Is Sentinel Lymph Node Biopsy a Viable Alternative to Axillary Lymph Node Dissection in Breast Carcinoma Patients Who Have Received Neo-Adjuvant Chemotherapy?

Abstract

Background Sentinel lymph node biopsy (SLNB) is based on the hypothesis that lymph from a primary solid neoplasm drains into one or more sentinel nodes, which are the first nodes at risk for harbouring occult metastatic disease. Sentinel lymph node biopsy has replaced axillary lymph node dissection (ALND) as the standard method for axillary staging in clinically node-negative patients. It avoids the complications associated with ALND and allows assessment of nodal status in patients with clinically node-negative breast cancer. Aims and objectives The aim of this study is to determine the false negative rate and identification rate of SLNB in breast cancer patients who received neoadjuvant chemotherapy (NACT). Materials and methods We conducted a hospital-based prospective study that included 19 patients who presented with early breast cancer and were node-positive. Post NACT, intraoperatively, methylene blue and radiocolloid dye were injected in the subareolar region. During the surgery, the blue and hot nodes identified were dissected, sent for frozen section analysis, and subsequently submitted for histopathological evaluation. This was followed by a standard-level I/II/III axillary clearance with histopathological examination. Results The false-negative rate of SLNB is 25%. Sentinel lymph node biopsy was more accurate with stage II than stage III tumours, and in patients who downstaged from stage II to any stage following NACT, it was more accurate than downstaging from stage III. The average number of sentinel nodes identified was 1.9, with the maximum being seven and the minimum being one. A total of 25 sentinel lymph nodes were identified in 13 patients, with an identification rate of 68.42%. Conclusions The main clinicopathological factors that influence the false negative rate of SLNB after NACT are axillary lymph node status, stage of the tumour at presentation, and tumour downstaging. For patients for whom sentinel nodes cannot be harvested, ALND should be done.