There's no universal rulebook for using full-body MRI scans to check for cancer, so different hospitals do it differently—making it hard to compare results or use it reliably everywhere.

There's no universal rulebook for using full-body MRI scans to check healthy people for cancer, so different hospitals do it differently—making it hard to trust the results or use them widely in doctors' offices.

Doctors use whole-body MRI scans to look for cancer in people who feel fine, but since everyone uses different scan rules, the results can vary a lot — making it hard to trust or use these scans reliably.

Doctors use full-body MRI scans to look for cancer in people who feel fine, but since everyone uses different scan settings, results can vary a lot — making it hard to trust or use these scans widely.

When doctors didn’t have a regular test to check for cancer, a special full-body MRI scan found cancer in nearly 7 out of 10 people—so it might help catch cancers that other tests miss.

Using whole-body MRI to screen everyone for cancer isn't a good idea right now because it often misses cancers, finds too many harmless things that cause worry, isn't done the same way everywhere, and we don't know if it actually helps people live longer or healthier lives.