The Alpha-Fetoprotein (AFP) test is a blood test that measures the levels of AFP in the blood. AFP is a protein produced by the developing fetus during pregnancy, and is also produced in small amounts by some adult tissues, particularly the liver. The AFP test is commonly used as a screening tool for certain types of cancer, particularly liver cancer and testicular cancer, as well as to monitor the progression of these cancers and evaluate the effectiveness of treatment. Elevated levels of AFP in the blood can indicate the presence of cancer, while low levels are typically not of concern. The AFP test involves taking a small sample of blood, which is then analyzed in a laboratory to determine the levels of the protein. Depending on the results of the test, doctors may recommend additional diagnostic tests or treatments to address underlying conditions. Regular monitoring of AFP levels can also be used to track the progression of cancer and evaluate the effectiveness of treatment.