A method called molecular subtyping can help doctors better determine which of their breast cancer patients are at high risk of getting breast cancer again, a new study led by the University of South Florida reports. This sophisticated genetic profiling of an individual’s specific tumor offers an additional resource to help identify patients who would most benefit from chemotherapy and those who would not.
The findings by researchers from USF and other institutions were presented in a scientific poster at the Miami Breast Cancer Conference held last week.
“The most important takeaway for our colleagues in breast cancer diagnosis and treatment is the potential value of molecular subtyping to personalize and improve each woman’s treatment,” says principal investigator Charles E. Cox, MD.
Molecular subtyping is a way of classifying breast cancer tumors into one of four genetically-distinct categories, or subtypes: Luminal A, Luminal B, Basal (a subset of triple negative), and HER2-type. Each subtype responds differently to different kinds of treatments, and some indicate a higher risk of disease recurrence.
The study examined why different genomic tests for breast cancer sometimes provide contradictory information about risk of recurrence. Key findings involved the 70-gene MammaPrint test; the 21-gene Oncotype DX test, which is an earlier commercially available test; and Mammostrat, a gene profiling test performed on slides of the breast tumor by a pathologist. According to study authors, the tests have generally been assumed to provide equivalent information about recurrence risk, but that may not be the case. Learn more about the conference.