The presence of one to four circulating tumor cells (CTCs) in the blood of early-stage breast cancer patients almost doubled patient’s risk of cancer relapse and death, and five or more CTCs increased recurrence by 400 percent and death by 300 percent, according to Phase III results of the SUCCESS trial. These cells were found in patients after surgery but before chemotherapy treatment. Results of this study were presented at the 33rd Annual CTRC-AACR San Antonio Breast Cancer Symposium, held Dec. 8-12, 2010, and demonstrate the value of CTCs in early breast cancer, independent of oestrogen-receptor or HER2 status and before use of adjuvant therapy.