ABSTRACT
The axillary lymph node status is the most important prognostic index of breast cancer, so the accurate assessment of axillary lymph node metastasis has always been a hot topic in breast cancer research. Today, sentinel lymph node biopsy (SLNB) has become the preferred surgical procedure for axillary lymph node negative early breast cancer. The selection of tracers is also a key link in the study of SLNB and lymphatic drainage area of breast cancer. Traditional tracers (blue dye, nuclide and fluorescent tracers, etc.) have many problems, such as allergy, poor localization specificity and radioactivity to human body, which limit their promotion and application in clinic. However, superparamagnetic iron oxide nanoparticle (SPION) can effectively improve these shortcomings and has the advantages that other tracers cannot replace. It can be an ideal tracer for SLNB of breast cancer and has a good application prospect. This article mainly describes the current application of SPION in SLNB of breast cancer, and outlines the advantages and disadvantages of this tracer.