Description:
A cancer cell that breaks away from the original (primary) tumor and enters the bloodstream. Circulating tumor cells can travel through the blood and form new tumors in other parts of the body. A sample of blood can be used to detect circulating tumor cells and learn more about the primary tumor. Circulating tumor cells are being used as a biomarker in some types of cancer to help plan treatment or make a likely prognosis. Also called CTC.
