June 1, 2024
By Catlin Nalley
A retrospective analysis of advanced endometrial cancer patients revealed racial/ethnic inequities in treatment initiation, biomarker testing, and clinical trial participation. This data, which was recently presented during the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting, suggests that clinical trial inequities were partly explained by structural racism and social determinants of health (SDOH) factors, according to the study authors (Abstract 1602).
"Racial/ethnic inequities in endometrial cancer care and outcomes are well-documented," noted study author Cleo A. Ryals, PhD, and colleagues. "Structural racism and social determinants of health have been linked to inequities in cancer care and outcomes."
“However, little is known about the contribution of such factors to care inequities among patients with endometrial cancer, where Black women experience a nearly two-fold increased risk of death relative to their White counterparts,” they explained. “We examined the role of structural racism and social determinants of health in explaining racial/ethnic inequities in care for patients with advanced endometrial cancer.”
In this retrospective study, the research used the U.S. nationwide Flatiron Health electronic health record (EHR)-derived de-identified database, which is comprised of patient-level structed and unstructured data, originating from approximately 280 cancer clinics.
Study participants included patients diagnosed with advanced endometrial cancer from January 2013 to December 2023 with at least two documented clinical visits on different days. Patients were followed until outcome of interest, end of the patient’s record, death, or until Dec. 31, 2023.
The key outcomes of this analysis were time-to-treatment initiation, use of immunotherapy or targeted therapy, biomarker testing, and clinical trial participation. Researchers categorized EHR-documented race and ethnicity into the following mutually exclusive groups: Non-Latinx (NL)-Asian, NL-Black, Latinx, NL-White, and other/not documented (includes all other racial groups due to small sample size).
Residential segregation was used to capture structural racism. The social determinants of health factors included practice setting (community/academic), geography (rural/urban), residence in a medically underserved area, and area-level factors from the American Community Survey (vehicle ownership, English proficiency).>
“We estimated a series of multivariable Cox proportional hazards models assessing racial/ethnic inequities in outcomes, sequentially adjusting for clinical factors (e.g., age, stage at diagnosis) followed by structural racism (residential segregation) and social determinants of health factors (e.g., insurance, practice setting, area-level vehicle ownership),” Ryals and colleagues outlined.
This cohort included 5,496 patients (2.2% NL-Asian, 14.8% NL-Black, 5.3% Latinx, 61.7% NL-White, and 16% Other/Unknown). Overall, the median age of study participants was 67 years old and the majority were in the community practice setting (70%). Histology for the entire patient cohort was as follows: carcinosarcoma/MMT (9.9%), clear cell carcinoma (4.1%), endometrial cancer NOS (9.4%), endometroid carcinoma (54%), and serous carcinoma (23%).
While data showed that Black patients were diagnosed with more aggressive disease (37% vs. 21% serous carcinoma), they were less likely than their White counterparts to initiate treatment during follow-up (HR=0.91, 95% CI: 0.83-0.99), participate in a clinical trial (HR=0.56, 95% CI: 0.38-0.84), and receive biomarker testing (HR=0.88, 95% CI: 0.81-0.97).
When compared to White patients, the study authors found that Latinx patients were less likely to participate in a clinical trial (HR=0.41, 95% CI: 0.19-0.87). Additionally, they reported that “Black-White (HR=0.80, 95% CI: 0.47-1.38) and Latinx-White (HR=0.71, 95% CI: 0.31-1.60) inequities in clinical trial participation were partly explained by structural racism and SDOH factors, while Black-White inequities in treatment and biomarker testing remained largely unchanged following structural and social determinants adjustment.”
The investigators reported no racial/ethnic differences in the use of immunotherapy or targeted therapy.
"We observed racial/ethnic inequities in treatment initiation, biomarker testing, and clinical trial participation among patients with advanced endometrial cancer, with structural racism and SDOH substantially accounting for inequities in trial participation,”" Ryals and colleagues stated.
"Thus, findings from this study suggest that efforts aimed at improving diversity in endometrial cancer trials, and overall equity in endometrial cancer outcomes, should prioritize mitigating the structural and social barriers to clinical trial participation," they concluded.
Catlin Nalley is a contributing writer.