Sentinel Lymph Node Biopsy After Neo-adjuvant Chemotherapy in Breast Cancer

Abstract

The timing of sentinel node biopsy in the setting of neo-adjuvant chemotherapy for breast cancer is controversial. Sentinel node biopsy performed after neo-adjuvant chemotherapy may save patients with a nodal response the morbidity of an axillary lymph node dissection. A retrospective review of prospectively collected data compared sentinel node biopsies performed after patients had received neo-adjuvant chemotherapy with patients who had not received neo-adjuvant chemotherapy. Demographic factors, tumor characteristics, and the results of the sentinel node biopsies and completion lymph node dissections (when applicable) were compared. A total of 231 axillary procedures (224 patients) were evaluated. The patients who received neo-adjuvant chemotherapy (NEO; N=52) were younger, had higher grade tumors, were more likely to have a mastectomy, and were more likely to have ER-negative and HER-2/neu positive tumors than the patients who did not receive neo-adjuvant chemotherapy (NON; N=179). The mean clinical tumor size in the neo-adjuvant group was 4.5cm (±1.8) prior to chemotherapy; the post-chemotherapy pathologic size was 1.4cm (±1.3). A sentinel node was identified in all cases. There were no significant differences between the groups in the mean number of sentinel nodes removed (NEO=3.3; NON=3.1; p=0.545), the percentage of positive axillae (NEO=24%; NON=21%; p=0.776) or the mean number of positive sentinel nodes (NEO=1.3; NON=1.5; p=0.627). There was no difference in the percentage of completion lymph node dissections with additional positive nodes (NEO=20%; NON=35%; p=0.462); there was a difference in the number of nodes removed in the completion lymph node dissections (mean NEO=12.0; NON=16.4; p=0.047). Sentinel node biopsy performed after neo-adjuvant chemotherapy appears to be an oncologically sound procedure and may save some patients the morbidity of a complete lymph node dissection.

CK19 expression in breast tumours and lymph node metastasis after neoadjuvant therapy

“…However, recent studies comparing two cohorts of patients, treated and not treated prior to surgery, have not demonstrated significant differences in the rate of successful sentinel node identification or in the results of the SLNB assay. These authors concluded that it is technically feasible to identify the sentinel nodes after NSBT, and that the accuracy of SLNB remains similar to that in early cancer not susceptible to neoadjuvant therapy …”

“…Although breast‐conserving surgery is the goal of the local treatment of breast cancer after NSBT, the management of the axilla is not clear. Given that the axillary status represents the most important independent prognostic factor in breast cancer, complete axillary lymphadenectomy has represented the choice of treatment, but in recent years conservative options with the sentinel node assay have been proposed …”

“…Given that the axillary status represents the most important independent prognostic factor in breast cancer, complete axillary lymphadenectomy has represented the choice of treatment, but in recent years conservative options with the sentinel node assay have been proposed. 1,2,26,27 There is no consensus about the timing for performance of the SLNB. If sentinel nodes are evaluated prior to neoadjuvant treatment, accurate information about lymph node status is obtained, contributing to the design of precise radiotherapy and chemotherapy strategies.…”

“…These authors concluded that it is technically feasible to identify the sentinel nodes after NSBT, and that the accuracy of SLNB remains similar to that in early cancer not susceptible to neoadjuvant therapy. 2,3,26,27,32 When an SLNB procedure is indicated, a new question may arise: which is the most appropriate technique with which to evaluate the nodes after systemic treatment? In recent years, different molecular methods for analysing sentinel nodes have been proposed.…”

Neoadjuvant Therapy in Breast Cancer

“…Several studies now have demonstrated that, in patients who are clinically node negative at diagnosis, the SN can be identified over 97% of the time with low false negative rates. 17,18 Several studies also support the view that performing the SNB after NCT allows downstaging of the axilla and results in fewer patients being subjected to full axillary node dissection (ALND), with its attendant risk of chronic lymphedema. Proponents of performing the SNB prior to NCT believe that knowledge of the state of the axilla prior to the initiation of chemotherapy is critical for prognostication.…”