Role of Percutaneous Needle Biopsy of Axillary Lymph Nodes to Evaluate Node Positive Breast Cancer after Neoadjuvant Chemotherapy

The aim of the study was to evaluate the role of ultrasound guided fine needle aspiration cytology (FNAC) in the restaging of node positive breast cancer after neoadjuvant chemotherapy (NAC). From January 2016 – October 2018, 90 node positive stage IIA-IIIC breast cancer cases undergoing NAC were included in the study. The largest, most superficial and the most caudal axillary node metastasis confirmed by fine needle aspiration cytology (FNAC) was marked with clip. After NAC, restaging of axilla was performed with ultrasound and FNAC of the marked and/or the most suspicious axillary node. Of the 90 cases, 58 with available ultrasound guided percutaneous needle biopsy data were further evaluated. Axilla conserving surgery was performed in 37 of 58 cases and axillary lymph node dissection (ALND) in 21 of 58 cases. False Positive Rate (FPR) of FNAC after NAC was 12%, False Negative Rate (FNR) — 58%, sensitivity — 54%, specificity — 82%, accuracy 62%. FNAC after NAC had low FPR and was found to be useful in predicting residual axillary disease and to streamline surgical decision making regarding ALND. However, FNR was unacceptably high and FNAC alone was not able to predict ypCR and omission of further axillary surgery.