After surgical removal, RSL can eliminate specimen radiographs when the radiologist accurately places the seed and the pathologist grossly identifies the lesion. If small microcalcifications are noted before surgery, then specimen radiographs may be necessary. RSL reduced requirements for specimen radiographs, decreased OR time, improved incision placement, and improved resections to clear margins.

The evaluation of sentinel lymph nodes (SLNs) for the presence of malignant epithelial cells is essential to the staging of breast cancer patients. Recently, increased attention has focused on the possibility that epithelial cells may reach SLNs by benign mechanical means, rather than by metastasis. The purpose of this study was to test the hypothesis that pre-SLN biopsy breast massage, which we currently use to facilitate the localization of SLNs, might represent a mode of benign mechanical transport. We studied 56 patients with invasive and/or in situ ductal carcinoma and axillary SLNs with only epithelial cells and/or cell clusters (< or =0.2 mm in diameter and not associated with features of established metastases) detected predominantly in subcapsular sinuses of SLNs on hematoxylin and eosin- and/or anti-cytokeratin-stained sections. No patient had an SLN involved by either micro- or macro-metastatic carcinoma. Epithelial cells and cell clusters, < or =0.2 mm in size and without features of established metastases, occurred more frequently in the SLNs of patients who underwent pre-SLN biopsy breast massage (P < 0.001, chi2 test). The latter finding supports the hypothesis that pre-SLN biopsy breast massage is a mode of benign mechanical transport of epithelial cells to SLNs.

This study validates the prognostic stratification of patients with a complete pathologic axillary response to neoadjuvant chemotherapy. The addition of SLN biopsy to cN0 patients before treatment increased accurate nodal staging by 53%, eliminated completion axillary lymph node dissection in 15%, and demonstrated an improved prognosis in 28% of pCRAX patients. SLN biopsy before treatment provides accurate staging of cN0 patients; allows acquisition of standard treatment markers, prognostic biomarkers, and microarray analysis; and affords prognostic stratification after treatment.