Correlation between Serum Testosterone and Tumor Grade in a Black African Population of Men with Prostate Cancer

BACKGROUND: In the past few decades, it was assumed that high testosterone levels were associated with increased risk of prostate cancer (CAP) while low testosterone was protective. However, more recent studies reported an association between low serum testosterone and high-grade CAP. These studies were largely done in the Western world, thus leaving a knowledge gap as regards such a relationship in Africans. Therefore, the aim of this study was to bridge this gap in knowledge by assessing the nature of the relationship between serum testosterone and tumor grade in a black African population of men with hormone naïve CAP. METHODS: This was a prospective study carried out in Enugu, Southeast Nigeria. The study population was drawn from men with histologically diagnosed CAP who subsequently had bilateral total orchidectomy (BTO) as a form of androgen deprivation therapy. Data were pulled from three referral centers for urological services in the city center with a study period extending from April 2022 to May 2025. Serum total testosterone and prostate-specific antigen (PSA) were assayed for each subject before undergoing BTO. RESULTS: A total of 147 subjects that met the inclusion criteria were included in this study. The mean age of the subjects was 70.2 ± 8.3 years, while the median Gleason score was 8.0 (IQR: 7.0-9.0). Majority of the subjects had Gleason scores of 7 (31.4%) or 9 (33.6%). The median PSA was 80.0 ng/ml (IQR: 40.0-103.0) while the median testosterone level was 3.7 ng/ml (IQR: 1.5-6.9). There was a very weak, statistically insignificant correlation between Gleason score and serum testosterone (r =-0.066, P = 0.442). CONCLUSION: The correlation between serum testosterone and tumor aggressiveness (as determined by Gleason score) is weak. Hence, by extrapolation, there may not be a need to include serum testosterone as part of preoperative workup investigations for CAP patients in our environment.