Abstract

Lymph node size, the accumulation of a nodal lymphotrophic contrast agent (LCDIO), and MRI were compared as methods for detecting nodal metastases in an experimental murine model. Lymph node metastases (B16-F1 melanoma expressing green fluorescent protein (GFP) and C57BL/6 mice) were generated to obtain a wide spectrum of nodes, including normal nodes and nodes bearing micrometastases, small metastases, or large metastases. Nodal uptake of LCDIO was measured using (111)Indium-labeled LCDIO and was found to be lower in micrometastastic nodes (4.20 +/- 1.4%ID/gm) than in normal nodes (8.60 +/- 0.22% ID dose/gram, P