Study shows utility of cfDNA blood tests for breast cancer patients

Researchers from Chronix Biomedical and The University of Texas MD Anderson Cancer Center today announced that results from a pilot study demonstrating the utility of cell-free DNA (cfDNA) blood tests as a companion diagnostic for breast cancer patients are to be reported in a poster presentation titled "Modulation of breast cancer cell-free DNA with surgical resection" (Abstract #11060) at the American Society of Clinical Oncology Annual Meeting (ASCO 2013) being held from May 31 through June 4, 2013 in Chicago. The blood test detects cfDNA that is released into the blood stream by damaged and dying cancer cells.

“This study is exciting and has the potential to greatly improve the outcome for breast cancer patients. We expect to be able to transition the approach to many other tumor lineages. Thus the proposed study should have a major impact on cancer patient management and outcomes”

In the study, researchers applied advanced next-generation sequencing (NGS) techniques to identify tumor-associated cfDNA in 16 breast cancer patients undergoing surgical excision of their primary breast cancer. Analysis of pre- and post-surgery serum demonstrated that cfDNA cancer biomarkers were present in the pre-surgery serum and in the original tumor biopsy, and were not observed in white blood cell (WBC) genomic DNA. In 13 of 16 patients (81%) analyzed, the post-surgery cfDNA was free of detectable tumor-related DNA. In the remaining 3 patients only a partial reduction in tumor-specific DNA serum biomarkers was detected, since some markers were still detectable after surgery. This preliminary finding is the basis for a larger planned study designed to determine if residual tumor cfDNA after surgery is a marker of minimal residual disease, which can be pursued as a prognostic marker.

In addition, the researchers expect to expand this study to a larger cohort of women undergoing neoadjuvant therapy (NAT) involving several rounds of chemotherapy, typically followed by surgery to remove the tumor in an effort to increase the probability of achieving "complete" elimination of cancer cells. A major problem is that a high percentage of patients undergoing NAT have a complete pathological response to the chemotherapy with eradication of all tumor in the breast and lymph nodes. However, as there is currently no accurate way to identify patients who had a complete response surgery is routinely performed on all patients after NAT. A biomarker companion diagnostic blood test for the real-time monitoring of cancer would enable the physician to determine whether cancer actually remains in the body post-therapy.

"If we are successful in further validating this innovative research, a major advance will be made toward providing a new era of personalized medicine," said Professor Funda Meric-Bernstam, M.D., Chair, Department of Investigational Cancer Therapeutics, and Medical Director, Institute of Personalized Cancer Therapy, MD Anderson, and Principal Investigator of the study.

"This study is exciting and has the potential to greatly improve the outcome for breast cancer patients. We expect to be able to transition the approach to many other tumor lineages. Thus the proposed study should have a major impact on cancer patient management and outcomes," said Professor Gordon Mills, M.D., Chair of Systems Biology at MD Anderson.

"These positive data provide the basis for the continued development of minimal residual disease blood tests for as many cancer types as possible. These tests have the potential to track responses to any oncology treatment, and are expected to significantly enhance patient care while greatly reducing the cost to the healthcare system," said Howard Urnovitz, Ph.D., Chief Executive Officer of Chronix Biomedical.

Source: Chronix Biomedical