For the most part, MRI imaging for prostate cancer is safe. In some cases, contrast agents are needed to be injected into the human body in order to get a better picture or scan. Many of the contrast agents utilized contain the heavy metal, gadolinium. These injected agents help physicians see internal organs, blood vessels and other tissues more clearly.
In late 2017, the FDA declared that all gadolinium-containing contrast agents must carry the warning about how they could be retained in the body and potentially cause kidney injury. Most of the gadolinium is eliminated by the kidneys. If one’s kidney function is normal, there has been no direct link with these contrast agents to any specific health issue. The brand name Gadavist (gadobutrol) is often used for MRI screening of prostate cancer and active surveillance. Much lower levels of this agent are used compared to other agents. The FDA is now asking the manufacturers of gadolinium agents to conduct more human and laboratory studies to determine the safety of these agents. Thus far, the one real adverse effect noticed with these agents is in a small group of patients with pre-existing kidney failure, a condition known as nephrogenic systemic fibrosis. More recently, researchers in Belgium and Japan expressed concern that gadolinium-based contrast agents showed preliminary evidence of depositing in the part of the brain called the cerebellum.
Here is a list of eight (8) of the most widely used gadolinium contrast agents and their brand and generic names and levels of concern. The following three have lower levels of retention and are of less concern; a) Dotarem (Gadoterate Meglumine); b) Gadavist (Gadobutrol); and, Prohance (Gadotridol). The following five have high levels of retention; a) Eovist (Gadoxetate Disodium); b) Magnevist (Gadobenate Dimeglumine); c) Multihance (Gadobenate Dimeglumine); d) Omniscan (Gadodiamide); and e) Optimark (Gadoversetamide).
The body retains less gadolinium when using agents that have what is known as a macrocyclic (large rings) chemical structure, as in Dotarem, Gadavist and Prohance. Gadolinium agents that have a linear chemical structure have higher levels in the body after using them.
So the next time you have an MRI with contrast, inquire which of the gadolinium agents are being used. If it is one with linear structure or higher retention, one should ask for alternatives or seek out another imaging facility.
This post is an excerpt from an article written by Mark Moyad, MD, MPH, Jenkins / Pokempner Director of Alternative Medicine, University of Michigan Medical Center. It was published in the summer 2018 issue of the Prostate Digest, Volume 21, Issue 2, published by the Prostate Cancer Research Institute.
P.S. So now you know how to respond when you see one of those notorious lawyer ads on TV asking if you “have ever taken an MRI with contrast and developed _______. You may be entitled to substantial compensation.”