What is a Whole Body MRI?
Contrary to the name, a “whole body MRI” typically involves a MRI scan from the head down to the pelvis, and doesn’t include ones’ limbs. In Canada, whole body MRIs are done through private imaging centres, and are only available through a physician referral. These scans have been growing in popularity, fueled by celebrity endorsers. For anyone considering a whole body MRI, it’s important to understand the potential pros and cons.
What are the Potential Benefits?
Those who advocate for whole body MRI point to cases where a whole-body MRI has identified an early-growing cancer or other potentially serious condition before any symptoms have developed. This, in theory, would allow for earlier actions to be taken. Considering the dangers of late cancer diagnosis, this potentially could improve outcomes.
Other benefits include the fact that contrary to CT scans or nuclear scans, MRI scans carry no radiation, and a large area of the body can be scanned in one appointment.
What are Potential Concerns?
The biggest concern is with over-diagnosis and false positive results. The MRI cannot always tell the difference between a potentially cancerous lesion which requires action and a benign one. As a result, this can lead to further tests, such as CT scans which carry radiation, invasive biopsies, or the need for long-term monitoring with serial scans every 6 – 12 months to make sure the lesion isn’t growing. This process can be anxiety-provoking, and in some cases such as with invasive biopsies can cause harm.
In addition, a whole-body MRI is relatively quick and may not provide the same level of detail as a dedicated MRI of a specific body part.
Lastly, MRI is also not always the best type of imaging for looking at certain body parts, such as bones.
My Recommendation
Where I’ve personally landed on this topic is that for most healthy, younger individuals a whole-body MRI is neither necessary nor recommended. For select individuals who are at higher risk, such as those with a long-term smoking history, strong family history of cancer, or increased risk for cancers of the pancreas and biliary tree, there’s a potential role. Either way, it’s a conversation making sure an individual understands the pros and cons before they have the scan done.