REDWOOD CITY, Calif., July 21 (San Francisco News Online) — A recent Fox News report about a preventive full-body MRI that found a brain tumor has renewed interest in a test that some clinics market as a way to spot disease before symptoms start. But for most people, the bigger question is not whether an MRI can find something unexpected. It is whether routine whole-body screening helps healthy people live longer or stay healthier. The Food and Drug Administration says it knows of no scientific evidence showing that whole-body scanning of people without symptoms provides more benefit than harm.
What is a full-body MRI?
A full-body MRI uses magnets and radio waves to create images of much of the body. The American Cancer Society says MRI does not expose a person to ionizing radiation, unlike a CT scan. That makes it different from x-ray-based imaging, but it does not make the scan harmless or automatically useful as a screening test.
Why is it in the news?
CBS San Francisco reported that Prenuvo markets the scan as a way to detect more than 500 conditions, including cancer at an early stage. That kind of pitch has helped turn full-body MRI into a wellness trend in some circles. A separate Fox News report about a preventive scan that found a brain tumor in a former “Bachelor” contestant has also drawn new attention.
Why don’t doctors recommend it routinely?
Major medical groups do not recommend routine whole-body MRI screening for people who have no symptoms and no specific risk factors. The American College of Radiology said in an April 2023 statement that there is not enough evidence to justify total-body screening for patients with no clinical symptoms, risk factors or family history suggesting serious disease. The American Academy of Family Physicians and the American College of Preventive Medicine also recommend against using whole-body scans to look for early tumors in people without symptoms.
In an ABC News report on a JAMA editorial, Matthew Davenport and Dr. Scott Reeder said no major medical group recommends whole-body MRI for the general population because the benefits remain unproven. Davenport said the harms come from invasive testing, surgeries or follow-up of findings that may have uncertain benefit.
What are the main risks?
The biggest problem is that a scan can find things that are not dangerous. The American Cancer Society says full-body MRI can turn up “spots” or “shadows” that may be normal variations in the body. Those incidental findings can lead to more tests, biopsies or procedures, and they can also cause anxiety. The society says the risk comes from the downstream effects.
Doctors also worry about overdiagnosis, which means finding a condition that may never have caused symptoms or death. The American Cancer Society and Cleveland Clinic both warn that a normal scan can also give false reassurance, because not every disease is visible on one scan and some problems may appear later.
There is also the issue of cost. The American Cancer Society says insurance companies rarely pay for full-body MRI because it is not part of standard medical care.
What does this mean for a Bay Area reader?
For people in San Francisco and elsewhere, the new attention does not change the basic medical consensus. Full-body MRI may sound reassuring, and in some cases it can uncover real disease. But the FDA, the American College of Radiology, the American Academy of Family Physicians and the American College of Preventive Medicine say routine screening of healthy, symptom-free adults has not been shown to do more good than harm.
That is why doctors generally reserve imaging for people with symptoms, known risk factors or a specific reason to look.
