Hepatocellular carcinoma, or malignant tumors of the liver, can be divided into two categories: primary and secondary. Primary liver malignancies originate from the liver. Secondary or metastatic hepatocellular carcinoma refers to malignant tumors originating from multiple organs throughout the body that invade the liver. It is usually seen in liver metastasis of malignant tumors of stomach, biliary tract, pancreas, colorectum, ovary, uterus, lung, breast and other organs.
1.Etiology
The etiology and exact molecular mechanism of primary hepatocellular carcinoma are not fully understood, and it is believed that its pathogenesis is a multifactorial and multi-step complex process, which is influenced by both environmental and consequential factors. Epidemiological and experimental research data show that hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, aflatoxin, drinking water contamination, alcohol, cirrhosis, sex hormones, nitrosamines and trace elements are all related to the development of hepatocellular carcinoma. Secondary hepatocellular carcinoma (metastatic hepatocellular carcinoma) can form disease through different ways, such as metastasis with blood or lymphatic fluid or direct infiltration into the liver.
2.Clinical manifestations
Primary liver cancer
(1) Symptoms: Early stage liver cancer often has no specific symptoms, while the symptoms of middle and late stage liver cancer have more symptoms. Some patients have low fever, jaundice, diarrhea, upper gastrointestinal bleeding, acute abdominal symptoms after rupture of hepatocellular carcinoma.
(2) Signs: Early stage liver cancer often has no obvious positive signs or only resembles the signs of cirrhosis. In middle and late stage liver cancer, signs such as liver enlargement, jaundice and ascites usually appear. In addition, those with combined cirrhosis often have liver palm, spider nevus, enlarged male breast, lower limb edema, etc. When extrahepatic metastasis occurs, the corresponding signs of each metastatic site may appear.
(3) Complications: common ones include upper gastrointestinal bleeding, hepatocellular carcinoma rupture and bleeding, liver and kidney failure, etc.
Secondary hepatocellular carcinoma
(1) Clinical manifestations of secondary hepatocellular carcinoma: Patients mostly complain of dullness and discomfort or vague pain in epigastric region or liver area. During physical examination, enlarged liver or hard nodules with firm texture and tenderness can be found in the middle and upper abdomen. The clinical manifestations of these patients are similar to primary liver cancer, but the development is usually relatively slow and mild. Metastasis may be suspected during various liver examinations, and the primary tumor is found during further examinations or surgical exploration. In some patients, the primary cancer foci cannot be found through various examinations.
(2) Symptoms caused by the primary tumor: For example, liver metastasis of colon and rectal cancer may be accompanied by changes in bowel habits, stool properties and blood in stool.
Laboratory tests
Laboratory tests for primary liver cancer
(1) Serum markers for liver cancer
(1) Serum alpha-fetoprotein (AFP) measurement: it has relative specificity for the diagnosis of this disease. The diagnosis of hepatocellular carcinoma can be considered when continuous serum AFP≥400μg/L is measured by radioimmunoassay and pregnancy and active liver disease can be excluded. Clinically, about 30% of patients with hepatocellular carcinoma are negative for AFP. If AFP heterogeneous body is detected at the same time, the positive rate can be significantly increased.
②Blood enzymology and other tumor markers: γ-glutamyl transpeptidase and its isoenzymes, abnormal prothrombin, alkaline phosphatase and lactate dehydrogenase isoenzymes in serum of patients with hepatocellular carcinoma may be higher than normal. However, they lack specificity.
(2) Imaging examination
(1) Ultrasonography: It can show the size, shape and location of the tumor, as well as the presence of cancer thrombus in the hepatic vein or portal vein, and its diagnostic rate can reach 90%.
②CT examination: with high resolution, the diagnostic rate of liver cancer can reach more than 90%, and can detect microscopic cancer foci with diameter of about 1 or 0 cm.
③MRI examination: the diagnostic value is similar to CT, and the differentiation of benign and malignant intrahepatic occupying lesions, especially with hemangioma, is better than CT.
④Selective abdominal artery or hepatic artery angiography: for carcinoma with abundant blood vessels, the low limit of resolution is about 1cm, for <2, 0cm<
span=””>small hepatocellular carcinoma, its positive rate can reach 90%.
⑤ Needle aspiration cytology by liver aspiration is performed under B-type ultrasound guidance with fine needle aspiration, which helps to improve the positive rate.
Secondary hepatocellular carcinoma
Most patients with secondary hepatocellular carcinoma have tumor markers within the normal range, but a small number of hepatic metastases from the stomach, esophagus, pancreas and ovaries may have elevated AFP. Most symptomatic patients have elevated ALP and GGT. Elevated carcinoembryonic antigen CEA is helpful for the diagnosis of liver metastases, and the positive rate of CEA in liver metastases of colorectal cancer is as high as 60%-70%. Selective hepatic angiography can detect lesions of 1 cm in diameter. Selective abdominal or hepatic arteriography mostly shows oligovascular type tumor; CT shows mixed inhomogeneous isointense or hypointense occupancy, typically presenting “
3.Diagnosis
According to the cause, clinical manifestations and examination results, clear diagnosis is made for different cases.
4.Treatment
Individualized and comprehensive treatment according to different stages of liver cancer is the key to improve the efficacy; treatment methods include surgery, hepatic artery ligation, hepatic artery chemoembolization, radiofrequency, freezing, laser, microwave, chemotherapy and radiotherapy. Biological treatment and traditional Chinese medicine are also used to treat liver cancer.
(1) Surgical treatment
Surgery is the first choice and the most effective method to treat liver cancer. Surgical methods include: radical hepatectomy, palliative hepatectomy and so on.
For hepatocellular carcinoma that cannot be resected, intraoperative hepatic artery ligation, hepatic artery chemoembolization, radiofrequency, freezing, laser, microwave and other treatments can be used according to specific conditions with certain efficacy. Primary hepatocellular carcinoma is also one of the indications for liver transplantation.
(2) Chemotherapy
If the cancer is found to be unresectable through abdominal dissection or as a follow-up treatment for palliative resection, regional chemoembolization by hepatic artery and/or portal vein pump (subcutaneous buried perfusion device) can be used; for those who are estimated to be unresectable through surgery, radiointerventional treatment is also feasible. Some patients may have the opportunity to have surgical resection.
(3) Radiation therapy
For patients with good general condition, good liver function, no cirrhosis, no jaundice, no ascites, no hypersplenism and no esophageal varices, limited cancer, no distant metastasis and not suitable for surgical resection or recurrence after surgery, radiation-based comprehensive treatment can be adopted.
(4) Biological therapy
Immunoribonucleic acid, interferon, interleukin-2, thymidine, etc. are commonly used, which can be combined with chemotherapy.
(5) Traditional Chinese medicine treatment
It is often used in combination with other therapies. To improve the body’s resistance to disease, improve the general condition and symptoms, and reduce the adverse effects of chemotherapy and radiotherapy. The “bull’s eye” sign; MRI examination of liver metastases often shows uniform signal intensity, clear sides and multiple occurrences, and a few have “target” sign or “bright ring” sign.