MRS and MRI Studies of the Structure and Function of Tumor Interstitial Matrix.
Abstract
The interstital matrix creates a barrier to therapeutic agent delivery. To overcome this barrier we must study the matrix characteristics and the effect of manipulations and therapy. We proposed to establish the use of magnetic resonance (MR) methods for studying tumor interstitium. We wished to: (1) determine by MR the collagen and glycosaminoglycan (GAG) concentration and diffusivity of small solutes in the interstitial matrix in breast cancer. (2) investigate the effect of antiestrogen therapy on the interstitial matrix composition in estrogen dependent breast cancer. (3) study the effect of enzymatic modulation and biological response modifiers on the interstitial matrix. In pilot studies, Sodium MR was found to have insufficient resolution for determining GAG in tumor tissue. We developed a proton MR technique involving the contrast agent Gd-DTPA2- and showed that compared with sodium methods it was equally sensitive, and provided far higher spatial resolution. The latter allowed us to observe matrix accumulation in polymer scaffolds seeded with cells. We observed that the high cellularity of tumors affected the estimate of GAG content from the MR measurement. Subsequent theoretical analyses established a framework accounting for cellularity. We began to characterize diffusion imaging and its dependence on hydration in extracellular matrices.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1997
- Accession Number
- ADA336744
Entities
People
- Rakesh Jain
Organizations
- Massachusetts General Hospital