High-grade prostate cancer is associated with low serum testosterone levels

The aim of this study was to assess whether low serum testosterone levels in men with newly diagnosed prostate cancer have an association to the endocrine status, prostate-specific antigen (PSA) levels, Gleason score, and androgen receptor expression.

Besides a full clinical work-up, the following hormones were quantified in men with newly diagnosed prostate cancer by serum analysis: total testosterone, human luteinising hormone (hLH), human follicle stimulating hormone (hFSH), estradiol, and dehydroepiandrostendione (DHEA). In a subgroup of men, androgen receptor expression was determined immunohistochemically.

One hundred and fifty six patients (65.7 +/- 8.5 yrs) with a mean PSA of 29.8 ng/ml (median: 7.4 ng/ml) were analysed. Fifty-two patients (33%) had a partial androgen deficiency (serum testosterone < 3.0 ng/ml). These men had lower hLH (3.3 vs. 5.9 mIU/ml), hFSH (6.2 vs. 8.4 mIU/ml), and estradiol (18.8 vs. 29.1 pg/ml) serum levels. Mean Gleason score was higher (7.4 vs. 6.2) in men with a low serum testosterone, PSA-levels were lower (25.3 vs. 31.9 ng/ml). Mean testosterone levels decreased from 4.1 +/- 1.7 ng/ml in patients with Gleason scores < or = 5 to 2.8 +/- 2.7 ng/ml with Gleason scores > or = 8. Androgen receptor expression was higher in patients with low serum testosterone.

Patients with high Gleason score prostate cancer have lower testosterone and estradiol serum levels. The fact that gonadotropins were lower in parallel suggests a tumor-mediated suppression of the hypothalamic-pituitary-gonadal hormone axis particularly in men with high Gleason score tumours.