Liver cancer is the 4th most common cancer among men and the 11th most common cancer among women in Hong Kong. According to the Hong Kong Cancer Registry of the Hospital Authority, there were 1876 new cases in 2019, with 1448 cases in men and 428 cases in women, a male to female ratio of about 3.4 to 1. Before the age of 75 years, the cumulative risk of liver cancer is 1 in 40 for men and 1 in 181 for women. The median age of diagnosis is 66 for men and 71 for women.
Rapid declining age-standardized incidence was observed in liver cancer. On average of the previous 10 years, there has been a decrease per year in the age-standardized incidence by 2.3% in males and 4.8% in females.
There are two types of adult primary liver cancer, namely hepatocellular carcinoma (HCC) and bile duct cancer (cholangiocarcinoma). The most common type of adult primary liver cancer is hepatocellular carcinoma.
Known causes of liver cancer include:
- Hepatitis B or C infection
- Long-term alcoholism
- Consumption of food contaminated by aflatoxins
- Ingestion of oral contraceptives that contain certain ingredients
- Ulcerative colitis (UC)
- Liver fluke
- Consumption of food containing toxins
- Long-term exposure to certain environments or pollutants
- Cholangitis or choledochal cysts
Symptoms may not be apparent during the early stages of liver cancer. As the tumour grows larger, patients may experience the following symptoms:
- Loss of appetite and significant weight loss
- Upper abdominal and right shoulder pain
- Upper abdominal pain, discomfort, or lumps
- Jaundice, yellowing of the skin and eyes
- Tea-colored urine, clay-colored stools
- Ascites (accumulation of fluid in the abdominal cavity)
However, these symptoms are not unique to liver cancer. If the above symptoms appear, there is no need to worry too much but medical attention should be sought as soon as possible so that any necessary diagnostic procedures and treatments may be started early to prevent disease progression.
People with a high risk of developing liver cancer should undergo regular medical examinations. They include elderly men and patients with chronic liver disease. Tests for liver cancer include:
- Liver ultrasound scan
- Alpha-fetoprotein (AFP) blood test
- Computed tomography (CT) scan
- Magnetic resonance imaging (MRI)
- Liver biopsy
- Indocyanine green (ICG) clearance test
Among the tests, the preoperative indocyanine green (ICG) clearance test is especially important for liver cancer surgery. This test is mainly used to assess the detoxification and metabolic function of the liver, which allows doctors to accurately evaluate the condition of the liver and assess the risk of the surgery.
Treatment for liver cancer depends on the patient’s condition, which is determined based on the type, size, location, and degree of metastasis of the tumour, as well as the patient’s age and physical condition.
Surgery aims to cure cancer by removing the tumour and part of the liver. In the past, laparotomy (i.e. the traditional method) was the surgical method of choice, but nowadays, minimally invasive procedures for liver cancer resection have become very popular. Procedures such as laparoscopy, robotic surgery, and radiofrequency ablation can help reduce complications that arise from surgical wounds. Patient undergoing these procedures may be discharged from the hospital as early as two to three days after surgery.
The entire liver is removed and replaced with a healthy donated liver. It may be done when the disease is in the liver only and a donated liver can be found. If the patient has to wait for a donated liver, other treatment is given as needed.
Ablation therapy removes or destroys tissue. Different types of ablation therapy are used for liver cancer:
- Radiofrequency ablation
- Microwave therapy
- Percutaneous ethanol injection
- Electroporation therapy
Embolization therapy is the use of substances to block or decrease the flow of blood through the hepatic artery to the tumor. When the tumor does not get the oxygen and nutrients it needs, it will not continue to grow.
There are three main types of embolization therapy:
- Transarterial embolization (TAE): A small incision (cut) is made in the inner thigh and a catheter (thin, flexible tube) is inserted and threaded up into the hepatic artery. Once the catheter is in place, a substance that blocks the hepatic artery and stops blood flow to the tumor is injected.
- Transarterial chemoembolization (TACE): This procedure is like TAE except an anticancer drug is also given.
- Radioembolization — Radioembolization using intraarterial injection of 90-Y-labeled microspheres induces extensive tumor necrosis with an acceptable safety profile.
Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells. Targeted therapies usually cause less harm to normal cells than chemotherapy or radiation therapy do. Tyrosine kinase inhibitors are a type of targeted therapy used in the treatment of adult primary liver cancer. Sorafenib, lenvatinib, regorafenib, and cabozantinib are types of tyrosine kinase inhibitors used to treat advanced liver cancer.
Immunotherapy is a treatment that uses the patient's immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body's natural defenses against cancer. Immune checkpoint inhibitor therapy is the type of immunotherapy commonly used to treat advanced or recurrent liver cancer.
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy:
- External radiation therapy uses a machine outside the body to send radiation toward the area of the body with cancer.
- Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer.