Morbidity and complexity involved in lymph node staging via surgical resection and biopsy calls for staging techniques that are less invasive. While visible blue dyes are commonly used in locating sentinel lymph nodes, since they follow tumor-draining lymphatic vessels, they do not provide a metric to evaluate presence of cancer. An area of active research is to use fluorescent dyes to assess tumor burden of sentinel and secondary lymph nodes.

The goal of this work was to successfully deploy and test an intra-nodal cancer-cell injection model to enable planar fluorescence imaging of a clinically relevant blue dye, specifically methylene blue – used in the sentinel lymph node procedure – in normal and tumor-bearing animals, and subsequently segregate tumor-bearing from normal lymph nodes. This direct-injection based tumor model was employed in athymic rats (6 normal, 4 controls, 6 cancer-bearing), where luciferase-expressing breast cancer cells were injected into axillary lymph nodes. Tumor presence in nodes was confirmed by bioluminescence imaging before and after fluorescence imaging. Lymphatic uptake from the injection site (intradermal on forepaw) to lymph node was imaged at approximately 2 frames/minute. Large variability was observed within each cohort.

Date Published: 4 March 2015
PDF: 5 pages
Proc. SPIE 9311, Molecular-Guided Surgery: Molecules, Devices, and Applications, 93110D (4 March 2015); doi: 10.1117/12.2081196

Published in SPIE Proceedings Vol. 9311:
Molecular-Guided Surgery: Molecules, Devices, and Applications
Brian W. Pogue; Sylvain Gioux, Editor(s)