Usefulness of Combined Sestamibi Scintimammography, Axillary Ultrasonography and FNA Cytology in Reducing the Number of Sentinel Node Procedures in Patients with Early-stage Breast Cancer

Background: Intraoperative analysis of the sentinel lymph node (SLN) status is currently performed in patients with breast cancer (BC) undergoing surgery. Axillary node (AN) metastases are present in up to 60% of cases, but the risk is only 30% in patients with early stage (T1) BC. The aim of this study was to evaluate the usefulness of 99mTc-sestamibi scintimammography (SSM), axillary ultrasonography (US) and US-guided fine-needle aspiration (FNA) cytology together in detecting axillary metastases preoperatively and their potential role in reducing the number of SLN procedures. Patients and Methods: A series of 86 consecutive women (median age 57 years, range 30-72) with confirmed BC and clinically negative nodes (T1N0) underwent both SSM and US prior to surgery. US-guided FNA cytology was performed in all the patients with suspicious AN on US, or positive SSM and ultrasonographically visualized enlarged nodes. Results: Final pathology showed 4 pT1bN0, 1 pT1bN1, 60 pT1cN0 and 21 pT1cN1 BC. The sensitivity, specificity, and accuracy were 59.1%, 93.7% and 84.9% for SSM, 63.6%, 90.6% and 83.7% for US, and 72.7%, 97.8% and 90.7% for SSM and US together. Using FNA cytology the specificity reached 100%, but the sensitivity did not increase. A combined method using radioisotope and blue dye was used for SLN biopsy. The procedure was omitted in patients with FNA cytology showing AN metastases (N=14, 16.3%) and they underwent level I-II axillary dissection, as well as those with positive SLN biopsy on frozen section (8 out of 72, 11.1%). Conclusion: In patients with BC, preoperatively selected by SSM and US in whom US-guided axillary FNA cytology has shown the presence of AN metastases, the SLN biopsy can be avoided and AN dissection should be the primary procedure.