Liver tumours can be benign (noncancerous) or malignant (cancerous). When cancer is detected in the liver, it can either arise from the liver itself (primary liver cancer), or spread from other parts of the body to the liver (secondary liver cancer). Common benign tumours/nodules in the liver are hemangioma (tumour of blood vessel origin), and Focal Nodular Hyperplasia (FNH), which is strictly speaking not a tumour but an overgrowth of normal liver cells.
Hepatocellular Carcinoma (HCC)
The most common primary liver cancer is Hepatocellular Carcinoma, which often arises from a person who is infected with Hepatitis B. Increasingly, HCC is also seen in patients who have liver cirrhosis secondary to Non- Alcohol Fatty Liver Disease (NAFLD). Cirrhosis from any other causes also places the liver at risk of developing HCC.
Very often, the cancer does not produce symptoms until it is quite large in size. Patients who are known to have Hepatitis B, or have liver cirrhosis will be on regular checkup for their condition. Hence the cancer may be picked up on the regular scans that are performed as part of the checkup.
Some patients may come to know that they have a tumour in the liver only when they go for a healthscreen and a tumour is detected on scans. When symptoms do arise, the common complaints are pain and discomfort in the upper abdominal region, poor appetite and feeling easily tired, or jaundice.
When a liver tumour is seen on an ultrasound scan, a CT scan or an MRI is done to further assess the nature and extent of the tumour. Blood investigations will be done to ascertain the function of the liver. Alpha-feto protein level which is a cancer marker for HCC will be carried out with a blood test, as well as blood tests for the presence of chronic viral Hepatitis B and C.
Unlike many other cancers where spread of cancer cells beyond the organ is commonly seen, HCC is often confined to the liver only. However, the treatment for HCC is influenced by the size of the cancer, the number of cancer nodules, whether the cancer has involved the blood vessels of the liver and also the status of the liver in which the cancer arises. HCC often occurs in the liver that is cirrhotic (hardened), and that can impact on the treatment. Hardening of the liver is due to the presence of chronic Hepatitis B or C, or due to other insults to the liver such as alcohol or inflammation due to fat in the liver. Treatment options can be broadly divided into surgery, localised chemotherapy or radiotherapy, ablation techniques and systemic treatment.
Surgery offers the best chance for cure and long term survival of HCC. It can be in the form of resection, which means removal of part of the liver together with the cancer, or a liver transplant. Unlike many other organs where complete removal of the organ (such as both breasts, the entire colon or stomach) is possible, a person cannot live without a liver. Resection is undertaken when complete removal of the cancer is feasible and yet leaving enough liver intact for the needs of the patient. The operation can be in the form of conventional open surgery where a wound of 15 to 20cm is necessary for the surgery to be performed, or in the form of laparoscopic surgery, where the entire surgery is carried out via keyhole access. Robotic liver surgery is also undertaken in SGH for suitable patients.
In cases where the cancer nodules are multiple, or where they are recurrent, or where the underlying liver disease is advanced, a liver transplant may be indicated. A donor liver can be from a person who is brain dead (cadaveric donor) or from a healthy individual who is willing to donate part of his/her liver (living donor). When indicated, a series of tests as well as assessments by various medical specialties is carried out to determine if the patient is suitable to undergo a liver transplant. Following a liver transplant, the patient will be required to take immunosuppression for life to prevent organ rejection.
Localised chemotherapy and radiotherapy
These treatments are undertaken when surgery is not possible. Localised chemotherapy is known as TACE (trans-arterial chemoembolisation). It involves delivery of chemotherapy directly to the cancer via a tube inserted at the groin, followed by blocking off of its blood supply. This has the advantage of delivery of a higher dose of chemotherapy to the cancer, whilst minimising the side effects to the rest of the body. Very often a single treatment session is sufficient, but repeated treatments might be required if the cancer is large, or multiple. Localised radiotherapy with yttrium 90 is similar to localised chemotherapy. It involves delivery of radioactive materials directly to the cancer via a tube inserted at the groin. Before this treatment is carried out, a series of tests is performed to determine if a patient is suitable for this form of treatment. The entire dose of radiotherapy is delivered in a single session.
Ablation techniques are suitable for small cancers usually less than 3cm in size. The efficacy of ablation in these small cancers is close to that achieved with surgery. The most common form of ablation technique is Radiofrequency Ablation (RFA). This involves insertion of a thin rod through the liver into the cancer, and using radiofrequency to generate heat which then causes cancer cell death. Another source of energy which is used for ablation is microwave. The access of the rod can be via the skin and guided by ultrasound or a CT scan. In this situation, general anaesthesia may not be necessary. Access of the rod can also be directly into the liver either via open or laparoscopic (keyhole) surgery, in which case general anaesthesia is required.
Systemic treatment is undertaken in advanced cases which are not suitable to the other options as mentioned before. Sorafinib, which is taken daily as an oral medication, is the most commonly prescribed systemic treatment. Occasionally intravenous chemotherapy may be given in selected cases.
In advanced cancer cases which are diagnosed not suitable for any of the above treatment options, there are trials which aim to determine if new treatment medication is effective in controlling the disease. Prognosis and surveillance Patients who are diagnosed and treated for HCC will be on lifelong follow up. This is because even when the cancer tumour is completely removed or ablated, the remaining liver is at risk for forming new cancers due to the underlying liver disease. Follow up treatments are through regular scans and blood test. When new cancers are noted on follow up, treatment can be started early such that it makes a difference to the outcome.
Colorectal liver metastasis
Spread of colorectal cancer to the liver is the most common type of secondary cancer to undergo liver resection. Whilst modern chemotherapy is highly effective in prolonging the life of patients with metastatic colorectal cancer, very few patients survive beyond three years with chemotherapy alone. Liver resection is feasible in 20% of these cases, and in combination with chemotherapy, offers the best chance for long term survival and cure. The management of patients with colorectal liver metastasis is a team effort, and requires inputs from surgeons, oncologists and radiologists. Depending on the clinical presentation, liver resection can be performed before institution of chemotherapy, in between rounds of chemotherapy, or at the completion of the chemotherapy regime. When diagnosed at the same time as the colorectal cancer, liver surgery may be performed at the same time as the colorectal surgery. With modern chemotherapy, liver surgery for colorectal liver metastasis is approaching 50% five-year survival and close to 30% ten-year survival.