Sentinel node mapping is a valuable tool.
Mapping helps doctors to determine if the patient's cancer has spread to the lymph nodes.
But it must be done before a lumpectomy is performed. Wendy Chioji Rene McLemore knows that kind of pain. It was nine years ago that McLemore's left breast and most of her lymph nodes were removed because of breast cancer. Last month, cancer was found in McLemore's right breast, but this time only a couple of her lymph nodes were removed thanks to sentinel node biopsy. To find out if breast cancer has spread, a surgeon injects a mildly radioactive liquid and a blue dye into the area near the tumor.