Hepatocellular carcinoma, i.e. malignant tumor of liver, can be divided into two categories: primary and secondary. Primary liver malignant tumors originate from epithelial or mesenchymal tissues of the liver, and the former is called primary liver cancer, which is a highly prevalent and dangerous malignant tumor in China; the latter is called sarcoma, which is less common compared with primary liver cancer. Secondary or metastatic hepatocellular carcinoma refers to the invasion of malignant tumors from multiple organs of the body to the liver. It is usually seen in liver metastases from malignant tumors of stomach, biliary tract, pancreas, colorectum, ovary, uterus, lung, breast and other organs.
Etiology
The etiology and exact molecular mechanism of primary hepatocellular carcinoma are not fully understood, and it is believed that its development is a multifactorial and multi-step complex process, which is influenced by both environmental and consequent factors. Epidemiological and experimental research data indicate 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 associated with the development of liver cancer. Secondary hepatocellular carcinoma (metastatic hepatocellular carcinoma) can form disease through different pathways, such as metastasis with blood or lymphatic fluid or direct infiltration of the liver.
Clinical manifestations
1.Primary hepatocellular carcinoma
(1) Symptoms
The common clinical manifestations include pain in liver area, abdominal distension, poor appetite, weakness, emaciation, progressive liver size or upper abdominal mass, etc. Some patients have low fever, jaundice, diarrhea, upper gastrointestinal bleeding, and acute abdominal symptoms after rupture of liver cancer. There are also symptoms that are not obvious or only manifest as metastatic foci.
(2) Physical signs
Early stage hepatocellular carcinoma 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, liver palms, spider nevus, enlarged male breast and edema of lower limbs are often seen in combined cirrhosis. When extrahepatic metastasis occurs, signs corresponding to each metastatic site may appear.
(3) Complications
The common ones include upper gastrointestinal bleeding, hepatocellular carcinoma rupture and bleeding, liver and kidney failure, etc.
2.Secondary liver cancer
(1) Clinical manifestations of primary tumor
It is mainly seen in patients without history of liver disease, and liver metastasis is still in early stage without corresponding symptoms, while the symptoms of primary tumor are mostly in middle and late stage. Secondary hepatocellular carcinoma in such patients is mostly found during the examination and follow-up of primary treatment.
(2) Clinical manifestations of secondary hepatocellular carcinoma
Patients mostly complain of dullness and discomfort or vague pain in upper abdomen or liver area, and with the development of the disease, they will experience weakness, poor appetite, emaciation or fever. 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.
(3) Clinical manifestations of both primary tumor and secondary liver cancer
In addition to the symptoms and signs similar to those of primary liver cancer, patients also have clinical manifestations caused by 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.
Examination
1.Laboratory examination of primary liver cancer
(1) Liver cancer serum marker test
(1) Serum alpha-fetoprotein (AFP) measurement
It has relative specificity for the diagnosis of the 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 examination
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
①Ultrasound examination
It can show the size, shape and location of the tumor, as well as the presence of cancer clots 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 over 90%, and can detect microscopic cancer foci of 25px in diameter.
③MRI examination
The diagnostic value is similar to CT, and it is better than CT in differentiating benign and malignant intrahepatic occupying lesions, especially with hemangioma.
④Selective abdominal artery or hepatic artery angiography
For carcinomas with abundant blood vessels, the low resolution limit is about 25px, and the positive rate for small hepatocellular carcinomas <50px< span=""> can reach 90%.
⑤ Needle aspiration cytology by liver aspiration
Fine needle aspiration under the guidance of B-type ultrasound can help to improve the positive rate.
2.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 25px in diameter. Selective abdominal or hepatic arteriography mostly shows less vascular tumors; CT shows mixed inhomogeneous isointense or hypointense occupancy, typically showing “bull’s eye” sign; MRI examination of liver metastases often shows uniform signal intensity, clear sides and multiple lesions, and a few have “target” sign or “bright ring” sign. MRI often shows homogeneous signal intensity, clear edges and multiple occurrences, and a few of them have “target” sign or “bright ring” sign.
Diagnosis
Based on the causes of development, clinical manifestations and examination results, a clear diagnosis is made for different cases.
Treatment
Individualized and comprehensive treatment according to different stages of liver cancer as appropriate is the key to improve the efficacy; treatment methods include surgery, hepatic artery ligation, hepatic artery chemoembolization, radiofrequency, freezing, laser, microwave, as well as 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, etc.
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 and have certain therapeutic effects. Primary hepatocellular carcinoma is also one of the indications for liver transplantation.
2.Chemical drug treatment
If the cancer is found to be unresectable by dissection or as a follow-up treatment of palliative resection, regional chemoembolization by hepatic artery and/or portal vein placement pump (subcutaneous buried perfusion device) can be used; for those who are estimated to be unresectable by surgery, radiointerventional treatment is also feasible, such as selective cannulation through femoral artery to hepatic artery, injection of embolic agent (commonly used such as iodized oil) and anticancer drugs for chemoembolization, and some patients can thus Some patients may have the chance 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 treatment
Immunoribonucleic acid, interferon, interleukin-2, thymidine, etc. are commonly used, which can be combined with chemotherapy.
5.Chinese herbal medicine treatment
It is often used in combination with other therapies. It can improve the body’s resistance to disease, improve the general condition and symptoms, and reduce the adverse effects of chemotherapy and radiotherapy.
Therefore, it is especially important to have annual routine health checkups, especially for high-risk groups with history of hepatitis B. Early detection of lesions and early comprehensive treatment mainly with surgery when the tumor is small and has not invaded large blood vessels can achieve more satisfactory prognosis.