Magnetic Detection of the Sentinel Lymph Node in Ex Vivo Tissue with Colorectal Cancer

Abstract

A new method for sentinel lymph node detection was investigated by ex-vivo experiments in colorectal cancer. A dispersion of superparamagnetic iron oxide (SPIO) nanoparticles was injected in the resected tissue around the tumor. A magnetic probe with a 2 nd order gradiometer configuration was used to localize the sentinel lymph node with accumulated SPIO nanoparticles. Additional analysis of SPIO content was performed on the resected lymph nodes. High-field MRI and conventional microscopy revealed the presence and distribution of SPIO inside the lymph nodes. Magnetometry confirmed SPIO content in lymph nodes and could give an estimate of the amount of SPIO uptake.