ASCO 2017: Serum androgens and survival in metastatic castration resistant prostate cancer patients treated with docetaxel and prednisone: Results from CALGB 90401 (Alliance)

Chicago, IL (UroToday.com) Higher baseline androgens have been previously shown to be associated with an improved overall survival (OS) in metastatic castration-resistant prostate cancer (mCRPC) patients treated with the androgen synthesis inhibitors, ketoconazole or abiraterone. This analysis was performed to determine whether baseline serum androgen levels Testosterone (Testo), Androstenedione (Andro) and DHEA are associated with OS in mCRPC patients treated with docetaxel-based chemotherapy. 

Dr. Charles Ryan presented data from 1,050 men from the CALGB 90401 trial including patients treated with docetaxel, prednisone, and either bevacizumab or placebo (Clinical trial information: NCT00110214). Eligibility required progressive mCRPC and no prior chemotherapy. Pre-treatment serum assays for Testo, Andro and DHEA were performed via tandem Liquid Chromatography-Mass Spectrometry (LC-MS/MS) at NMS labs. The proportional hazards model was used to assess the prognostic significance of Testo, Andro, and DHEA in predicting OS adjusting for known prognostic factors. 

Median values for Testo, Andro, and, DHEA were 1.00, 13.00 and 8.12, ng/dL respectively. Values below the median were defined as low and above as high. Median OS for low vs high levels was 22.7 and 23.1 months for Testo, 22.4 and 21.7 months for Andro and 21.8 and 24.0 months for DHEA, respectively, (all non-significant). In multivariable analysis adjusting for 10 known prognostic values and prior keto use in mCRPC, Andro (p-value = 0.013) levels were associated with OS. The HR for Andro was = 0.99 (95% CI = 0.98-0.99). 

In summary, multivariate analysis demonstrated that baseline androstenedione levels are prognostic factors for OS in mCRPC patients receiving chemotherapy. Low or undetectable levels of other androgens are associated with shorter OS, consistent with prior results in androgen synthesis inhibitor treated patients in both the chemotherapy naive and post chemotherapy settings. This relationship may reflect more aggressive tumor biology that evolves in an extreme androgen deprived milieu. 

Presented By: Charles J. Ryan, MD, University of California San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre
Twitter: @GoldbergHanan

at the 2017 ASCO Annual Meeting - June 2 - 6, 2017 - Chicago, Illinois, USA