Factors associated with clinical trial participation for patients with renal cell carcinoma

Recruitment of a diverse and representative study population is critical to the external validity of oncology clinical trials. The primary objective of this study was to characterize the factors associated with clinical trial participation for patients with renal cell carcinoma and the secondary objective was to examine differences in survival outcomes.

We used a matched case-control design by querying the National Cancer Database for patients with renal cell carcinoma who were coded as having enrolled in a clinical trial. Trial patients were matched in a 1:5 ratio to the control cohort based on clinical stage and then sociodemographic variables were compared between the 2 groups. Multivariable conditional logistic regression models evaluated factors associated with clinical trial participation. The trial patient cohort was then matched again in a 1:10 ratio based on age, clinical stage, and comorbidities. Log-rank test was used to compare overall survival (OS) between these groups.

From 2004 to 2014, 681 patients enrolled in clinical trials were identified. Clinical trial patients were significantly younger and had a lower Charlson-Deyo comorbidity score. On multivariate analysis, male patients and white patients were more likely to participate compared to their Black counterparts. Having Medicaid or Medicare negatively associated with trial participation. Median OS was greater among clinical trial participants.

Patient sociodemographic factors remain significantly associated with clinical trial participation and trial participants experienced superior OS to their matched counterparts.