Ultrasound-guided fine needle aspiration cytology of axillary lymph nodes in breast cancer patients. A preoperative staging procedure.

Currently, axillary lymph node dissection is increasingly being replaced by the sentinel node procedure. This method is time-consuming and the full immunohistochemical evaluation is usually only first known postoperatively. This study was designed to evaluate the accuracy of preoperative ultrasound-guided fine needle aspirations (FNAs) for the detection of non-palpable lymph node metastases in primary breast cancer patients. We evaluated the material of 183 ultrasound-guided FNAs of non-palpable axillary lymph nodes of primary breast cancer patients. The cytological results were compared with the final histological diagnosis. Ultrasound-guided FNA detected metastases in 44% (37/85) of histologically node-positive patients, in 20% of the total patient population studied. These pecentages are likely to be higher when women with palpable nodes are included. Cytologically false-negative and false-positive nodes were seen in 28 (15%) and three cases (1.6%), respectively. Interestingly 25% (n=7) of the false-negative nodes, revealed micrometastases on postoperative histology. The sensitivity was 57%, the specificity 96%. We conclude that ultrasound-guided FNA of the axillary lymph nodes is an effective procedure that should be included in the preoperative staging of all primary breast cancer patients. Whether lymph nodes are palpable or not, it will save considerable operating time by selecting those who need a complete axillary lymph node dissection at primary surgery and would save a significant number of sentinel lymph node dissections (SLNDs).