Circulating Tumor Cells Help Treatment

Counting circulating tumor cells before and after the start of treatment for patients with metastatic colorectal cancer could help treatment, says a U.S. study.

Study leader Neal J. Meropol, director of the gastrointestinal cancer program at Philadelphia’s Fox Chase Cancer Center, and colleagues examined the association between the circulating tumor cell number and progression-free and overall survival for 430 adult patients with metastatic colorectal cancer.

The number of circulating tumor cells was measured at baseline, one month and several other points after the start of treatment. Circulating tumor cells were isolated and counted.

Having three or more circulating tumor cells per 7.5 mL of blood was defined as unfavorable in an initial analysis, while patients with fewer than three circulating tumor cells were considered favorable.

Patients with unfavorable circulating tumor cells had a shorter median survival time, Meropol said in a statement. This was even seen in those patients whose CT scan — the gold standard for tumor evaluation — indicated no disease progression.

The findings were presented at the annual meeting of the American Society of Clinical Oncology in Chicago.