Emulation of the SUNLIGHT Trial Using Specialty Oncology Electronic Health Records Databases

This observational study uses existing U.S. specialty oncology electronic health records to emulate the SUNLIGHT trial. It compares survival among adults with metastatic colorectal cancer who began trifluridine-tipiracil plus bevacizumab or trifluridine-tipiracil alone after prior systemic treatment. Treatment was chosen during routine care; the study did not assign treatment. The main outcome is time to death from any cause. Investigators will compare the real-world estimate with the published estimate from the randomized SUNLIGHT trial.

Inclusion Criteria: * Age 18 years or older at study regimen initiation. * Metastatic colorectal cancer documented in the oncology electronic health record. * Initiation of trifluridine-tipiracil (FTD-TPI) plus bevacizumab or FTD-TPI alone after two prior systemic treatment regimens for metastatic disease (third-line setting). * Known RAS mutation status at or before study regimen initiation. * Prior treatments included a fluoropyrimidine, irinotecan, and oxaliplatin. Prior anti-VEGF therapy was required for RAS-mutant disease; prior anti-VEGF or anti-EGFR therapy was required for RAS wild-type disease. * Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1 when ascertainable in the electronic health record. Exclusion Criteria: * Anticancer treatment in the four weeks before study regimen initiation. * Another primary malignancy in the five years before or on study regimen initiation, except adequately treated cervical carcinoma in situ or basal cell skin cancer. * Prior FTD-TPI use. * Other anticancer treatment during the treatment assessment window.