REDWOOD CITY, Calif., July 21 (San Francisco News Online) — A recent Fox News report about an unnamed former “Bachelor” contestant whose preventive scan found a brain tumor before symptoms has renewed interest in full-body MRI screening. But for most healthy adults, the bigger question is not whether these scans can find anything. It is whether finding more things early actually leads to better health.
What is a full-body MRI?
A full-body, or whole-body, MRI uses magnets and radio waves to create images of the body. The American Cancer Society says MRI does not use ionizing radiation, which is the kind of radiation used in CT scans.
Companies market these scans as a way to look for cancer, heart disease and other problems before symptoms start. Prenuvo, for example, has said its scan can detect more than 500 conditions, including early tumors, according to CBS San Francisco.
Why are doctors cautious?
Major medical groups do not recommend routine whole-body MRI screening for people who do not have symptoms or a known higher risk.
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. The American College of Radiology says there is not enough evidence to recommend total-body screening for patients without symptoms, risk factors or family history suggesting disease. The American College of Preventive Medicine says doctors should not use whole-body scans for early tumor detection in people without symptoms.
In a San Francisco example of the debate, UCSF radiology researcher Dr. Rebecca Smith-Bindman told CBS San Francisco, “There’s not a stitch of evidence it will do either of those things,” referring to helping people live longer or better.
What can go wrong with the scans?
The main concern is not radiation. It is what happens after the scan.
The American Cancer Society says the risk comes from the possible downstream effects. A scan may show a spot or shadow that turns out to be normal variation, or a finding that is not dangerous. Those incidental findings, sometimes called incidentalomas, can lead to more tests, biopsies, procedures, worry and cost.
The ACS says insurance companies rarely pay for full-body MRI because it is not standard medical care. WebMD says a scan can cost $2,000 or more and usually is not covered by insurance.
Cleveland Clinic also warns that a scan can miss problems and can lead to overdiagnosis, which means finding a condition that might never have caused symptoms or death. Its guidance says full-body MRI can also create false alarms and false reassurance.
Why does one tumor story get so much attention?
A case like the one reported by Fox News is powerful because it is easy to understand: a scan found something before symptoms began. But doctors and medical groups say one case does not prove that routine screening helps most people.
That is the key divide in the full-body MRI debate. A scan can find abnormalities. The harder question is whether those findings improve health enough to justify the chance of false positives, extra testing and cost.
That debate is especially visible in the Bay Area, where CBS San Francisco reported on growing interest in Prenuvo scans and quoted UCSF experts who said the evidence has not shown clear health benefits for healthy people.
For now, the broad message from the FDA and major medical groups is consistent: full-body MRI may have a role in specific medical situations, but they do not view it as a routine screening test for the general population.
