Clinical Trial Discussion and Participation in a Breast Cancer Cohort by Race and Ethnicity

Importance: Racial and ethnic disparities in breast cancer clinical trial participation pose a significant barrier to providing equitable care. Black and Hispanic patients are underrepresented in clinical trials, and an improved understanding of barriers to enrollment is needed.

Objective: To examine patterns of clinical trial discussion and participation and patient attitudes toward clinical trial participation in a diverse cohort of patients with breast cancer.

Design, Setting, and Participants: This cross-sectional study used survey data from patients enrolled in the Chicago Multiethnic Epidemiologic Breast Cancer Cohort. Patients were queried about clinical trial discussion and subsequent enrollment in a therapeutic clinical trial. Barriers to trial enrollment were also assessed. Surveys were conducted from July to September 2022, and data were analyzed from February to October 2024.

Exposure: Self-reported race and ethnicity, including Asian, Black, Hispanic, and White.

Main Outcomes and Measures: Outcomes of interest were discussing participation in a breast cancer clinical trial with a health care practitioner, participating in a clinical trial, and barriers to trial enrollment.

Results: Of 1150 respondents (mean [SD] age, 53.7 [11.9] years), 51 (4.4%) were Asian, 224 (19.5%) were Black, 35 (3.1%) were Hispanic, and 838 (73.0%) were White. A total of 447 respondents (38.9%) reported discussing trial participation with a health care practitioner. There were no differences in trial discussion between White patients and other racial groups (Asian: adjusted odds ratio [AOR], 0.75; 95% CI, 0.31-1.82; Black: AOR, 1.31; 95% CI, 0.78-2.21; Hispanic: AOR, 0.73; 95% CI, 0.26-2.08). Among 443 patients offered a trial, 285 (64.3%) participated. While there were differences in trial participation across racial and ethnic groups, these differences were not significant after adjusting for sociodemographic and clinical factors. Among 158 patients who did not enroll in the trial offered, 37 (23.4%) reported ineligibility, 17 (10.8%) were worried about the possibility of getting a placebo, 16 (10.1%) were worried about extra time required, and 14 (8.9%) were worried about possible adverse effects.

Conclusions and Relevance: This cross-sectional study demonstrated that when offered, patients across racial and ethnic groups were equally likely to participate in clinical trials. In addition to ineligibility, time toxicity was a significant barrier to enrollment. These data provide valuable insights that can serve as a roadmap for how to expand access to trials for all patients, regardless of racial, ethnic, and socioeconomic background.