The relationship between pre-radiation therapy testosterone levels and prostate cancer aggressiveness

Abstract

We investigated whether there is an association between testosterone levels and prostate cancer aggressiveness in patients treated with radiation therapy who underwent a prostatectomy or prostate radiotherapy (EBRT). A total of 380 patients who received primary or post-operative radiotherapy were identified. At the time of radiotherapy, baseline testosterone levels and body mass index (BMI) measurements were available. On multivariate analysis (MVA), higher prostate-specific antigen (PSA) levels were predictive of testosterone ≥10.4 (OR = 1.3, p = .04) and testosterone ≥12.0 nmol/L (OR = 1.3, p = .04). Patients with a Gleason score ≥8 were more likely to have testosterone <8 nmol/L than patients with a lower score (31% vs. 20%, p = .043). On univariate analysis, a Gleason score ≥8 was associated with a lower likelihood of having a normal (≥8 nmol/L) testosterone level (OR = 0.51, 95% CI: 0.3-0.9, p = .02), and on MVA adjusted for post-surgical versus primary EBRT and BMI (≥30 kg/m² ), the Gleason score lost its statistical significance (p = .09). While higher PSA levels are associated with higher testosterone levels, the interaction between Gleason score and testosterone is unclear and merits further study.

Keywords: Gleason; PSA; prostate cancer; testosterone.