Study of internal mammary sentinel lymph node biopsy in breast cancer patients after neoadjuvant chemotherapy

BACKGROUND AND OBJECTIVES Sentinel lymph node biopsy (SLNB) is an accurate method for axillary staging in patients with early breast cancer. The aim of this study was to evaluate the accuracy and the feasibility of SLNB in breast cancer patients who had received preoperative (neoadjuvant) chemotherapy. METHODS Patients with advanced breast cancer stage II or III who were treated with neoadjuvant chemotherapy were included in the study. Sentinel lymph node (SLN) identification and biopsy was attempted and performed, and axillary lymph node dissection (ALND) was performed in the same surgical procedure after SLNB. The histopathologic examination of the SLNs and the dissected axillary lymph nodes was performed and nodal status was compared. RESULTS Thirty patients were included in the study. After peritumoural injection of technetium-99m labelled human albumin and subareolar subcutaneous injection of blue dye, the SLNs could be identified in 26/30 patients (identification rate 86.7%). In 4/30 patients (13.3%) SLNs could not be identified. In 25/26 patients (96.2%) SLNs accurately predicted the axillary status. Eleven patients had negative SLNs and negative nodes in ALND. Six patients had positive SLNs and positive nodes in ALND. In eight patients SLNs only were positive and nodes in ALND were negative. One patient had a false-negative SLNB, calculating a false-negative rate of 6.7% (1/15). CONCLUSIONS SLNB is a well introduced technique for axillary staging in patients with early breast cancer. The accuracy of SLNB after neoadjuvant chemotherapy is similar to patients with primary surgery. SLNB could be an alternative to ALND in a subgroup of patients after neoadjuvant chemotherapy, and therefore could reduce morbidity due to surgery in those patients. Due to small numbers of patients, further evaluation in this subset of patients is required.