Data Shows Semiautomated Analysis of Combidex-Enhanced MRI Feasible

Advanced Magnetics and Cytogen have announced that clinical data published in the December 2004 issue of Public Library of Science (PLoS) Medicine shows for the first time the feasibility of computer-assisted lymph node staging using Combidex, Advanced Magnetics' investigational molecular imaging agent.

Combidex (ferumoxtran-10) consists of iron oxide nanoparticles for use in conjunction with magnetic resonance imaging (MRI) to aid in the differentiation of cancerous from noncancerous lymph nodes.

In the 70-patient study, the magnetic tissue parameters of cancer metastases and normal unmatched lymph nodes were measured in pre- and post-Combidex enhanced images using a learning dataset consisting of 97 histologically proven nodes from 36 patients. The accuracy of a variety of these parameters obtained in a semiautomated manner was then prospectively tested against 216 histologically validated lymph nodes from the remaining 34 patients.

Unique magnetic characteristics were found that accurately distinguished metastatic from normal nodes with an overall sensitivity of 98 percent and specificity of 92 percent. The parameters were applied to datasets in a semiautomated fashion and used to map the nodes to a 3-D reconstruction of the vascular anatomy to provide complete nodal anatomy for different primary cancers.