Assessment of Patient and Clinician Perspectives on Clinically Meaningful Extension of Progression-free Survival in Prostate Cancer.

Background And Objective: It is widely accepted that the value of treatments for incurable metastatic cancer depends on their ability to improve overall survival (OS), quality of life (QoL), or both. Progression-free survival (PFS) is frequently used as a primary endpoint because of challenges in accurately assessing OS and QoL. The perceived value of extending PFS when there is uncertainty regarding the benefit to OS/QoL may vary between clinicians and patients.