The effect of prior breast biopsy method and concurrent definitive breast procedure on success and accuracy of sentinel lymph node biopsy

It has been suggested that sentinel lymph node (SLN) biopsy for breast cancer may be less accurate after excisional biopsy of the primary tumor compared with core needle biopsy. Furthermore, some have suggested an improved ability to identify the SLN when total mastectomy is performed compared with lumpectomy. This analysis was performed to determine the impact of the type of breast biopsy (needle vs. excisional) or definitive surgical procedure (lumpectomy vs. mastectomy) on the accuracy of SLN biopsy. Methods: The University of Louisville Breast Cancer Sentinel Lymph Node Study is a prospective multi-institutional study. Patients with clinical stage T1-2, NO breast cancer were eligible. All patients underwent SLN biopsy and completion level I/II axillary dissection. Statistical comparison was performed by X² analysis. Results: A total of 2206 patients were enrolled in the study. There were no statistically significant differences in SLN identification rate or false-negative rate between patients undergoing excisional versus needle biopsy. The SLN identification and false-negative rates also were not statistically different between patients who had total mastectomy compared with those who had a lumpectomy. Conclusions: Excisional biopsy does not significantly affect the accuracy of SLN biopsy, nor does the type of definitive surgical procedure.