Published on August 23, 2005 at 7:48 AM
In an average of 36 months of post-treatment follow-up, none of the patients showed progression of cancer in the lymph nodes. The sentinel node biopsy accurately predicted node involvement, with a false negative rate of 0 percent, Ollila said.
Some surgeons advocate performing sentinel node biopsy in women with large tumors only after chemotherapy to discover how much of the tumor is left behind. However, these results show that performing the procedure before treatment provides a more accurate picture of lymph node involvement, Ollila said.
"If sentinel node biopsy is done after chemotherapy, the false negative rate skyrockets," he said.
Published studies show false negative rates as high as 33 percent when the procedure is performed only after chemotherapy. False negatives may result, for example, when chemotherapy kills cancer cells in the sentinel node but not in other nodes.
"We're looking at a way in which the patient has definitive breast cancer and nodal staging before she ever undergoes chemotherapy, so we know exactly where she starts," Ollila said. "Performing this procedure before neoadjuvant chemotherapy makes it easier for the medical oncologist and the radiation oncologist to know exactly what they need to do."
Other authors of the study are UNC Lineberger and medical school faculty members Drs. Carolyn Sartor, assistant professor of radiation oncology; Lisa A. Carey, assistant professor of medicine; and Nancy Klauber-DeMore, assistant professor of surgery. Dr. Heather B. Neuman, a resident in the department of surgery, also is co-author.