Methemoglobin quantification is the measurement of the specific value of methemoglobin, which, if elevated, often indicates a pathological condition in the body. Alpha-fetoprotein is a glycoprotein that is mainly present in the fetal circulation, but is gradually replaced by albumin 2-3 months after birth, and its concentration decreases and disappears. In adults, elevated levels of alpha fetoprotein are usually caused by abnormalities. Abnormal factors are used to screen for the presence of primary liver cancer, to determine the prognosis of liver cancer, to monitor the effectiveness of treatment and as a tumor marker for tumor recurrence. Primary liver cancer can be diagnosed if the drawn blood value is greater than 400ng/mL for more than one month, combined with ultrasound, CT or MRI, which reveals the presence of occupying lesions in the liver. Primary liver cancer can also be diagnosed if it is greater than 200ng/mL and lasts for more than two months. Some patients with hepatobiliary diseases, such as acute hepatitis, liver failure, and cirrhosis, may also have elevated methemoglobin. Precautions For patients with slightly elevated values, the magnitude of the elevated values should be closely monitored to understand the early changes of the disease in a timely manner. Therefore, comprehensive analysis and judgment are required when quantifying AFP, and regular rechecking of AFP values is required to prevent the risk of underdiagnosis of early lesions.