Contrast-enhanced MR imaging of tumor-bearing mice treated with tumor necrosis factor

This paper reports the biologic effects of tumor necrosis factor (TNF) studied in a mouse fibrosarcoma model with MR imaging enhanced with an intravascular contrast agent, albumin Gd-DTPA. Nonenhanced and enhanced images (spin echo; 310/15 [repetition time msec/echo time msec]) were obtained with a 2.0-T CSI-II imager/spectrometer serially over 60 minutes, commencing 1 hour after the injection of TNF. The most marked differential tumor enhancement was shown in the tumor rim (59% for TNF vs 41% for control), which corresponded with strong Evans blue staining. Data indicate that TNF produces a change in tumor capillary permeability that can be identified and quantitatively assessed with contrast-enhanced MR imaging