Prospective multicenter study of circulating tumor cell AR-V7 and taxane versus hormonal treatment outcomes in metastatic castration-resistant prostate cancer Journal Article


Authors: Armstrong, A. J.; Luo, J.; Nanus, D. M.; Giannakakou, P.; Szmulewitz, R. Z.; Danila, D. C.; Healy, P.; Anand, M.; Berry, W. R.; Zhang, T.; Harrison, M. R.; Lu, C.; Chen, Y.; Galletti, G.; Schonhoft, J. D.; Scher, H. I.; Wenstrup, R.; Tagawa, S. T.; Antonarakis, E. S.; George, D. J.; Halabi, S.
Article Title: Prospective multicenter study of circulating tumor cell AR-V7 and taxane versus hormonal treatment outcomes in metastatic castration-resistant prostate cancer
Abstract: PURPOSE Androgen receptor splice variant 7 (AR-V7) detection in circulating tumor cells (CTCs) is associated with a low probability of response and short progression-free (PFS) and overall survival (OS) in men with metastatic castration-resistant prostate cancer (mCRPC) treated with enzalutamide or abiraterone. However, it is unclear whether such men benefit from taxane chemotherapy. PATIENTS AND METHODS PROPHECY is a multicenter prospective blinded study of patients with poor-risk mCRPC starting abiraterone or enzalutamide and observed through subsequent progression and taxane chemotherapy. We assessed AR-V7 status using the Johns Hopkins modified AdnaTest CTC AR-V7 messenger RNA assay and the Epic Sciences CTC nuclear-localized AR-V7 protein assay before treatment. The primary objective was to validate the independent prognostic value of CTC AR-V7 status based on radiographic/clinical PFS. OS, confirmed prostate-specific antigen (PSA), and objective radiologic responses were secondary end points. RESULTS We enrolled 118 men with mCRPC treated with abiraterone or enzalutamide, 51 of whom received subsequent docetaxel or cabazitaxel. Pretreatment CTC AR-V7 status by the Johns Hopkins and Epic Sciences assays was independently associated with worse PFS (hazard ratio [HR], 1.7; 95% CI, 1.0 to 2.9 and HR, 2.1; 95% CI, 1.0 to 4.4, respectively) and OS (HR, 3.3; 95% CI, 1.7 to 6.3 and HR, 3.0; 95% CI, 1.4 to 6.3, respectively) and a low probability of confirmed PSA responses, ranging from 0% to 11%, during treatment with abiraterone or enzalutamide. At progression, subsequent CTC AR-V7 detection was not associated with an inferior PSA or radiographic response or worse PFS or OS with subsequent taxane chemotherapy after adjusting for CellSearch CTC enumeration and clinical prognostic factors. CONCLUSION Detection of AR-V7 in CTCs by two different blood-based assays is independently associated with shorter PFS and OS with abiraterone or enzalutamide, but such men with AR-V7–positive disease still experience clinical benefits from taxane chemotherapy. © 2020 by American Society of Clinical Oncology.
Journal Title: JCO Precision Oncology
Volume: 4
ISSN: 2473-4284
Publisher: American Society of Clinical Oncology  
Date Published: 2020-10-28
Start Page: 1285
End Page: 1301
Language: English
DOI: 10.1200/po.20.00200
PROVIDER: scopus
PMCID: PMC7608579
PUBMED: 33154984
DOI/URL:
Notes: Article -- Export Date: 1 December 2020 -- Source: Scopus
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  1. Howard Scher
    1130 Scher
  2. Daniel C Danila
    155 Danila