Role of Ultrasound-guided Fine-needle Aspiration of Axillary Lymph Nodes in Preoperative Staging of Breast Cancer: Correlation with Final Pathological Results and Staging

Objective: To retrospectively assess the sensitivity and specificity of ultrasound-guided fine-needle aspiration of axillary lymph nodes for preoperative breast cancer staging, using histological findings as a reference standard. Methods: This was a retrospective study involving 95 consecutive adult patients having ultrasound-guided fine-needle aspiration of axillary lymph nodes performed from January to December 2010. In all, 45 (47%) of the patients had newly diagnosed carcinoma of breast. Four (4%) had axillary lymph node recurrences from a breast or lung tumour. The remainder (n = 46; 48%) did not have malignancy, showing incidentally enlarged reactive axillary lymph nodes only. Results: The ages of the 45 women in the study group ranged from 30 to 78 (mean, 51) years. The mean primary breast cancer tumour size was 2.8 cm (range, 0.4-11.0 cm). Regarding the 45 axillary biopsies in this study, only six samples (13%) gave inconclusive results. Among these, four underwent surgery and three had positive lymph nodes. In all, 25 (56%) yielded positive fine-needle cytology findings, whilst in the remainder (n = 14; 31%), cytology was negative for malignancy. Twenty-three (51%) yielded metastatic carcinoma in the sentinel node biopsy or dissected axillary lymph node. Patients with positive ultrasound-guided fine-needle aspiration results and those with negative results were further analysed with their pathological results. Lymph nodes were more likely to be positive for metastatic disease with increased pathological tumour size. Ultrasound-guided fine-needle aspiration of axillary lymph nodes for preoperative staging is highly sensitive and specific, with satisfactory 95% confidence intervals. Conclusion: Ultrasound-guided fine-needle aspiration of axillary lymph nodes was a highly sensitive and specific non-surgical means of staging breast cancer. Positive cytology for metastatic disease is sufficient to replace sentinel node biopsy and proceed to axillary lymph node dissection, and thus decrease the duration of anaesthesia and associated morbidity.