Liver Cancer
What is Liver Cancer?
Liver cancer can be categorised as primary (starts within the liver) or secondary cancer (starts elsewhere in the body and spreads to the liver - metastases).
Primary Liver Cancer
Primary liver cancer are cancers arising from within the liver and is a less common cancer of the liver. The most common primary liver cancers are hepatocellular carcinoma (HCC or hepatoma) and they originate from liver cells (hepatocytes). Rarely, the cancer can start from the bile ducts which are called cholangiocarcinoma.
Risk Factors for Primary Liver Cancer
The majority of people who develop HCC have an underlying chronic liver disease. This includes viral hepatitis (Hepatitis B or C), alcoholic cirrhosis, non-alcoholic fatty liver disease (NAFLD) or hereditary conditions such as haemochromatosis. However, only a small percentage of people with chronic liver disease will go on to develop HCC. Cholangiocarcinoma may develop in patients with chronic inflammation of their bile ducts, such as primary sclerosing cholangitis (PSC), or as a sporadic case.
Secondary Liver Cancer
The most common form of liver cancers are secondary liver cancers – These are cancers that start in a different part of the body and spreads (metastases) to the liver. There are a variety of cancers that can spread to the liver. These can be from within the abdominal cavity, such as bowel (colorectal), stomach, pancreas; or from outside the abdomen, such as melanoma or breast. These liver cancers are defined by the primary cancer, e.g. metastatic stomach cancer are cancers that has spread to the liver from the stomach. Occasionally, the diagnosis of the liver cancer is made before the detection of the primary cancer. The most commonly seen secondary liver cancer arises from colorectal origin.
Diagnosis of Liver Cancer
Liver cancer is hard to identify as they do not present with symptoms until the later stages. We rely on clinical (taking a thorough history and performing an examination), biochemical (blood tests) and radiological (such as ultrasound or CT) to guide us in the diagnosis of liver cancers. Rarely, we may need to obtain a tissue sample (pathology) to confirm the diagnosis.
Clinical
It is important to take a thorough history (particularly of any previous cancers or risk factors of liver disease) and an examination to identify potential signs of liver disease.
Blood tests
Routine blood tests are non-specific for diagnosing liver cancer. Liver enzymes can be normal in patients with liver cancer. Tumour markers (such as AFP, CA19-9 and CEA) may guide in the diagnosis of liver cancer and the type of liver cancer.
Radiology (Non-invasive)
Ultrasound
This involves placing an ultrasound probe on the skin and using sound waves, take images of the liver at different areas. This is painless.
CT (Computed tomography) scan
This is a specialised X-ray taken to build a 2-dimensional image of your body. It requires you to be able to lie still on a flat surface and the scanner moves up/down your body. You will be required to have an intravenous (IV) line inserted to administer contrast agent to help better image your liver.
Magnetic Resonance Imaging (MRI)
This is another specialised imaging test similar to a CT scan. Instead of using X-Rays, MRI uses magnetic force to construct a picture of your body. You will also require an IV line for a contrast agent, similar to CT scan.
Liver biopsy
Occasionally, a liver biopsy is recommended to confirm the diagnosis of liver cancer. This will be performed by a radiologist under local anaesthetic and can be done under USS or CT guidance. A small piece of liver tissue will be removed with a needle and sent for testing for cancer cells.
Laparoscopy
In rare occasions, we would recommend a laparoscopy to look at the liver within the abdomen. This involves a general anaesthetic and introduction of a laparoscope (telescope) into the abdominal cavity. This allows us to look at the liver directly and provide options to perform a number of procedures at the same setting including taking a sample of liver tissue, ablation of the lesion or liver surgery. The optimal procedure will be determined at the time of the operation.
Treatment of Liver Cancer
There are various treatment options and will rely on whether it is a primary or secondary cancer. Treatment will require input from specialists from different specialties in a multi-disciplinary format and options include surgery, ablation, chemotherapy +/- radiotherapy.
Surgery (Liver/hepatic resection)
This is the main treatment option for primary liver cancer. In secondary liver cancers, liver surgery is an option if the cancer is limited to the liver or in cases where there are other disease elsewhere in the body, that the other metastatic disease can be treated effectively.
The aim of liver surgery is to remove the cancer with the minimal amount of uninvolved liver tissue. The extent of the surgery is dependent on the distribution, number and size of the liver tumours. It can be performed through either open or laparoscopic (key-hole) surgery. The ideal approach will be discussed with you at your consultation and the priority is to be able to remove the liver cancers safely with a good outcome. There are occasions where more than one surgery are required to remove all the liver cancers. Liver surgery can also be combined with other procedures on the liver (such as ablation) or even surgery to other parts of the abdomen (such as bowel resection).
Ablation therapy
Ablation therapy is a procedure that destroy the tumour cells without removing them. It can be performed percutaneously (through the skin), with laparoscopic (keyhole) surgery or at laparotomy (open surgery). Ablation can be considered for small tumours (< 3 cm) or when surgery is not suitable or in combination with liver resection. There are different types of ablation:
Microwave Ablation (MWA)
MWA uses high intensity microwaves to heat and destroy the tumour. It uses a fine needle that are inserted through the skin or directly into the tumour (during laparotomy or laparoscopy) under ultrasound guidance. The main advantage of MWA is the potential to treat tumours close to blood vessels, and shorter time to reach thermal ablation.
Radiofrequency Ablation (RFA)
RFA uses high-energy radiowaves to produce thermal ablation. Similar to MWA, a fine needle is inserted into the tumour under ultrasound guidance. High-frequency current is passed through the tip of the needle, and heats the tumour destroying the cancer cells.
Chemotherapy
In certain cases, chemotherapy may be prescribed for liver cancer. In HCC, there is one agent that has been shown to be effective (Sorafenib) but it is not currently funded in New Zealand. For secondary liver cancer, the type of chemotherapy and dosing regimen depends on the original cancer type. The administration of the chemotherapy is managed by an oncologist in conjunction with Dr Michael Chu. If the original tumour is outside the liver, Dr Michael Chu will liaise with another surgical specialist to discuss management of the primary tumour.
Radiotherapy
Radiotherapy is rarely used in the treatment of liver cancers. A newer treatment, selective internal radiation therapy (SIRT) is occasionally used – Radioactive beads are injected directly into the tumour via the blood vessel supplying the tumour and this administers the radiotherapy directly in the tumour from within. This treats only the tumour within the liver without the side effects of systemic treatment. The indications for SIRT will be managed in a multidiscliplinary team.