Low levels of a protein that helps link cells together appears to be the single most effective factor for predicting which patients with early breast cancer will need chemotherapy following surgery, report researchers from the University of Chicago Medical Center in the January 15, 2000, issue of Cancer Research.
The researchers studying women with node-negative breast cancer, the small, early tumors sought by mammography found that by adding E-cadherin to other biomarkers that they have studied they are able to distinguish those patients with a 90 percent long-term survival from those whose survival is only 44 percent.
"We found that, for women with no affected lymph nodes, E-cadherin is the strongest prognostic factor for a poor long-term outcome," said first author Ruth Heimann, M.D., Ph.D., assistant professor of radiation and cellular oncology at the University of Chicago. "Our anaylsis suggests that biomarkers like E-cadherin are even more important than tumor size, tumor grade, the presence of estrogen receptors or the age of the patient."
It is not the original breast cancer that kills women but the tumor's spread to other sites. Surgeons can remove the initial tumor, radiation therapy is effective in treating disease that has reached nearby lymph nodes, and chemotherapy can decrease the risk of distant metastases. But chemotherapy is not always effective and has significant side effects. Only 20 to 30 percent of women with node-negative breast cancer will develop metastatic disease. If physicians could predict who was at risk they could increase the intensity of chemotherapy for those women and reduce or even eliminate the therapy and its side effects for those not at risk.
Unfortunately, the standard tools for assessing risk of metastasis such as the size of the tumor, its grade, the presence of estrogen receptors and the proportion of dividing cells are "insufficient," note the authors, "for clinical decision
Contact: John Easton
University of Chicago Medical Center