Is a Full-Body Scan Effective at Detecting Cancer?
Some imaging and medical centers have started offering full-body scans as an early cancer detection test for healthy people with no cancer-related symptoms. But do the risks of a full-body scan outweigh the potential benefits?
A full-body scan is usually a type of computed tomography (CT) scan that scans your whole body, starting below your chin. These scans can also be done using MRI or PET scans, but CT scans are the most common. Typically, these scans are used to check the extent of injuries or internal bleeding and can also monitor the progression of cancer.
Recently, imaging and health centers have started to offer full-body scans as an elective cancer detection service. This service is offered to people who are healthy and who typically don’t have cancer-related symptoms.
Although this might seem like a good tool for early detection, major medical organizations don’t recommend full-body scanning as a cancer screening method. Research is still being done, but at this time, the risks are thought to outweigh the benefits.
This article takes a closer look at full-body scans, how they work, and the risks involved with this type of screening.
Americans see their primary care doctors less often than they did a decade ago. Adults under 65 made nearly 25% fewer visits to primary care providers in 2016 than they did in 2018, according to National Public Radio. In the same time period, the number of adults who went at least a year without visiting a primary care provider increased from 38% to 46%.
Full-body scans are usually only done when warranted, such as to help doctors see internal bleeding or to get a better picture of the full extent of a traumatic injury. They can also be used to see if cancer is spreading or is responding to treatment.
Full-body scans aren’t considered an effective screening and early detection tool for cancer. The use of full-body scanning for healthy, asymptomatic people isn’t recommended by the U.S. Food and Drug Administration (FDA) or by any major medical organizations.
Researchers are looking into the benefits of full-body scans as screenings for people at high risk of certain cancers, especially lung and colon cancer, but the benefits of this test haven’t been proven. Right now, full-body scans are only recommended in very specific medical situations.
Some imaging and medical centers promote full-body scans as a method of early cancer detection. Most of the time, CT scans are offered. PET scan imaging or full-body MRI scans may also be offered by imaging centers.
On the surface, this method makes sense. After all, images taken of your whole body should be a good way to find tumors before they start causing symptoms. But none of these full-body scans are a recommended screening method.
Traditional imaging for cancer is focused on small areas and looks for tumors known to be linked to specific cancers. For instance, a mammogram gives a detailed look at breast tissue.
Full-body scans look at your entire body. In doing so, they can miss small and hidden tumors and lead to a false sense of safety. This may lead to some people ignoring symptoms that may be caused by cancer.
Additionally, healthy people who get full-body scans can receive “false positives.” This means they could receive abnormal results even though they don’t have cancer. These false positives can lead to unnecessary testing, costs, and stress.
One of the primary risks of a full-body scan is radiation exposure. CT and PET scans both use radiation to create detailed images of your body’s internal structures. Your body is exposed to large amounts of radiation during CT or PET full-body scans. This exposure can increase your risk of cancer.
When a full-body scan is used to check the extent of an injury or to see how cancer is progressing, the benefit tends to outweigh the risk. Because the benefit of a full-body scan as a cancer detection tool is currently unproven, the FDA doesn’t recommend full-body scans for cancer detection.
Other risks of full-body scans include false positives that can lead to unnecessary testing and false negatives that can cause people to ignore their symptoms.
Other types of cancer detection can also have risks, but the benefits of these tests have been proven. For example, mammograms may sometimes result in false positives, but they’ve been shown to be effective as an early detection method for breast cancer.
Colonoscopies can sometimes cause complications such as bleeding, but, like mammograms, the benefit of this screening as an early detection tool for colon cancer has been proven.
Additionally, neither of these methods exposes your body to high amounts of radiation. In fact, the only other type of cancer testing that exposes your body to radiation is a CT scan used for people at high risk of lung cancer. In that case, a much smaller amount of radiation is concentrated on a much smaller body area compared with a full-body scan.
What types of imaging tests are most commonly used to detect cancer?
There are many types of imaging tests used for early cancer detection. Some of these tests are recommended for people in certain age groups and those of a particular sex. Others are for people at high risk of specific cancers.
Cancer imaging tests include:
