Non-Invasive Detection of Breast Cancer Metastasis
Posted Jan 31 2011 10:13am
Metastatic breast cancer involves the migration of breast cancer tumor cells to different sites in the body where they establish new tumors. This is an extremely serious complication of breast cancer that generally results in poor outcomes. While these breast cancer tumor cells can migrate to places like our bones, lungs, and brain, they frequently do this by first entering the lymph system and lymph nodes. For this reason, removal of one or more lymph nodes is frequently done to determine the stage of breast cancer and to determine whether it has become metastatic. This is an invasive, uncomfortable procedure that can result in unwanted side effects. New breast cancer research suggests that a non-invasive way to examine lymph nodes for their breast cancer involvement might become reality.
Breast cancer researchers recently reported that they have developed a new imaging probe by combining a specific antibody (MamAB-680) with a fluorescent dye. This new probe is designed to bind to a protein called mammaglobin-A. The study investigators showed that this mammaglobin-A protein is found of the surface of lymph node cells from breast cancer patients with lymph node involvement, but is not found on the surface of normal lymph nodes. This would suggest that this new imaging probe would only bind to lymph nodes in patients with lymph node positive breast cancer and therefore at risk for metastatic breast cancer. To test this, the researchers injected the new imaging probe into mice that either had or did not have this mammaglobin-A protein in breast tumors. Scanning the mice with a fluorescent imaging device showed that this new imaging probe was only found in positive tumors and metastasis. Furthermore, this imaging technique was shown to be very sensitive.
This is exciting research that might one day eliminate the need for sentinel lymph node biopsies . Breast cancer treatments depend upon the stage of the breast cancer, so accurately determining the stage of the breast cancer is important. Currently, this often includes surgical removal of one or more lymph nodes to determine whether the breast cancer has become metastatic. Any surgical procedure carries the risk of unwanted side effects, so minimizing the number of surgeries needed is highly desirable. Based on these animal studies, it appears that this new imaging probe can accurately determine lymph node involvement in breast cancer cases without the need for surgery. It will be exciting if these results can translate to human patients and eventually replace surgical lymph node removal.