Liver Cancer: The epithelial cells of the liver are responsible for the constitution of the liver tissue. In their normal state, these cells grow and divide into new cells, which are formed as needed, this process is called cell regeneration.
When normal cells age or are damaged, they die naturally. When cells lose this control mechanism and undergo changes in their genome (DNA) they become cancer cells. They do not die when they age or get damaged and produce new cells, which are not necessary, in an uncontrolled way and giving rise to cancer.
Unlike normal cells, liver cancer cells do not respect the organ’s borders, invading the surrounding tissues or spreading to other parts of the body. This process is called metastization.
There are several types of liver cancer:
Primary liver cancer – cancer of the liver, uncommon;
Metastatic or secondary cancer – cancer that has spread or spread to the liver, but that originated in other organs.
Primary liver cancers may be of various subtypes:
Hepatocellular carcinoma (hepatoma or hepatocarcinoma) – These cancers originate from epithelial cells that form the liver. Hepatocellular carcinoma is the most common liver tumor in adults. Hepatoblastoma – These pediatric tumors originate from embryonic liver cells;
Sarcomas of the liver – These are very rare tumors that originate in cells of the liver that are not epithelial, they can be vessels, muscle or supporting tissues.
Any behavior or condition that increases your risk of having an illness is a risk factor. If one or more risk factors apply to you, it does not mean that you will necessarily develop liver cancer. Similarly, liver cancer may appear in individuals who do not have known risk factors.
The causes for liver cancer have not yet been found, but some risk factors are known. The main risk factors are:
- Infection with hepatitis B or C virus;
- Family history – have a close relative with hepatitis B virus infection and liver cancer;
- Cirrhosis, which can be caused by abusive alcohol consumption;
- Consumption of food colonized by aflatoxin, a substance produced by a fungus that can grow in foods such as legumes and nuts that have not been properly stored.
In a patient with cynical history and clinical examination suspected of liver cancer, general blood tests should be ordered, including evaluation of liver function and a tumor marker called alpha fetoprotein . Imaging tests may be done which may include ultrasound, CT scan, and MRI .
The doctor can perform a biopsy of the tissues, that is, harvest a liver cell for microscopic analysis.Liver biopsy can be performed by inserting a thin needle through the skin into the organ, guided by CAT or ultrasound. Alternatively, a laparoscopic procedure can be performed, in which the surgeon inserts through a small incision into the abdomen an equipment – a laparoscope – that contains a tool to remove part of the liver tissue
It is only when observed under the microscope that biopsied material from the liver mass is suspected that the diagnosis of liver cancer can be confirmed.
SIGNALS AND SYMPTONS
The signs and symptoms of liver cancer often only appear in more advanced stages of the disease, but sometimes they may appear earlier. If you see your doctor at first symptoms, the cancer can be diagnosed earlier and the treatment is started, while it is still more likely to be helpful.
Signs and symptoms of liver cancer may include:
• Weight loss.
• Lack of appetite.
• Feeling of fullness in the upper abdomen after a light meal.
• Increased liver.
• Increased spleen.
• Abdominal pain.
• Swelling or accumulation of fluid in the abdomen.
• Jaundice (yellowish skin and mucous membranes).
• Belly veins dilated and visible through the skin.
• Aggravation of chronic hepatitis or cirrhosis.
Some liver tumors produce hormones that act on organs other than the liver and can cause:
• Hypercalcaemia (Increased calcium in the blood).
• Hypoglycaemia (Decreased blood sugar).
• Gynecomastia (breast enlargement in men).
• Erythrocytosis (increased red blood cells).
• High cholesterol levels.
These symptoms are also related to other diseases, are not necessarily signs and symptoms unique to liver cancer. However, if any of these symptoms are present, a physician should be consulted for accurate diagnosis and initiation of treatment if necessary.
Given the state of liver cancer, the multidisciplinary clinical team will evaluate the best treatment to follow.
This may include surgery, radiotherapy, and systemic therapy.
– Localized operable disease – usually treated by surgery;
– Locally advanced disease – treatment options include performing transplant surgery or other local techniques, radiotherapy and systemic therapy;
– Disseminated disease – treatment options include systemic therapy and eventually radiation therapy.
The surgical procedure for liver cancer gives the name of hepatectomy and consists of an abdominal surgery that can be of two natures:
– Partial hepatectomy – This surgery removes part of the liver that has the cancer;
– Total hepatectomy – In this surgery the whole liver is removed and the liver of a donor has to be transplanted.
In this surgery samples should also be taken from the lymph nodes.
There are other local techniques used to treat liver cancer performed by surgeons, interventional radiologists or radiotherapists:
Radiofrequency ablation – a procedure that involves the introduction of a probe containing small electrodes, to destroy the cancer cells through heat. Usually the doctor introduces the catheter through the skin, using local anesthesia and it may be necessary to use an ultrasound, MRI or CT scan to guide the catheter to the tumor;
– Cryosurgery – procedure consisting of the introduction of a probe to destroy the cancer cells through the cold;
– Injection of ethanol into the lesion – the doctor introduces a thin needle guided by ultrasound, injecting alcohol (ethanol) directly into the tumor and destroying the cancer cells. Usually the needle is introduced by local anesthesia, however if the patient has several liver cancer, general anesthesia may be required;
– Embolization – This procedure involves the introduction of a catheter into an artery of the leg to reach the artery of the liver. Through the catheter the doctor injects particles that block the flow of blood from the liver artery, causing the tumor to weaken. The liver continues to work normally once it receives blood from other vessels;
– Chemoembolization – This procedure is similar to embolization, and the doctor injects a chemotherapy drug before inserting the particles that block the blood flow from the liver artery.Without blood flow, the drug stays in the liver longer.
With regard to systemic therapy in liver cancer, classical chemotherapy is of little use and increasingly directed and biological therapies are being used, including the use of a substance called surafenib. This type of therapy slows tumor growth and reduces blood flow to it.