#ASCO21: Large Cohort Study by Foundation Medicine and Collaborators Reveal Disparities in Precision Cancer Care

The pressing issue of equity in cancer care was a major point of discussion at this year’s ASCO meeting. Although cancer is a huge burden for all, some cancers disproportionately affect certain racial and ethnic populations more than others.

Prostate cancer is the fourth most commonly diagnosed cancer worldwide. Despite the recent decline in mortality rates, it is well documented that men of African ancestry are twice as likely to die of prostate cancer than men of European ancestry. This racial disparity is attributed to multiple factors, including systemic barriers that prevent access to genomic and precision medicine.

To throw more light into this issue, Cambridge-based Foundation Medicine and collaborators performed a large-scale study to evaluate biological and non-biological factors that might affect access to prostate cancer diagnosis and treatment to a population group.

They analyzed the genomic landscape, comprehensive genomic profiling (CGP) utilization, and treatment patterns in 11,741 patients, of which 12% (1,422) were men of African ancestry. As per their claims, this study encompassed the largest known cohort of its kind.

In addition, they also analyzed a small subset of 897 patients (79 men of African ancestry) with real-world clinical data from Foundation Medicine and Flatiron Health’s joint clinico-genomic database (CGDB).

Similar Rates of Actionable Gene Alterations Across Ancestry

Results showed that some genomic rearrangements occurred less frequently in men of African ancestry than their European counterparts. They include TP53 (35% vs. 43%), PTEN (21% vs. 33%), and TMPRSS2-ERG (15% vs. 33%). Conversely, some others occurred more frequently; SPOP (11.9% vs. 7.3%), CDK12 (10.0% vs. 5.2%), CCND1 (6.0% vs. 3.8%), KMT2D (7.7% vs. 5.1%), HGF (4.1% vs. 2.5%), and MYC (13.4% vs. 10.6%).

Overall men of both ancestries showed similar patterns of alteration frequency in BRCA1/2, AR, DNA damage response pathway genes, and actionable genes with therapeutic implications. Only BRAF alterations were slightly enriched in men of African ancestry (5.0% vs. 3.2%).

Disparities in Access to Early Genomic Testing and Clinical Trial Enrollment

Interestingly, the CGDB cohort analysis showed that men of African ancestry were less likely to receive clinical study drugs than men of European ancestry (11% vs. 30%), even among men with actionable alterations (1% vs. 6%). Notably, men of African ancestry were less likely to receive CGP earlier in their treatment course or be treated on clinical trials. These factors eventually impact the genomic landscape, outcomes, resulting in disparities.

“Men of African ancestry experience the greatest burden of disease in prostate cancer, and this research indicates that differences in cancer care are not solely based on biological factors, but rather points to socioeconomic factors such as access to comprehensive genomic profiling and clinical trial enrollment,” said study investigator Brandon Mahal, M.D., Assistant Professor, Sylvester Comprehensive Cancer Center.

“To ensure equitable opportunities for precision medicine, we need to expand access to and awareness of advances that impact patient care and outcomes, including timely use of genomic testing to help make informed treatment decisions.”

He acknowledged that the sample number is limited in this subset study and it warrants more follow-up to observe strong patterns.

Foundation Medicine was featured as one of GeneOnline’s 10 precision oncology companies to look out for.

Related Article: Day 4 ASCO 2021 Roundup: Immunotherapy Candidates Show Promise in Early Studies

Author

Rajaneesh K. Gopinath