Paging Dr. Frischer: Whole body scans

I am often asked by my patients whether I think that they should have a “whole-body scan.” These typically use magnetic resonance imaging (MRI), computed tomography (CT), and/or bone density (DEXA) scans. Modern technology is amazing, and scans like these save lives every day. They can detect tumors and internal bleeding, track diseases, and are especially useful in cases of injury or specific syndromes. However, they are being marketed as a means to detect diseases, such as cancer, earlier. Are whole-body scans worth it?

·      Let’s start with money: Preventive whole-body scans are usually not covered by insurance. Out-of-pocket costs may range from around $250 to over $2,500.

·      These scans may involve radiation exposure: CT exposes the patient to some radiation. MRI uses powerful magnetic fields, but without any form of radiation. DEXA applies specifically targeted low-dose X-ray beams. Ultrasound uses no radiation.

·      False positive results: Whole-body scans can produce incidental findings that are difficult to interpret. This leads to further testing and possibly even an unnecessary biopsy or surgery. The process of one test leading to more tests and procedures is known as a “cascade of care,” starting with the discovery of an unexplained and often ultimately harmless mass, nodule, or other abnormality. Subsequent procedures can lead to infections, bleeding, discomfort, complications and of course higher costs.

·      False-negative results: These occur when test results appear to be normal, when in fact they are not. A whole-body scan may miss something important and even lead the patient to skip necessary care.

Many of us have seen stories of these scans identifying potentially fatal cancers before they have a chance to spread. In reality, among those who have no particular risk for the disease, the odds of catching an aggressive cancer within such a tiny window of time are exceedingly slim. As an example, the U.S. Preventive Services Task Force gave these scans a D rating, their lowest, for pancreatic cancer screening in adults without symptoms who are not at high risk. The task force concluded that the potential harm outweighs the benefits. Aside from very rare instances, there is no evidence that these scans change outcomes. 

As a doctor, I order very specific, highly-sensitive tests when I have reason to be suspicious. These whole-body scans are marketed directly to patients and are often non-sensitive and non-specific. I would not recommend them for the average or asymptomatic patient, due to the high risk of false results, subsequent unnecessary tests, and high costs. I would urge you to consult with your doctor before considering such a step.