Researchers at Georgetown Lombardi Comprehensive Cancer Center have suggested that the number of circulating tumor cells (CTCs) in the blood is a "powerful predictor" to help physicians more reliably assess treatment benefits for patients with metastatic breast cancer.
Minetta Liu, lead investigator of the new analysis and director of translational breast cancer research at Georgetown Lombardi says the new analysis substantiates the utility of the CTC test, which counts the number of CTCs in the blood.
CTC results at or above the threshold of five are reliably associated with clinical and/or radiographic evidence of worsening disease, strengthening considerations for a change in therapy with the goal of improving long-term patient outcomes.
Teams from cancer centers around the world contributed blinded data to create a pooled dataset of 841 patients. This large sample size enabled Liu to confirm findings from other studies that indicate a CTC count of five or more is associated with disease progression.
Importantly, the predictive value of CTCs was not affected by treatment type (chemotherapy, endocrine therapy, biologic therapy), tumor type (hormone receptor positive/negative, HER2 positive/negative), or sites of disease involvement.
"Using a blood test to count CTCs in addition to our existing tools for disease monitoring might improve our ability to appropriately treat patients and maximize their quality of life," said Liu.
The findings will be presented at the 2011 annual meeting of the American Society of Clinical Oncology in Chicago.