LAUSR

Key Points Question What surrogate end point for capturing worsening disease is most correlated with overall survival (OS) in large linked clinicogenomic data sets? Findings In this cohort study of patients with non–small cell lung cancer or colorectal cancer who initiated systemic therapy for advanced disease, progression-free survival based on both radiologist and medical oncologist assessment was more consistently correlated with OS than other candidate end points, including time to treatment discontinuation and time to next treatment. Meaning This study suggests that, based on its correlation with OS, progression-free survival based on both radiologist and medical oncologist assessment may be an optimal surrogate end point for analysis of observational clinicogenomic data in cancer research.