1. Introduction to Alpha-Fetoprotein (AFP)

What is Alpha-Fetoprotein (AFP)? Alpha-Fetoprotein (AFP) is a glycoprotein produced primarily by the fetal liver and yolk sac during pregnancy. In adults, AFP levels are typically low, but elevated levels can indicate certain cancers (e.g., hepatocellular carcinoma, germ cell tumors) or liver diseases. During pregnancy, AFP is measured in maternal serum or amniotic fluid to screen for fetal abnormalities, such as neural tube defects or Down syndrome. Measuring AFP levels in blood is used for both oncologic and prenatal diagnostic purposes.

2. What is an AFP Unit Converter?

Definition: The Alpha-Fetoprotein Unit Converter converts AFP concentrations between various units, enabling standardization of laboratory results for clinical use.

Purpose: It assists clinicians and researchers in interpreting AFP levels across different measurement units (e.g., IU/mL to ng/mL), ensuring accurate diagnosis and monitoring of cancers, liver diseases, and fetal conditions.

3. Importance of AFP Unit Conversions

Converting AFP concentrations between units is critical for:

• Standardizing Results: Different labs report AFP in various units (e.g., IU/mL, ng/mL); conversion ensures consistency for diagnosis and monitoring.
• Clinical Diagnosis: Accurate conversions aid in diagnosing hepatocellular carcinoma, germ cell tumors, liver diseases, and prenatal screening for fetal abnormalities.
• Research and Collaboration: Enables comparison of AFP data across studies or institutions using different measurement standards.

4. Clinical Significance

Elevated Levels: In non-pregnant adults, high AFP levels may indicate hepatocellular carcinoma, germ cell tumors (e.g., testicular cancer), or liver diseases (e.g., hepatitis, cirrhosis). In pregnancy, elevated maternal AFP can suggest neural tube defects (e.g., spina bifida), while low levels may indicate Down syndrome or other chromosomal abnormalities.

Normal Levels: In non-pregnant adults, AFP levels are typically very low. During pregnancy, normal AFP levels vary by gestational age and are reported as multiples of the median (MoM).

Normal Ranges:

• Non-pregnant adults: Typically < 10 ng/mL (< 10 µg/L or < 8.3 IU/mL).
• Pregnancy: Varies by gestational week (e.g., 15–50 ng/mL at 15–20 weeks); reported as MoM (0.5–2.5 MoM is typical).
• Values vary by lab, assay, and clinical context—consult a healthcare provider for interpretation.

5. Precautions

Interferences:

• AFP levels in pregnancy must be interpreted with gestational age, maternal weight, and other factors (e.g., multiple pregnancies).
• Non-cancerous conditions (e.g., hepatitis, cirrhosis) can elevate AFP, requiring differentiation from malignancy.
• Interpret AFP levels with imaging, other tumor markers (e.g., hCG, CEA), and clinical findings—consult a healthcare provider for accuracy.

6. Frequently Asked Questions (FAQ)

Q: Why are there different units for AFP?
A: Different units reflect varying standards; IU/mL is used for international standardization, while ng/mL and µg/L are common in clinical practice, particularly in oncology and prenatal screening.

Q: What is a normal AFP level?
A: Normal AFP in non-pregnant adults is typically < 10 ng/mL (< 10 µg/L or < 8.3 IU/mL). In pregnancy, levels depend on gestational age and are reported as MoM. Consult a healthcare provider for interpretation.

Q: Can this converter be used for other tumor markers?
A: No, this converter is specific to AFP; other tumor markers (e.g., hCG, CA-125) have different units and conversion factors—consult a healthcare provider for accuracy.