By: Dan Sperling, MD

Multiparametric magnetic resonance imaging (mpMRI) of the prostate has been shown to be highly significant and specific in detecting significant prostate cancer. The use of more than one imaging parameter, or functional sequence, confers the ability to characterize abnormal tissue as cancer. One of the functional parameters that is routinely included is dynamic-contrast enhanced MRI (DCE-MRI).

The value of DCE-MRI is the identification of a tumor’s blood supply. This is based on a closely timed sequence of scans as a contrast agent injected into the bloodstream infiltrates blood vessels in and around the prostate gland within seconds, then washes out. A tumor has the ability to generate new blood vessels by which to sustain itself and feed its growth. However, these blood vessels are less organized and more permeable than healthy blood vessels, and the way in which these vessels take up the contrast agent and the speed with which it washes out is revealed by the series of scans.[i]

For DCE-MRI of the prostate, a gadolinium-based contrast agent is used. Gadolinium is a soft, silvery white chemical element. For contrast purposes in MRI patient scans, the atoms are bonded with special molecules that preserve its imaging properties while overcoming any toxicity. Gadolinium is considered very safe for adults. However, the use of gadolinium-based agents is restricted to those with healthy kidney function, since kidneys do the work of flushing out all gadolinium via urine within 24 hours of administration. This means that those with poor kidney function, as measured by a simple blood test, cannot undergo DCE-MRI and as a result may miss an important clue regarding the nature of any tumor activity. In addition, in 2015 it was reported that evidence points to the possibility that some types of gadolinium-based agents may deposit a very small amount of gadolinium in the brain where it may remain for years.[ii]

In March, 2013 the U.S. Food and Drug Administration (FDA) approved the use of a gadolinium-based contrast agent called Dotarem (released in 1989 by Gueret Pharmaceuticals, France). Dotarem was already widely used in Europe and other countries around the world. It was originally developed for neurological MRI of the delicate brain and spinal cord structures of the central nervous system because it does not deposit residue in the brain. This also made it safer for use even in children and those with compromised kidney function.

The use of Dotarem in mpMRI of the prostate is slowly on the rise. For example, the authoritative Dutch team out of Radboud University Nijmegen Medical Center, with whom the Sperling Prostate Center frequently collaborates, used Dotarem for its clinical study of mpMRI and early risk stratification of candidates for Active Surveillance.[iii] It was likewise used by a Dutch-U.S. team to discriminate between prostate cancer and benign conditions that can be mistaken for prostate malignancy.[iv]

As with all gadolinium-based contrast agents, Dotarem comes with safety warnings regarding dosage and ensuring that patients do not have high risk kidney issues. However, there is cause for optimism since its increased safety allows use with a wider range of patients. The Sperling Prostate Center now makes Dotarem available for prostate mpMRI because of its increased safety features.

[i] Verma S, Turkbey B, Muradyan N, Rajesh A et al. Overview of dynamic contrast-enhanced MRI in prostate cancer diagnosis and management. Am J Roent. 2012 Jun;198(6):1277-88.

[ii] https://www2.rsna.org/timssnet/media/pressreleases/14_pr_target.cfm?ID=810

[iii] Hoeks C, Somford D, van Oort I, Vergunst H et al. Value of 3-T Multiparametric Magnetic Resonance Imaging and Magnetic ResonanceYGuided Biopsy for Early Risk Restratification in Active Surveillance of Low-Risk Prostate Cancer. Invest Radiol 2014;49:165-172.

[iv] Litjensa GJ, Elliott R, Shihc N, Feldman M et al. Distinguishing prostate cancer from benign confounders via a cascaded classifier on multi-parametric MRI. Medical Imaging 2014: Computer-Aided Diagnosis, edited by Stephen Aylward, Lubomir M. Hadjiiski, Proc. of SPIE Vol. 9035, 903512 · © 2014 SPIE · CCC code: 1605-7422/14/$18 · doi: 10.1117/12.2043751.