A 40-year-old male patient with a 10-year history of hepatitis B who had never undergone antiviral treatment, suffered from severe liver damage induced by several days of exertion due to house renovation in early August this year, with total bilirubin (jaundice) reaching 80 μmol/L and rising above 200 μmol/L two weeks later, transaminase 751 IU/L, albumin dropping to 27 g/L, and methemoglobin rising from 600 μg/L to 1000 μg/L and then above 2000 μg/L. The patient, who was still happy and full of confidence, became preoccupied and had difficulty sleeping for several days after listening to the words of the patient, worrying about the highly malignant liver tumor he had gotten. Is this patient suffering from malignant tumor? What is the meaning of elevated alpha fetoprotein? Why is his alpha-fetoprotein so high? Alpha-fetoprotein (AFP) is a glycoprotein, which is a single polypeptide chain consisting of 590 amino acid residues. It is physiologically present in low concentrations in adults (<20 μg/L). Methemoglobin is synthesized by hepatocytes during embryonic life and is present in very small amounts in adults. The synthesis of AFP increases when hepatocellular carcinoma occurs, and 90% of hepatocellular carcinomas can be detected early by AFP screening. In addition, AFP is also significantly elevated in some tumors outside the liver. So does elevated AFP necessarily mean the development of liver tumors or tumors in other areas? The answer is no, because more than 20% of hepatitis B patients also have abnormal AFP. The serum AFP level can be low or moderately elevated during the course of hepatitis B. However, in patients with active hepatitis, the regeneration of hepatocytes is active and their AFP concentration increases more; along with the repair of the liver and regeneration of hepatocytes, it decreases as the disease gets better. After careful screening of multiple tumor indicators, it was confirmed that this patient's elevated AFP was closely related to the disease attack. After active treatment, the patient's condition gradually improved and AFP was slowly decreasing, so the patient finally put down his heart that had been hanging for days. Therefore, when the AFP is elevated on the laboratory test, you should ask your doctor in time to find out the hidden factors in your body, and follow up regularly to exclude other causes, so that a healthy and high quality life is always with you.