RxPONDER: SABCS 2022 Yara Abdou Racial Disparities SWOG S1007
The focus was on patient-reported anxiety and fatigue in women, what were the findings? Our study was focused on determining whether there were racial or ethnic disparities in patient outcomes in the RxPONDER trial.
As a reminder, the RxPONDER trial is what established the clinical utility of the 21-gene recurrence score in participants with hormone positive HER2 negative breast cancer and 1–3 positive lymph nodes.
Our study objectives were to evaluate the entire cohort for clinical and pathologic characteristics by race, analyze the clinical outcomes by race, and determine whether race is predictive of treatment benefit in early hormone positive breast cancer. The study included 4,048 women from the RxPONDER trial with known race and ethnicity.
In regards to clinical characteristics, there were no significant differences in tumor size, lymph node involvement, or the 21-gene (expression) recurrence scores by race. However, there were more high grade tumors among the non-Hispanic Blacks compared to the non-Hispanic Whites, and in regards to outcomes, the non-Hispanic Black cohort had an inferior 5 years invasive disease-free survival rate of 87.2% compared to 91.5% in the non-Hispanic White cohort.
On the other hand, Asian patients had a superior invasive disease-free survival compared to non-Hispanic whites and other racial cohorts.
Additionally, the non-Hispanic Black patients were noted to have lower distant, relapsed pre-survival compared to non-Hispanic Whites and other races. Adjusting for recurrent score treatment, arm menopausal status, age group, and grade in a multi-variable analysis did not alter the impact of race, adjusting that independently prognostic in this cohort of patients.
In terms of treatment effect, there was no significant interaction between race and treatment arm in either the postmenopausal or premenopausal cohorts.
However, I would like to note that there were a very small number of events in the non-Hispanic Black cohort. Therefore, this was a limited analysis, and definitive conclusions about racial differences in treatment benefit cannot be made at this time.
What are the most common questions you’re asked by your colleagues about the RxPONDER study?
One of the most common questions asked by several of our colleagues was whether endocrine therapy compliance was a factor contributing to inferior outcomes noted in the Black population. Our analysis showed that in terms of treatment compliance, non-Hispanic Blacks were more likely to accept their treatment assignment compared to non-Hispanic Whites at the time of randomization.
And were just as likely to remain on endocrine therapy at that 6 and 12 month interval after randomization, suggesting that the outcome differences are less likely attributable to lack of treatment compliance within that first year. However, data beyond the first year it’s still immature. Therefore, I think we need further analysis and longer follow up to confirm this finding.
Another common question was whether the outcome differences noted were related to breast cancer events and not some other comorbidities. Since invasive disease-free survival as an outcome includes non-breast cancer related events, and based on our invasive disease-free survival event analysis, the majority of the events in the non-Hispanic black cohort were related to breast cancer recurrence, whether local, regional, or distance. Therefore, the hazard ratio did not seem to be driven by non-breast cancer related events.
Read and Share the Article Here: https://oncologytube.com/v/41576
Listen and Share the Audio Podcast Here:
Will this data from the RxPONDER trial affect clinicians today?
At this time, there is no compelling evidence to suggest that race has an effect on treatment benefit. Therefore, the overall results of RxPONDER, which showed that postmenopausal woman with positive nodes and a recurrent score of 25 or less may safely avoid adjuvant chemotherapy as of now should be considered true for all races and ethnicities.
This prospective clinical trial was built in racial cohorts are needed to answer such questions definitively in the future.
What is the next step for this research in hormone positive HER2 negative breast cancer?
Next steps for us will include investigating possible underlying causes for the disparities we noted. In RxPONDER. We will be looking at biological factors, including differences in tumor biology, particularly the proliferation gene (expression) group, differences by race. We will also be looking at non-biological factors, including social determinants of health based on geographic location to determine whether these were contributing to the disparities noted as well.
We also plan to assess the likelihood of treatment completion and adherence by race and ethnicity beyond that first year.
What are the key takeaways from this research and data on the RxPONDER clinical trial?
Our study results similar to prior studies indicate racial disparities in breast cancer, particularly in the hormone positive breast cancer subtypes. This highlights that clinicians need to put more effort into ways to improve outcomes for Black women with breast cancer, starting with greater representation of racial and ethnic minorities in our clinical trials and research studies to help further understand cancer disparities and ultimately improve outcomes for minority women with breast cancer.
What are your final thoughts?
I would like to emphasize the importance of diversity and inclusion in clinical trials under representation of certain groups in a study can make the results less applicable to groups who may benefit from the findings the most. And one way we can, we as clinicians can improve inclusion in our trials is to carefully consider the eligibility criteria for enrollment on trials to avoid discriminating against certain populations, other ways we can in ensure diversity, to increase our cultural awareness and involve our patient advocates in the design of the trials, which will help recruit and retain minority woman with breast cancer in our trials.
Yara Abdou, MD – About The Author, Credentials, and Affiliations
She is a medical oncologist at the UNC Lineberger Comprehensive Cancer Center, Yara Abdou, MD, specializes in the treatment of early-stage and advanced breast cancer. Her research focuses on the creation of innovative medicines, notably immunotherapy, to treat various breast cancer subtypes. She collaborates closely with fundamental and translational scientists to investigate the microenvironment of breast tumors and develop strategies to improve immune-based therapeutic options.
In addition, her research focuses on racial differences in tumor biology and the immune microenvironment in an effort to better comprehend racial disparities and improve clinical outcomes for minority women with breast cancer. As a clinician and researcher, her objective is to develop breast cancer treatment options while minimizing disease-related suffering and morbidity.