Manganese-enhanced MRI of minimally gadolinium-enhancing breast tumors.

Abstract

PURPOSE:

To investigate the potential of manganese (Mn)-enhanced MRI for sensitive detection and delineation of tumors that demonstrate little enhancement on Gd-DTPA.

MATERIALS AND METHODS:

Eighteen nude rats bearing 1 to 2 cm in diameter orthotopic breast tumors (ZR75 and LM2) were imaged on a 3 Tesla (T) clinical scanner. Gd-DTPA was administered intravenously and MnCl2 subcutaneously, both at 0.05 mmol/kg. T1 -weighted imaging and T1 measurements were performed precontrast, 10 min post-Gd-DTPA, and 24 h post-MnCl2 . Tumors were excised and histologically assessed using H&E (composition and necrosis) and CD34 (vascularity).

RESULTS:

Most tumors (78%) demonstrated little enhancement (< 20% change in R1 ) on Gd-DTPA. MnCl2 administration achieved greater and more uniform enhancement throughout the tumor mass (i.e., not restricted to the tumor periphery), with R1 changing over 20% in 72% of tumors. MnCl2 -induced R1 changes compared with Gd-induced changes were significantly greater in both ZR75 (P < 0.01) and LM2 tumors (P < 0.05). Histology confirmed very low vascularity in both tumor models, and necrotic areas were well delineated only on Mn-enhanced MRI.

CONCLUSION:

Mn-enhanced MRI is a promising approach for detection of low-Gd-enhancing tumors.

• Authors: Tameshwar Ganesh, Reza Bayat Mokhtari, Mosa Alhamami, Herman Yeger, Hai-Ling Margaret Cheng
• Journal: Journal of magnetic resonance imaging : JMRI (J Magn Reson Imaging) Vol. 41 Issue 3 Pg. 806-13 (Mar 2015) ISSN: 1522-2586 [Electronic] United States
• PMID: 24591227 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2014 Wiley Periodicals, Inc.

Chemical References

• Contrast Media
• Manganese
• Gadolinium DTPA

Topics

• Analysis of Variance
• Animals
• Breast Neoplasms (diagnosis)
• Contrast Media
• Disease Models, Animal
• Female
• Gadolinium DTPA
• Humans
• Image Enhancement (methods)
• Magnetic Resonance Imaging
• Manganese
• Rats
• Rats, Nude