REDWOOD CITY, Calif., July 21 (San Francisco News Online) — A recent report about a preventive scan finding a brain tumor has put full-body MRI back in the spotlight. But for most people, the real question is not whether a whole-body scan can ever find something important. It is whether the test is worth the cost and the risk when major medical groups say routine screening in healthy people is still not proven.
What is a full-body MRI?
A full-body MRI is a magnetic resonance scan that images many parts of the body in one visit. Unlike CT scans, MRI does not use ionizing radiation, according to the American Cancer Society.
Companies such as Prenuvo market whole-body MRI as a way to detect more than 500 conditions, including some cancers early. But the Food and Drug Administration says it knows of no scientific evidence that scanning people without symptoms offers more benefit than harm.
Why are doctors cautious?
Several major medical groups do not recommend routine whole-body MRI screening for the general public.
The American College of Radiology said in an April 2023 statement that there is not enough evidence to recommend total-body screening for people with no symptoms, no risk factors and no 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.
The U.S. Preventive Services Task Force also gives pancreatic cancer screening in asymptomatic adults who are not known to be at high risk a D rating, meaning the harms outweigh the benefits.
What are the downsides?
The main concern is what happens after the scan.
The American Cancer Society says full-body MRI can show “spots” or “shadows” that turn out to be normal variations in the body. Those findings can lead to anxiety, more imaging, follow-up tests and sometimes procedures that were never needed.
The society also says insurance companies rarely pay for full-body MRI because it is not part of standard medical care.
In a CBS San Francisco interview, UCSF radiology researcher Dr. Rebecca Smith-Bindman said there is “not a stitch of evidence” that the scan helps people live longer or better, and she warned that false positives can lead to more testing.
A JAMA editorial by Matthew Davenport and Dr. Scott Reeder said no major medical group recommends whole-body MRI for the general population because the benefits are still unproven. Davenport has said the harms can come from invasive testing or surgery that follow uncertain findings.
Can a scan still find something real?
Yes. The recent brain tumor story is one reason the test draws attention. A whole-body MRI can uncover real problems before symptoms appear.
But doctors say one success story does not prove the scan should be used widely. A test can sometimes find an important problem and still cause more harm than good for most healthy people if it also finds many harmless abnormalities.
That is why the debate has stayed alive: a whole-body scan may feel reassuring, but a normal result does not guarantee the body is disease-free, and an abnormal result is not always dangerous. For Bay Area readers, the issue is especially local because UCSF experts have been among the voices warning against routine use of the test while companies continue to market it as preventive screening.
