REDWOOD CITY, Calif., July 21 (San Francisco News Online) — A recent Fox News report about a preventive whole-body MRI that found a brain tumor in an unnamed former “Bachelor” contestant has renewed interest in scans marketed as a way to catch disease early. In San Francisco, where UCSF radiology researcher Dr. Rebecca Smith-Bindman has been one of the most visible critics of routine screening scans, the question is not whether the technology can find abnormalities. It is whether finding more things actually helps people live longer or better.
For most healthy adults, major medical groups say the answer is still unclear.
What a full-body MRI is
A full-body MRI uses magnets and radio waves to create pictures of the body. The American Cancer Society says MRI does not expose a person to ionizing radiation, unlike CT scans.
That difference is one reason some people see MRI as a gentler kind of screening test. Companies such as Prenuvo also market whole-body MRI as a way to look for many diseases before symptoms appear. CBS San Francisco reported that Prenuvo says its scans can detect more than 500 conditions.
Why doctors are cautious
The Food and Drug Administration says it knows of no scientific evidence showing that scanning 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 people who have no symptoms, no known risk factors and no family history that points to serious disease.
Other medical groups have taken similar positions. The American Academy of Family Physicians recommends against full-body scans for early tumor detection in people without symptoms. The American College of Preventive Medicine says doctors should not use whole-body scans for early tumor detection in people who do not have symptoms of illness. And the U.S. Preventive Services Task Force gives pancreatic cancer screening a “D” rating for asymptomatic adults who are not known to be at high risk, meaning the harms outweigh the benefits.
The promise and the problem
The appeal is easy to understand: if a scan can find a tumor early, maybe treatment can start sooner. That is the story behind the recent attention.
But experts say the problem is that whole-body MRI often finds things that are not dangerous. The American Cancer Society says scans can turn up “spots” or “shadows” that may be normal variations in the body. Those findings can lead to more tests, more worry and sometimes procedures that turn out not to be needed.
Dr. Fuller, quoted by the American Cancer Society, said the risk comes from the possible downstream effects. Those can include anxiety, follow-up imaging, biopsies and the chance that a person is treated for something that would never have caused harm.
That last point is called overdiagnosis. Cleveland Clinic says overdiagnosis means finding a condition that would not have gone on to cause major symptoms or death.
There is also the opposite problem: a scan can suggest everything is fine when a disease is actually there. Cleveland Clinic notes that false negatives are possible.
What the San Francisco experts are saying
In CBS San Francisco, Dr. Smith-Bindman of UCSF said there is “not a stitch of evidence” that full-body MRI can help people live longer or better. She also warned that there could be “tremendous numbers of false positives,” meaning results that look worrisome but do not point to real disease.
That matters because every questionable result can lead to more appointments, more scans and more cost.
The American Cancer Society says insurance companies rarely pay for full-body MRI because it is not part of standard medical care. When people pay on their own, the cost can be high.
What to make of a “good news” story
A scan that finds a real tumor before symptoms start can sound like proof that whole-body MRI works. But doctors say one story does not answer the bigger question.
In a JAMA editorial reported by ABC News, Matthew Davenport and Dr. Scott Reeder said no major medical group recommends whole-body MRI for the general population because the benefits have not been proven.
That is why the current debate is not just about what the scan can show. It is about whether the findings change outcomes enough to justify the risk of false alarms, extra testing and cost.
For San Francisco readers seeing the scans advertised as a wellness upgrade, the basic medical message from the FDA, the ACR and other groups is consistent: full-body MRI may find abnormalities, but for people without symptoms or specific risk factors, there is still no clear proof that routine screening does more good than harm.
