Sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with operable breast cancer and positive axillary nodes at initial diagnosis

Aim: To evaluate the utility of the sentinel lymph node biopsy (SLNB) in patients with operable breast cancer and positive axillary nodes at initial diagnosis treated with neoadjuvant chemotherapy (NAC).

Material and methods: A prospective study was performed from January 2008 to December 2012 in 52 women, mean age 50.7 years, with infiltrating breast carcinoma T1-3, N1, M0 (1 bilateral, 7 multifocal) treated with epirubicin/cyclophosphamide, docetaxel and trastuzumab in Her2/neu-positive patients. Axillary evaluation included physical examination, axillary ultrasound, and ultrasound-guided core needle biopsy of any suspicious lymph node. The day before surgery, 74-111 MBq of (99m)Tc-albumin nanocolloid was injected periareolarly. All patients underwent breast surgery, with SLNB and complete axillary lymph node dissection (ALND). The SLNs were examined by frozen sections, hematoxylin-eosin staining, immunohistochemical analysis or one-step nucleic acid amplification assay (OSNA).

Results: Mean tumor size: 3.5 cm. Histologic type: 81.1% invasive ductal carcinoma. Complete response of primary tumor was clinical 43.4%, pathological 41.5%. All patients were clinically node-negative after NAC. Pathological complete response of axillary node was 42.2%. SLN identification rate was 84.9%. Axilla was positive in the pathology study in 6 of 8 patients without nanocolloid migration. SLN accurately represented the axillary status in 95.5%. False negative rate was 8.3%. SLN was the only positive node in 68.2% of patients. Mean number of SLN removed was 1.9 and of nodes resected from the ALND 13.2.

Conclusion: SLN biopsy after NAC is a feasible and accurate tool in patients with operable breast cancer T1-3, N1 and clinically node-negative after therapy.