Accuracy of axillary ultrasound in the diagnosis of nodal metastasis in invasive breast cancer: a review.

Axillary lymph node status is the most important prognostic factor in early-stage breast cancer. Sentinel lymph node biopsy is used to determine the need for axillary node dissection. This technique incurs cost associated with radio-isotope administration and use of the operating room. Accordingly, there is a need to preoperatively identify patients with nodal metastases who can proceed directly to axillary dissection. Axillary ultrasound has increasingly been used to determine nodal status prior to surgery. It has been shown to be a sensitive and specific modality in the detection of nodal metastases. When combined with fine-needle aspiration, the specificity of this modality significantly increases. Here we present a current review of the usefulness of preoperative axillary ultrasound in early and locally advanced breast cancer patients with and without fine-needle aspiration biopsy. Based on this review, we estimate the proportion of patients that can be spared a sentinel lymph node biopsy and the concomitant benefit of axillary ultrasound in terms of cost.