Absence of Relationship Between Steroid Hormone Levels and Prostate Cancer Tumor Grade

Objectives: To analyze the relationship between plasma testosterone and estradiol levels on prostate biopsy and radical prostatectomy Gleason scores in a cohort of patients with newly diagnosed prostate cancer. Methods: Patients with prostate cancer evaluated at the Dana-Farber Cancer Institute from 2001 to 2005 who were enrolled in a prospective sample banking protocol were eligible for this study. Stored plasma was processed for total testosterone, total estradiol, and sex hormone-binding globulin levels using enzyme-linked immunosorbent assays. The frequency of high-grade biopsy and radical prostatectomy Gleason scores (>6) was the primary endpoint. Univariate and multivariate logistic regression analyses were performed to determine the relationship between the hormone levels and high-grade Gleason scores while adjusting for sex hormone-binding globulin, age, body mass index, and prostate-specific antigen. Results: A total of 539 patients were included in this study, 199 of whom underwent radical prostatectomy. The median prostate-specific antigen level was 5.1 ng/dL, and 67% of the cancers were not palpable. The Gleason score was 2-6, 7, and 8-10 in 53%, 37%, and 10% of the cancers, respectively. On univariate analysis of the high-grade biopsy and radical prostatectomy Gleason score, the total testosterone, total estradiol, and estradiol-to-testosterone ratio were not significant as continuous or categorical variables. Adjusting these results for sex hormone-binding globulin level, body mass index, age, and prostate-specific antigen level did not change the conclusions, and these results were unchanged when categorizing high-grade prostate cancer as Gleason score 8-10. Conclusions: No relationship was found between the circulating steroid hormone levels and the Gleason score in this cohort.