Impact of clinical versus radiographic progression on clinical outcomes in metastatic castration-resistant prostate cancer

Arpit Rao, Howard I. Scher, Peter De Porre, Margaret K. Yu, Anil Londhe, Keqin Qi, Michael J. Morris, Charles Ryan

Research output: Contribution to journalArticlepeer-review

Abstract

Objectives Unequivocal clinical progression (UCP)-a worsening of clinical status with or without radiographic progression (RAD)-represents a distinct mode of disease progression in metastatic prostate cancer. We evaluated the prevalence, risk factors and the impact of UCP on survival outcomes. Methods A post-hoc analysis of the COU-AA-302, a randomised phase 3 study of abiraterone plus prednisone (AAP) versus prednisone was performed. Baseline characteristics were summarised. Cox proportional-hazards model and Kaplan-Meier method were used for survival and time to event analyses, respectively. Iterative multiple imputation method was used for correlation between clinicoradiographic progression-free survival (crPFS) and overall survival (OS). Results Of 736 patients with disease progression, 280 (38%) had UCP-only and 124 (17%) had UCP plus RAD. Prognostic index model high-risk group was associated with increased likelihood of UCP (p<0.0001). Median OS was 25.7 months in UCP-only and 33.0 months for RAD-only (HR 1.39; 95%CI 1.16 to 1.66; p=0.0003). UCP adversely impacted OS in both treatment groups. Lowest OS was seen in patients with prostate specific antigen (PSA)-non-response plus UCP-only progression (median OS 22.6 months (95%CI 20.7 to 24.4)). Including UCP events lowered estimates of treatment benefit-median crPFS was 13.3 months (95%CI 11.1 to 13.8) versus median rPFS of 16.5 months (95%CI 13.8 to 16.8) in AAP group. Finally, crPFS showed high correlation with OS (r=0.67; 95%CI 0.63 to 0.71). Conclusions UCP is a common and clinically relevant phenomenon in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with AAP or prednisone. UCP is prognostic and associated with inferior OS and post-progression survival. A combination of PSA-non-response and UCP identifies patients with poorest survival. When included in PFS analysis, UCP diminishes estimates of treatment benefit. Continued study of UCP in mCRPC is warranted.

Original languageEnglish (US)
Article numbere000943
JournalESMO Open
Volume5
Issue number6
DOIs
StatePublished - Nov 12 2020

Keywords

  • abiraterone
  • metastatic castration-resistant prostate cancer
  • no longer clinically benefiting (NLCB)
  • survival
  • unequivocal clinical progression

PubMed: MeSH publication types

  • Journal Article

Fingerprint Dive into the research topics of 'Impact of clinical versus radiographic progression on clinical outcomes in metastatic castration-resistant prostate cancer'. Together they form a unique fingerprint.

Cite this