Localization of metalloporphyrin-induced "specific" enhancement in experimental liver tumors: comparison of magnetic resonance imaging, microangiographic, and histologic findings.

Abstract

RATIONALE AND OBJECTIVES:

We investigated the tumor specificity of gadolinium mesoporphyrin (Gd-MP) and manganese tetraphenylporphyrin (Mn-TPP) as magnetic resonance (MR) imaging contrast agents.

METHODS:

Fifteen rats with multiple hepatocellular carcinomas and eight rats with implanted Novikoff hepatomas were given intravenous injections of either Gd-MP or Mn-TPP at 0.05 mmol/kg, which was compared with nonspecific gadopentetate dimeglumine (0.3 mmol/kg). T1-weighted spin-echo images were obtained before and up to 48 hr after injection and compared with corresponding microangiograms and histologic specimens. The relative enhancement of organs and tumors was plotted as a function of time.

RESULTS:

Initially, both metalloporphyrins behaved as nonspecific agents, similar to gadopentetate dimeglumine, and enhanced the tumor by perfusion and diffusion. However, metalloporphyrins, but not gadopentetate dimeglumine, caused a delayed (> or = 3 hr) enhancement in some compartments of certain lesions. The MR imaging-microangiography-histology matching technique revealed that those compartments were actually nonviable components, including necrosis (n = 10), thrombosis (n = 7), and cystic secretion (n = 3), but not viable tumor tissue.

CONCLUSION:

Metalloporphyrins did not prove to be tumor specific. However, the observed affinity for nonviable tissue has elicited other potential applications for these agents.

• Authors: Y Ni, G Marchal, J Yu, G Lukito, C Petré, M Wevers, A L Baert, W Ebert, C S Hilger, F K Maier
• Journal: Academic radiology (Acad Radiol) Vol. 2 Issue 8 Pg. 687-99 (Aug 1995) ISSN: 1076-6332 [Print] United States
• PMID: 9419626 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Contrast Media
• Mesoporphyrins
• Metalloporphyrins
• manganese tetraphenylporphyrin
• Gadolinium
• Gadolinium DTPA

Topics

• Angiography
• Animals
• Carcinoma, Hepatocellular (diagnosis, metabolism)
• Cell Division (drug effects)
• Contrast Media
• Disease Models, Animal
• Dose-Response Relationship, Drug
• Gadolinium (pharmacokinetics)
• Gadolinium DTPA (pharmacokinetics)
• Image Enhancement (methods)
• Liver Neoplasms, Experimental (diagnosis, metabolism)
• Magnetic Resonance Imaging
• Male
• Mesoporphyrins (pharmacokinetics)
• Metalloporphyrins (pharmacokinetics)
• Neoplasm Transplantation
• Rats
• Rats, Wistar
• Tissue Distribution