REDWOOD CITY, Calif., July 21 (San Francisco News Online) — For a healthy adult thinking about paying for a full-body MRI, the big question is not whether the scan can find anything. It can. The question, federal regulators and specialty medical groups say, is whether it finds enough that matters to justify the cost, the extra testing that often follows, and the chance of being misled by a result that turns out not to be serious.
A recent Fox News report about a former “Bachelor” contestant whose preventive scan found a brain tumor has put whole-body MRI back in the spotlight. But major medical organizations still do not recommend routine whole-body MRI screening for people without symptoms or specific risk factors.
What is a full-body MRI?
A full-body MRI, sometimes called a whole-body or total-body scan, uses magnetic fields and radio waves to create images of many parts of the body in one session. Unlike CT scans, MRI does not use ionizing radiation, according to the American Cancer Society.
That has made the test attractive to some people who want an early look for cancer or other hidden problems. Companies such as Prenuvo have marketed the scan as a way to detect hundreds of conditions, including early tumors, CBS San Francisco reported.
Why are doctors cautious?
The Food and Drug Administration says it knows of no scientific evidence that scanning people without symptoms provides more benefit than harm. The American College of Radiology said in an April 2023 statement that there is not enough evidence to recommend total-body screening for patients who have no symptoms, no risk factors and no family history pointing to disease.
Other groups have taken similar positions. The U.S. Preventive Services Task Force has given asymptomatic pancreatic cancer screening in adults who are not known to be at high risk a “D” rating, meaning harms outweigh benefits. The American College of Preventive Medicine says doctors should not use whole-body scans for early tumor detection in people without symptoms of illness.
The main worry is not that the scan finds nothing. It is that it finds too much.
The American Cancer Society says full-body MRI can show “spots” or “shadows” that may be normal variations in the body. Those findings can lead to follow-up scans, biopsies, specialist visits and anxiety before doctors know whether anything is actually wrong. The society says insurance companies rarely pay for the scan because it is not standard medical care.
What are the possible downsides?
Doctors and medical groups warn about several problems:
- false positives, where the scan suggests disease that is not really there
- incidental findings, sometimes called incidentalomas, that are unrelated to the reason for the scan
- unnecessary follow-up tests or procedures
- overdiagnosis, which means finding something that would never have caused harm
- overtreatment
- false reassurance, if a normal scan makes someone think future disease is impossible
- high out-of-pocket cost
Matthew Davenport, a radiology and urology professor at the University of Michigan, told ABC News that the harms can come from invasive testing, surgery or follow-up of findings with uncertain benefit. In a JAMA editorial reported by ABC, Davenport and Dr. Scott Reeder said no major medical group recommends whole-body MRI for the general population because the benefits remain unproven.
The American Cancer Society says the risk is in the “downstream effects.” Dr. Rebecca Smith-Bindman, a UCSF radiology researcher, told CBS San Francisco that there is “not a stitch of evidence” that the scan helps people live longer or better, and she warned that false positives could trigger a lot of extra testing.
Could it still catch something serious early?
Yes, it can find abnormalities, and in some cases that may lead to an important diagnosis. That is the appeal of the scan, and it is what has drawn attention after the reported brain tumor case.
But experts say a single example does not prove that routine screening helps the broader population. The question for public health is whether finding a problem earlier actually improves survival, quality of life or treatment choices. On that point, regulators and specialty groups say the evidence is still lacking.
Cleveland Clinic says whole-body MRI may detect some problems before symptoms start, but it also warns about abnormal findings, false negatives and overdiagnosis. The clinic notes that a scan can miss disease and that not every finding needs treatment.
What does this mean for San Francisco readers?
The Bay Area has become part of the national conversation because of CBS San Francisco’s reporting on Prenuvo and its local expert source at UCSF. For people weighing an elective scan, the practical takeaway from the medical guidance is simple: a full-body MRI is not a routine screening test for healthy adults.
That does not mean no one should ever get one. It does mean the decision should be tied to symptoms, family history or a clinician’s advice rather than marketing claims alone. For most people, the American Cancer Society, the FDA and radiology groups say the known tradeoffs still outweigh the unproven upside.
