Histological Distribution of Magnetic Nanoparticles in Sentinel Lymph Nodes in Breast Cancer

Laura Johnson¹, Sarah Pinder¹, Margaret Hall-Craggs², Michael Douek¹

Contrast enhanced MRI scans of the axilla may improve pre-operative identification of lymph node metastases in patients with breast cancer, identifying those patients who require formal axillary lymph node dissection and potentially sparing those with a clear axilla any axillary surgery at all. Understanding how superparamagnetic iron-oxide nanoparticles distribute within the normal and the metastasis containing lymph node may aid the identification of abnormal nodes. Histological examination of 85 sentinel lymph nodes following injection with SPIO demonstrates preferential uptake by macrophages within the sinuses of the node. Iron does not accumulate in areas of the node containing metastases.