Understanding the Alpha-Fetoprotein (AFP) Blood Test
Being advised to have an Alpha-Fetoprotein (AFP) blood test can raise many questions. In my practice, I explain that AFP is a tumour marker that provides useful clinical information in specific situations, but it is not used to diagnose cancer on its own.
AFP is most commonly used alongside imaging studies and other investigations when monitoring certain liver conditions or specific cancers.
What Is AFP?
Alpha-Fetoprotein (AFP) is a protein produced naturally during fetal development. In healthy adults, AFP levels are usually very low.
An AFP blood test measures the amount of this protein in your bloodstream.
Why Might Your Doctor Recommend an AFP Test?
Your doctor may request an AFP test to:
- Monitor individuals with chronic liver disease who are at increased risk of liver cancer
- Assist in the assessment of liver masses alongside imaging studies
- Monitor treatment response in certain cancers
- Detect recurrence after treatment for selected cancers
- Evaluate specific germ cell tumours when clinically appropriate
AFP is not recommended as a routine cancer screening test for healthy individuals without risk factors.
What Can Cause an Elevated AFP Level?
Higher AFP levels may be seen in:
- Hepatocellular carcinoma (primary liver cancer)
- Certain germ cell tumours
- Chronic hepatitis
- Liver cirrhosis
- Active liver inflammation
- Pregnancy
An elevated AFP level alone does not confirm a diagnosis of cancer.
Can AFP Diagnose Liver Cancer?
No.
Although AFP may be elevated in some patients with liver cancer, many other liver conditions can also increase AFP levels. Likewise, some patients with liver cancer may have normal AFP levels.
For this reason, AFP is interpreted together with your symptoms, medical history, imaging studies such as ultrasound, CT or MRI, and other laboratory investigations.
Who May Benefit from AFP Monitoring?
AFP testing may be recommended for individuals who:
- Have chronic hepatitis B or hepatitis C
- Have liver cirrhosis
- Are being monitored after treatment for liver cancer
- Have been diagnosed with certain germ cell tumours
- Are advised by their specialist to undergo tumour marker monitoring
When Should You See a Doctor?
Seek medical advice if you experience:
- Persistent abdominal discomfort
- Unexplained weight loss
- Yellowing of the skin or eyes
- Loss of appetite
- Ongoing fatigue
- Known chronic liver disease requiring regular follow-up
Regular monitoring allows your doctor to detect changes early and determine whether further investigations are required.
Doctor's Insight
In my practice, I remind patients that AFP is just one part of the overall assessment. While it can provide valuable information in selected clinical situations, it should never be interpreted in isolation. Appropriate use of AFP, together with imaging and clinical evaluation, helps us make informed decisions about diagnosis, monitoring and ongoing care.
– Dr. Teh Boon Teong
Consultant in Internal Medicine
Evercare Medical Care Centre, Penang, Malaysia.
Frequently Asked Questions
It measures the level of Alpha-Fetoprotein, a protein that may be elevated in certain liver diseases and some cancers.
No. AFP alone cannot diagnose liver cancer and must be interpreted together with imaging and other clinical findings.
It is commonly used to monitor chronic liver disease, evaluate liver abnormalities or follow up after treatment for certain cancers.
Yes. Chronic hepatitis, liver cirrhosis and pregnancy are among the conditions that may cause elevated AFP levels.
AFP is generally reserved for people with specific medical conditions or risk factors and is not recommended as a routine screening test for the general population.