FDA Panel Recommends Shield Blood Test for Colorectal Cancer Screening
A blood test designed to screen for colorectal cancer is one step closer to approval by the U.S. Food and Drug Administration (FDA). On Thursday night, the Medical Devices Advisory Committee, an FDA advisory panel, recommended the approval of the Shield blood test, finding it safe, effective, and beneficial despite potential risks.
Shield Blood Test Nears FDA Approval
Guardant Health, the company behind Shield, is seeking FDA premarket approval for the test to screen for colorectal cancer in individuals aged 45 and older at average risk. While Shield is not the first blood-based screening tool for colorectal cancer, it offers another option for detecting a type of cancer that increasingly affects younger Americans.
Shield is currently available commercially, but FDA approval would expand its availability and coverage, providing another screening choice. Guardant Health expects the FDA to decide on Shield’s premarket approval later in 2024. However, FDA approval is not guaranteed, as the agency sometimes diverges from its advisors’ recommendations.
Understanding Colorectal Cancer
Colorectal cancer starts in the colon or rectum and is often referred to as colon or rectal cancer, depending on its origin. According to the American Cancer Society (ACS), most colorectal cancers develop from polyps, growths on the inner lining of the colon or rectum. While most polyps are benign, some can become cancerous over many years.
Symptoms of colorectal cancer include changes in bowel habits, rectal bleeding, blood in the stool, abdominal pain, weakness, fatigue, and sudden weight loss. Despite an overall decline in cancer deaths, the ACS reported an alarming increase in colon cancer among younger adults earlier this year. Colon cancer is now the leading cause of death among men under 50 and the second leading cause of death among women in the same age group.
Traditional Colorectal Cancer Screening Methods
Colonoscopies remain the gold standard for screening colorectal cancer. During this procedure, a doctor inserts a colonoscope—a long, thin, flexible tube with a camera on the end—through the anus to examine the rectum and colon, potentially biopsying any suspicious tissues or polyps.
Stool tests can also detect blood not visible to the naked eye, possibly indicating cancer. The United States Preventative Services Task Force recommends that adults aged 45 and older with average risk undergo colorectal cancer screening. This includes a stool test every one to three years or a colonoscopy every 10 years for asymptomatic individuals.
