Alpha-fetoprotein (AFP)

Alpha-fetoprotein is a protein normally produced by the liver and yolk sac of a developing fetus. In adults, blood levels are usually very low, but they can rise in certain liver diseases and cancers, particularly hepatocellular carcinoma (liver cancer) and some germ cell tumors. Doctors measure AFP with a simple blood test and use it as a tumor marker to help screen for, diagnose, and monitor these conditions.

Origin

AFP was first identified in human fetal serum in 1956 by Swedish researcher Carl-Bertil Laurell, and its association with liver cancer was established in the 1960s by Russian scientist Garri Abelev. The name reflects its discovery as a fetal ("feto-") protein abundant in early life.

Significance in Asbestos Context

AFP is not a marker for mesothelioma or asbestos-related lung disease, but it sometimes appears on bloodwork ordered during a cancer workup. Patients being evaluated for an unexplained mass, abdominal symptoms, or ascites may have AFP checked alongside other tumor markers (such as CA-125, CEA, and mesothelin) to help distinguish peritoneal mesothelioma from liver cancer or metastatic disease, since these can look similar on imaging. A normal AFP helps argue against a primary liver cancer, supporting the workup toward mesothelioma or another diagnosis. Patients should ask their oncologist which tumor markers were drawn, what the results showed, and which diagnosis each marker pointed toward. These results often appear in pathology and oncology records that matter to a legal claim.

Example Sentence

When the patient's abdominal CT showed peritoneal thickening, her doctor ordered AFP and CA-125 to help rule out hepatocellular carcinoma before confirming peritoneal mesothelioma by biopsy.

Related Terms

Tumor Marker, Mesothelin, CA-125, Peritoneal Mesothelioma, CEA, Differential Diagnosis

Notes

• Ask your oncologist for a copy of every tumor marker panel drawn during your workup and keep them with your medical records. They document how other cancers were ruled out.
• A normal AFP does not rule out mesothelioma, and an elevated AFP does not confirm any single diagnosis; interpretation depends on imaging, biopsy, and the full clinical picture.
• If you have a history of hepatitis B, hepatitis C, or cirrhosis in addition to asbestos exposure, tell your doctor. AFP can be elevated from liver disease unrelated to your asbestos history.
• Request that the differential diagnosis (the list of conditions your doctors considered and excluded) be documented in writing, as this can be important evidence that your cancer was correctly identified as asbestos-related.