Among women with early breast cancer, the presence of circulating tumor cells (cancer cells in the bloodstream) increased the risk of cancer recurrence and shortened survival. These preliminary results were presented at the 2010 San Antonio Breast Cancer Symposium.
Among women with metastatic breast cancer (cancer that has spread to other sites in the body), detection of cancer cells in the bloodstream has been linked with shorter time to cancer progression and shorter survival. Less is known about the significance of circulating tumor cells in women with early-stage breast cancer.
To evaluate the impact of circulating tumor cells among women with early breast cancer, researchers evaluated more than 2,000 patients. The test to detect circulating tumor cells was performed after surgery and before the start of chemotherapy.
- Circulating tumor cells were detected in 21.5% of patients. Women with circulating tumor cells were more likely have node-positive breast cancer than women without circulating tumor cells.
- Compared with women with no circulating tumor cells, women with one to four circulating tumor cells were almost twice as likely to experience cancer recurrence and death.
- The presence of five or more circulating tumor cells was linked with a fourfold increase in recurrence risk and a threefold increase in risk of death.
These results suggest that detection of circulating tumor cells may provide information about recurrence risk and prognosis among women with early breast cancer. In a prepared statement, the lead researcher on the study noted, “Our study suggests testing [circulating tumor cells] may prove to be important to help individualize therapy for early-stage breast cancer…” Studies to further evaluate the role of circulating tumor cells are underway.
These results should be reviewed as preliminary by women with breast cancer and their doctors. Testing for circulating tumor cells is not indicated for women with early stage breast cancer. Other studies will have to be performed before this approach should be used in routine clinical practice.
Reference: Rack B, Schindlbeck C, Andergassen U et al. Prognostic relevance of circulating tumor cells in the peripheral blood of primary breast cancer patients. Presented at the 33rd annual San Antonio Breast Cancer Symposium, December 8-12, 2010. Abstract S6-5.