Mayo Clinic Study Provides Critical Information on Tumor Sequencing and Chemotherapy in Breast Cancer

Tumor sequencing is increasingly used to select treatment for patients with cancer, but its role in women with newly diagnosed breast cancer is unknown. Mayo Clinic researchers reported on March 9, 2017, in the Journal of the National Cancer Institute (JNCI), the results of a prospective tumor sequencing study in women receiving chemotherapy prior to breast surgery. The article is titled “Tumor Sequencing and Patient-Derived Xenografts in the Neoadjuvant Treatment of Breast Cancer.” The goal was to determine whether tumor genomic alterations could differentiate patients with chemotherapy-sensitive and chemotherapy-resistant disease and to generate patient-derived xenografts (mouse avatars) to validate their findings. "There is great interest to use tumor sequencing data to guide therapy," says Matthew Goetz, M.D., Medical Oncologist and Co-Chair of the Breast Cancer Genome-Guided Therapy (BEAUTY) study. "However, there are limited data as to whether this approach is useful in women with newly diagnosed breast cancer who are recommended chemotherapy prior to breast surgery," he added. The main findings of the BEAUTY study, published in the JNCI, demonstrated that the most common genetic changes were not more commonly observed in chemotherapy-resistant compared to chemotherapy-sensitive tumors. However, Mayo investigators identified that an uncommon type of an aggressive breast cancer, the luminal androgen receptor subtype of triple-negative breast cancer (TNBC), was less likely to respond to chemotherapy, and was more likely to contain a unique type of mutation in p53, a tumor suppressor gene commonly mutated in TNBC.
Login Or Register To Read Full Story