A multi-center retrospective analysis of ultrasound-guided fine needle aspiration biopsy for detecting additional positive axillary node metastasis in early breast cancer

Abstract

This study evaluates the effectiveness of ultrasound-guided fine needle aspiration biopsy (US-FNAB) in assessing additional positive axillary lymph node (ALN) metastasis following sentinel lymph node biopsy (SLNB) in clinically ALN-negative or N1 cases, aiming to refine patient management. A multi-center, retrospective analysis included 7617 patients with cT1-2 and cN0-1, who underwent US-FNAB for ALN and proceeding to SLNB or axillary lymph node dissection (ALND). Metastatic patterns were assessed, particularly focusing on correlations with positive FNAB results and additional ALN metastasis found during ALND, with statistical significance evaluated. Of those undergoing SLNB, 97.5% exhibited macrometastasis. In the SLNB-only group, 2.4% had 3 and more than 3 positive lymph node, compared to 19.2% in the SLNB & ALND group (P < 0.01). Among ALND patients, 63.3% had positive nodes, significantly higher in those with positive FNAB (91.9% vs. 22.8%, P < 0.001). Additionally, 40.9% were found to have additional positive ALNs in patients who underwent ALND following positive SLNB, with rates significantly higher in those with positive FNAB (60.3% vs. 35.4%, P < 0.001). LVI positivity, pT2-3, SLNR > 50% and positive FNAB were independent predictors of additional ALN metastasis in patients undergoing ALND after positive SLNB (P < 0.05). The proportion of additional positivity escalated with the number of positive SLNs. US-FNAB significantly improves the detection of additional ALN metastasis, guiding more effective strategy for ALN surgical decision-making. Our findings support the incorporation of US-FNAB into clinical practice to improve patient stratification and optimize treatment outcomes in early-stage breast cancer management.

Keywords: Axillary lymph node dissection; Early breast cancer; Fine needle aspiration biopsy; Sentinel lymph node biopsy; Ultrasound-guided.

Fig. 1

Number and metastasis of lymph nodes in SLNB surgery. (A) The median number of lymph nodes in the SLNB only group and the SLNB & ALND group. (B) The proportions of patients with different number of positive SLNs in positive SLNB population. (C) The proportions of patients with different number of positive SLNs in negative FNAB group of positive SLNB population. (D) The proportions of patients with different number of positive SLNs in positive FNAB group of positive SLNB population. (E) The comparison of the proportion of patients with lymph node metastases between negative FNAB and positive FNAB group in SLNB only population. (F) The comparison of the proportion of patients with lymph node metastases between negative FNAB and positive FNAB group in SLNB & ALND population.

Fig. 2

Percentage of positive lymph nodes during ALND surgery. (A) The proportion of positive ALNs in patients with ALND. (B) The proportion of positive ALNs in cN0 patients with ALND. (C) The proportion of positive ALNs in cN1 patients with ALND.

Fig. 3

Percentage of additional positive lymph nodes in patients undergoing ALND after SLNB. (A) The proportion of additional positive ALNs in patients undergoing ALND after negative SLNB. (B) The proportion of additional positive ALNs in cN0 patients undergoing ALND after negative SLNB. (C) The proportion of additional positive ALNs in cN1 patients undergoing ALND after negative SLNB. (D) The proportion of additional positive ALNs in patients undergoing ALND after positive SLNB. (E) The proportion of additional positive ALNs in cN0 patients undergoing ALND after positive SLNB. (F) The proportion of additional positive ALNs in cN1 patients undergoing ALND after positive SLNB.

Fig. 4

The relationship between additional positive lymph node metastasis in ALND after SLNB and the number of positive SLN results when at least one additional positive lymph node in ALND. (A) Result in whole population. (B) Result in cN0 patients. (C) Result in cN1 patients.