types of treatment for prostate cancer, the androgen deprivation therapy has been highly recommended in patients with metastatic or locally advanced disease, which probably results in increased survival. However, the androgen deprivation is the cau...

Cardiovascular Disease Risk Factors: How Relevant in African Men With Prostate Cancer Receiving Androgen-Deprivation Therapy?

“…Androgen deprivation is achieved using gonadotropin-releasing hormone (GnRH) agonists, steroidal and nonsteroidal antiandrogens, estrogens, or bilateral orchiectomy. 8 The aim of ADT is to reduce serum testosterone levels to less than 0.5 mg/L as recommended by current guidelines. The normal range for testosterone in young men is 3 to 10 mg/L.…”