Measuring the change in circulating tumour cell (CTC) count can accurately predict the prognosis and survival in patients with metastatic breast cancer (MBC), according to a newly published report in the July 10 issue of the Journal of Clinical Oncology.

The retrospective study compared how well CTCs and a more sensitive than conventional modality, fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT), predicted survival in MBC patients on standard therapies. The comparison showed that both technologies significantly correlate to overall MBC patient survival (p<0.001 for CTCs and p=0.001 for FDG-PET/CT). However, a CTC count of five or more could better predict the prognosis and survival in MBC patients.

The CellSearch System is the first 510(k) diagnostic test used to automate the capture and detection of CTCs, tumour cells that have detached from solid tumours and entered the patient's blood.

"Measuring CTCs in metastatic breast cancer patients provides oncologists with an additional tool to help us better monitor patient outcomes," said one of the lead authors, Dr Massimo Cristofanilli, associate professor in the Department of Breast Medical Oncology at The University of Texas, Maryland Anderson Cancer Center. "The CellSearch CTC test provides an early indication about patients' disease progression and overall survival."

CTCs and FDG-PET/CT are two of the most promising new tools for therapeutic monitoring in patients with MBC. The number of CTCs identified in patients with MBC is related to patient prognosis; a high number of CTCs at any time during treatment is associated with poor prognosis.

"Veridex is committed to providing oncologists with high-value in vitro diagnostic solutions, such as the CellSearch CTC test, to help them make informed patient care decisions," said Ken Berlin, general manager of Veridex. "This study demonstrates the utility of integrating the CellSearch CTC test in therapeutic monitoring of patients with metastatic disease."

The CellSearch test works by using antibodies that are joined to microscopic iron particles, called ferrofluid. These antibody/ferrofluid combinations attach very specifically to CTCs.

Veridex, LLC, a Johnson & Johnson company, is an organization dedicated to providing physicians with high-value in vitro diagnostic oncology products.