Variation in axillary node dissection influences the degree of nodal involvement in breast cancer patients

Background and Objectives: The number of positive axillary lymph nodes pred icts prognosis and is often important in determining adjuvant chemotherapy in breast cancer patients. This study was undertaken to determine if differ ences in the extent of axillary node dissection would after the number of r eported positive nodes. Methods: The study population consisted of 302 patients with invasive breas t cancer who underwent complete (level I/II/III) axillary lymph node dissec tion. Assuming that all patients had undergone a level I/II dissection, it was determined how frequently a patient's nodal category (0, 1-3, 4-9, >10 positive nodes) would have been altered if a level I or level I/II/III diss ection were performed. Results: Assuming that all 302 patients had undergone a level Lm dissection , performing only level I dissection would have resulted in a change in nod al category in 15.9% of all patients and 36.1% of patients with positive no des. The corresponding changes for a level I/II/III dissection would have b een 4.3% and 9.5%, respectively. Conclusions: Variations in the level of axillary node dissection for breast cancer can result in significant changes in the number of positive axillar y nodes. This can potentially bias adjuvant chemotherapy recommendations if treatment decisions are based on this prognostic factor. (C) 2000 Wiley-Li ss, Inc.