FDA Approves First Blood Test for Colon Cancer Screening

The U.S. Food and Drug Administration (FDA) has approved a new blood test for colon cancer, marking a significant development in the fight against this leading cause of cancer deaths.

Guardant Health, the test’s manufacturer, stated that the FDA has cleared its Shield test for screening adults aged 45 and older who have an average risk of colon cancer. While not a replacement for colonoscopies, the Shield test offers a noninvasive alternative for screening.

Physicians can currently order the Shield test as a laboratory test for patients at a cost of $895. However, FDA approval is expected to increase insurance coverage from both private and government sources.

The test works by detecting DNA fragments released from tumor cells and precancerous growths. A study published in March indicated that the test accurately identified 83% of cancers, but only a small percentage of the precancerous growths detected by colonoscopies, which are considered the gold standard for colon cancer screening. The test missed 17% of cancers, a performance comparable to stool-based tests.

In addition to identifying tumors, colonoscopies also play a crucial role in preventing colon cancer by removing precancerous growths known as polyps.

However, some individuals avoid colonoscopies due to the inconvenience of taking time off work or the preparation process, which requires drinking a strong laxative to cleanse the bowels. The U.S. recommends colon cancer screening for healthy adults between the ages of 45 and 75 who are at average risk for the disease.

Guardant Health has announced that physicians can administer the Shield test by simply taking a blood sample. The company plans to launch its product “in the near future.”

The current rate of colon cancer screening in the U.S. stands at almost 60%, falling short of the 80% goal set by the American Cancer Society and other organizations for age-eligible adults.