Carcinoembryonic Antigen (CEA), Pleural Fluid
An adjuvant to cytology and imaging studies to differentiate between nonmalignant and malignant causes of pleural effusions
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Pleural effusions occur as a consequence of either nonmalignant conditions (including congestive heart failure, pneumonia, pulmonary embolism, and liver cirrhosis) or malignant conditions (including lung, breast, and lymphoma cancers). Diagnosing the cause of an effusion can be difficult, often requiring cytological examination of the pleural fluid and imaging studies of the pleural tissue. Analysis of various tumor markers in pleural fluid has shown that these markers can differentiate between effusions caused by nonmalignant and malignant conditions and can enhance cytology and imaging findings.
Carcinoembryonic antigen (CEA) is a glycoprotein produced during fetal development. Nonsmoking, healthy adults typically produce low to undetectable levels of CEA. Serum concentrations of CEA may be elevated in patients with certain malignancies that secrete CEA into circulation, including medullary thyroid carcinoma and breast, gastrointestinal tract, colorectal, liver, lung, ovarian, pancreatic, and prostate cancers.
Pleural fluid concentrations of CEA have been reported to be elevated in patients with certain malignancies. Malignancies that can secrete CEA and elevate serum CEA concentrations, including lung, breast, ovarian, gastrointestinal, and colorectal cancers, typically also elevate CEA in pleural fluid. In contrast, malignancies that do not secrete CEA, including mesothelioma, lymphoma, leukemia, and melanoma, have low concentrations of CEA in pleural fluid comparable to concentrations observed in non-malignant effusions.
Elevated CEA concentrations in pleural fluid have also been reported with certain nonmalignant conditions, including liver cirrhosis, pancreatitis, complicated parapneumonic effusions and empyemas, and rarely with tuberculosis.
CEA results should be used in conjunction with cytological analysis of pleural fluid, imaging studies, and other clinical findings.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
An interpretive report will be provided.
A pleural fluid carcinoembryonic antigen (CEA) concentration of > or =3.5 ng/mL is suspicious but not diagnostic of a malignant source of the effusion. This cutoff yielded a sensitivity of 52%, specificity of 95%, and part per volume of 93% in a study of 200 patients presenting with effusion. CEA concentrations were significantly higher in effusions caused by CEA-secreting malignancies, including lung, breast, ovarian, gastrointestinal, and colorectal cancers. However, effusions caused by non-CEA-secreting malignancies, including lymphoma, mesothelioma, leukemia, and melanoma, routinely had CEA concentrations <3.5 ng/mL. Therefore, negative results should be interpreted with caution, especially in patients who have or are suspected of having a non-CEA-secreting malignancy.
Correlation of all tumor marker results with cytology and imaging is highly recommended.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
This test result should not be the sole basis for diagnosis. Carcinoembryonic antigen (CEA) and other tumor markers are not specific for malignancy and CEA testing has limited utility when used as the sole diagnostic test. Test results should be always correlated with cytology, imaging, and other clinical findings.
A low or negative CEA result may be misleading, as certain malignancies do not secrete CEA and will not produce elevated CEA concentrations in pleural effusions. Negative results should be interpreted with caution in patients who have or are suspected of having a non-CEA-secreting malignancy or who have a cancer of unknown primary origin. Alternative methodologies, including cytology, imaging, and other tumor markers should be considered.
CEA concentrations have been reported to be elevated in pleural fluid as a consequence of certain nonmalignant conditions, including liver cirrhosis, pancreatitis, complicated parapneumonic effusions and empyemas, and rarely with tuberculosis. Results should be interpreted with caution in patients with those conditions.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Shitrit D, Zingerman B, Shitrit AB, et al: Diagnostic value of CYFRA 21-1, CEA, CA 19-9, CA 15-3, and CA 125 assays in pleural effusions: analysis of 116 cases and review of the literature. Oncologist 2005;10:501-507
2. Hackbarth JS, Murata K, Reilly W, Algeciras-Schimnich A: Performance of CEA and CA19-9 in identifying pleural effusions caused by specific malignancies. Clin Biochem 2010 Sep;43(13-14):1051-1055
3. Garcia-Pachon E, Padilla-Navas I, Dosda MD, Miralles-Llopis A: Elevated level of carcinoembryonic antigen in nonmalignant pleural effusions. Chest 1997;111:643-647