Improved False-Negative Rates with Intraoperative Identification of Clipped Nodes in Patients Undergoing Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy

Identification and resection of a clipped node was shown to decrease the false-negative rate (FNR) of sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) for patients presenting with initially node-positive breast cancer. Between March 2014 and March 2016, a prospective trial analyzed 98 patients with axilla-positive locally advanced breast cancer (T1-4, N1-3) to assess the feasibility and efficacy of placing clips into most suspicious biopsy-proven node. The study considered blue, radioisotope active, and suspiciously palpable nodes as sentinel lymph nodes (SLNs). The SLN identification rate was 87.8%. The median age of the patients with an SLNB (n = 86) was 44 years (range 28-66 years). Of these patients, 77 (88.4%) had cT1-3 disease, and 10 (11.6%) had cT4 disease. The majority of the patients (n = 66, 76.7%) had cN1, whereas 21 patients (23.3%) had cN2 and cN3. A combined method was used for 37 patients (43%), whereas blue dye alone was used for the remaining patients (57%). The clipped node was the SLN in 70 patients (81.4%). For the patients with cN1 before NAC, the FNR was found to be 4.2% (1/24) when the clipped node was identified as an SLN. However, the FNR was estimated to be as high as 16.7% (1/6) for the patients with cN1 before NAC when the clipped node was found to be a non-SLN. The study results also suggest that axillary dissection could be omitted for patients presenting initially with N1 disease and with a negative clipped node as the SLN after NAC due to the low FNR.