Can Carcinoembryonic Antigen (CEA) be elevated without cancer or significant disease?

From the Guidelines

Yes, Carcinoembryonic Antigen (CEA) can be elevated without cancer or significant disease. CEA is a protein that can be found in higher than normal amounts in people with certain types of cancers, particularly colorectal cancer, but elevated levels are not always indicative of cancer. Several benign conditions can cause CEA elevations, including inflammatory bowel disease, pancreatitis, liver disease (such as cirrhosis or hepatitis), lung infections like pneumonia or bronchitis, smoking, and certain benign gastrointestinal disorders 1.

Key Points to Consider

• Normal CEA levels are typically below 3 ng/mL for non-smokers and below 5 ng/mL for smokers.
• The elevation in non-cancerous conditions usually results from inflammation or tissue damage that causes increased production or decreased clearance of CEA.
• CEA is not recommended as a screening test for cancer in the general population but is more useful for monitoring known cancer cases for recurrence or treatment response.
• If you have an elevated CEA level without known cancer, your healthcare provider will likely recommend additional testing to determine the cause rather than assuming cancer is present. Some examples of non-cancerous conditions that can cause elevated CEA levels include gastritis, peptic ulcer disease, diverticulitis, liver diseases, chronic obstructive pulmonary disease, diabetes, and any acute or chronic inflammatory state 1.

Clinical Implications

• It is essential to interpret CEA levels in the context of the patient's overall clinical picture, including medical history, physical examination, and other diagnostic tests.
• A rising CEA level during treatment should prompt re-evaluation and consideration of an alternative treatment strategy, but it is crucial to consider exceptions such as chemotherapy-associated CEA increases 1.

From the Research

CEA Elevation Without Disease

• Carcinoembryonic Antigen (CEA) can be elevated in various conditions beyond cancer, including noncancer diseases and in healthy individuals, particularly those older than 65 years 2.
• Studies have shown that CEA levels can be increased in patients with inflammatory bowel disease, such as ulcerative colitis and Crohn's disease, even in the absence of cancer 3.
• Elevated CEA levels have also been observed in other non-neoplastic conditions, including acute and chronic inflammations, benign tumors, renal or hepatic insufficiency, with values typically less than 10 ng/ml 4.
• The increase in CEA levels in these conditions can be attributed to various factors, including tissular, physiological, metabolic, circulating, and methodological factors 4.
• It is essential to consider these factors when interpreting CEA test results in clinical practice to avoid misdiagnosis or unnecessary further testing 2, 5, 4.

Conditions Associated with Elevated CEA

• Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease 3, 6.
• Non-neoplastic conditions, such as acute and chronic inflammations, benign tumors, renal or hepatic insufficiency 4.
• Aging, with healthy individuals older than 65 years showing increased CEA levels 2.
• Other diseases, including lung fibrosis, pancreatic cancer, uremia, chronic obstructive pulmonary disease, colon cancer, Alzheimer's disease, rectum cancer, and lung cancer, which have been found to have high median levels of serum CEA 2.