A new study published in JAMA Oncology reveals that ancestry-based differences in biomarkers critical for selecting precision oncology treatments may contribute to disparities in cancer care outcomes.

Led by Kanika Arora of Memorial Sloan Kettering Cancer Center in New York City, the research analyzed data from 59,433 patients with solid cancers who underwent clinical sequencing through the MSK-IMPACT assay between 2014 and 2022. The study examined whether advancements in precision oncology drug approvals from 1998 to 2023 equally benefited patients from diverse ancestral backgrounds.

Findings showed that the approval of specific drugs, such as the EGFR-tyrosine kinase inhibitor erlotinib for EGFR-mutant lung cancer in 2013, had a disproportionate impact on certain populations. Patients of East Asian and South Asian ancestry were more likely to have level 1 biomarkers, which are essential for treatment with precision oncology drugs. Meanwhile, patients of African ancestry consistently exhibited the lowest fraction of level 1 biomarkers from 2019 onward, raising concerns about systemic disparities in clinical outcomes.

"These differences may exacerbate the systemic disparities in clinical outcomes in patients of African ancestry due to existing deficiencies in their access to cancer care," the authors noted.

Additionally, while an increase in precision oncology drug approvals during 2019 and 2020 positively impacted clinical actionability for patients of European ancestry, similar benefits were not observed for other populations.

Several authors of the study disclosed ties to pharmaceutical and biotechnology industries, underscoring the complexity of addressing disparities in cancer care.

The research highlights the urgent need for more inclusive clinical trials and equitable access to precision oncology to ensure that advancements in cancer treatment benefit all patients, regardless of their ancestry.