Presentation Authors: Maxwell Towe, Linda M Huynh, Farouk M El-Khatib, Faysal A Yafi, Thomas Ahlering*, Orange, CA
Introduction: The role of testosterone on prostate growth and its relationship with prostate cancer development is a controversial topic. Most current data claim that low levels of testosterone may be a risk factor for higher grade cancer. The present study seeks to assess the role of total (TT) and free testosterone (FT) in disease progression post-radical prostatectomy.
Methods: From December 2009 to June 2018, 800 patients underwent robot-assisted radical prostatectomy (RARP) for primary treatment of localized prostate cancer by a single surgeon. Pre-operative and 3 month post-operative TT and FT were prospectively collected and calculated, along with prostate specific antigen (PSA), pathological stage, and pathological grade. Patients were included for analysis if all of the above values were available.Primary and secondary outcomes were biochemical recurrence (BCR) (defined as 2 consecutive PSA values of 0.2 ng/dL or greater) and time to BCR, respectively. Median follow-up was 2.75 years post-RARP. Student t-tests were used to compare means of preoperative and 3 month TT and FT for patients who experienced BCR vs. those who did not. Multivariate analyses was performed to assess for influence of age, pathological grade, pathological stage, TT (pre-op and at 3 mos), and FT (pre-op and at 3 mos).
Results: Overall, 143/687 (20.8%) patients experienced BCR. Pre-operative FT (BCR: 5.4Â±2.31, no BCR: 6.18Â±3.48), 3 month FT (BCR: 6.08Â±2.74, no BCR: 7.14Â±3.83) and 3 month TT (BCR: 367Â±179.78, no BCR: 402Â±194.45) were significantly lower in BCR patients (p = 0.004), (p = 0.002), (p = 0.048), respectively. After adjusting for age and pathological grade, a lower 3 month FT independently predicted time to BCR (p=0.038) along with pathologic stage (p=0.001
Conclusions: Low levels of FT may hasten time to BCR post-RARP. Men with low TT and FT may benefit from an oncologic standpoint with normalization of these values, possibly through testosterone replacement therapy. These results confirm that higher FT does not further the progression of prostate cancer.