Portland, OR: Ferumoxytol-enhanced Magnetic resonance imaging is as effective as gadolinium-enhanced MRI for the detection of intracranial metastatic disease, suggests a recent study in the American Journal of Roentgenology. This could allow the use of ferumoxytol-enhanced Magnetic resonance imaging in improving workup and monitoring of brain metastases in case gadolinium-enhanced Magnetic resonance imaging is contraindicated.
Bronwyn E. Hamilton, Department of Radiology, Oregon Health & Science University, Portland, OR, and colleagues investigated whether ferumoxytol-enhanced MRI is as effective as standard-of-care gadolinium-enhanced MRI for the detection of intracranial metastatic disease.
The researchers retrospectively reviewed all patients who underwent imaging as part of two ongoing ferumoxytol-enhanced and gadolinium-enhanced MRI protocol studies to compare the number and size of enhancing metastatic lesions. Enhancing metastases on ferumoxytol-enhanced MR images and control on gadolinium-enhanced MR images were measured independently by two neuroradiologists. The size and number of metastases were compared on intraindividual basis. They recorded primary diagnoses. Differences in cubic root of volume between gadolinium-enhanced and ferumoxytol-enhanced MRI were compared using a linear mixed-effects model.
In this study, the researchers analyzed images from 19 patients with brain metastases (seven with lung cancer, three with melanoma, three with breast cancer, two with ovarian cancer, one with uterine cancer, one with carcinoid tumor, and one with renal cell carcinoma).
Key findings of the study include:
Reviewer 1 identified 77 masses on ferumoxytol-enhanced MRI and 72 masses on gadolinium-enhanced MRI.
Reviewer 2 identified 83 masses on ferumoxytol-enhanced MRI and 78 masses on gadolinium-enhanced MRI.
For reviewer 1, ferumoxytol-enhanced MRI showed a mean tumor size measuring 1.1 mm larger in each plane compared with gadolinium-enhanced MRI.
For reviewer 2, ferumoxytol-enhanced MRI showed a mean tumor size measuring 1.0 mm larger in each plane.
No significant differences in number of metastases or tumor sizes were observed between contrast agents or reviewers.
"Our results demonstrate that intracranial metastatic disease detection with ferumoxytol-enhanced MRI is not inferior to detection with gadolinium-enhanced MRI," concluded the authors.
The study, "Ferumoxytol-Enhanced MRI Is Not Inferior to Gadolinium-Enhanced MRI in Detecting Intracranial Metastatic Disease and Metastasis Size," is published in the American Journal of Roentgenology.
DOI: https://www.ajronline.org/doi/abs/10.2214/AJR.19.22187