The liver is an organ that we can’t live without.Kathryn Hourdequin, MD
This year, more than 42,000 adults in the United States and 800,000 throughout the world will be diagnosed with cancer of the liver, the largest organ in the human body and part of the gastrointestinal tract. Incidence of this cancer has more than tripled since 1980 and continues to rise. “The liver is an organ that we can’t live without,” says Kathryn Hourdequin, MD, a medical oncologist at Norris Cotton Cancer Center who specializes in gastrointestinal cancer treatment. “The liver helps with digestion by breaking down and storing nutrients, transporting digestive bile, and converting nutrients to be used for energy. It also aids in clotting, and breaks down and filters alcohol, drugs and toxic wastes in the blood.” Here are 10 things you may not know about liver cancer.
- Most cancer found in the liver did not start there. “Most cancer in the liver is secondary,” says Hourdequin. “That means the cancer has spread there from somewhere else in the body, such as the pancreas, colon, stomach, breast or lung.” Of the cancers that do originate in the liver, hepatocellular carcinoma is the most common form in adults. It may begin as a single solid tumor or as many small cancerous lesions.
- The 5-year relative survival rate for all stages of liver cancer is 18 percent. According to the American Cancer Society, the rate is 31 percent for liver cancer that has not spread, and 2 percent for cancers that have spread to distant parts of the body. “It’s very difficult to give medications to people who have damaged livers because they are already facing low blood counts and compromised liver function and are at high risk of bleeding,” says Hourdequin. “Clinical trials and research are also difficult for the same reasons. I think this combination of challenges contributes to why we haven’t seen much progress in prognosis and survival rates.”
- Not all growths in the liver are cancer. Tumors may form in the liver’s blood vessels or cells. “If they’re small and not causing trouble and it’s clear on imaging that they’re not cancerous, we may opt to leave them there,” says Hordequin. “Liver disease is also not cancer and is handled by different specialists. If there is liver disease and cancer, we work hand-in-hand with gastroenterologists to manage both.”
- Risk factors for liver cancer include:
- Gender – Liver cancer is about three times more common in men than in women.
- Chronic viral hepatitis B and C – This virus often causes scarring of the liver called cirrhosis, which makes it difficult for the liver to function. These infections are why liver cancer is the most common cancer in many parts of the world.
- Heavy alcohol use – Excessive drinking often causes cirrhosis, increasing the risk for liver cancer. Alcohol abuse is a leading cause of cirrhosis in the US.
- Tobacco – Smoking increases the risk of liver cancer.
- Obesity – fatty liver disease, a common condition in obese people, can cause cirrhosis.
- Type 2 diabetes – there is an association between Type 2 diabetes and liver cancer, particularly among people who also drink heavily, smoke, have chronic hepatitis or are obese.
- Genetics and other diseases - Some inherited metabolic diseases can lead to cirrhosis. Certain rare diseases or environmental exposures such as to the vinyl chloride chemical in plastic may also increase risk for developing liver cancer.
- Steps that may lower risk of liver cancer include:
- Hepatitis B vaccine or screening for Hepatitis C in appropriate populations. “The rate of liver cancer in the US is increasing possibly because the hepatitis C population is ageing and starting to develop their cancers,” says Hourdequin. “There are guidelines in place for who should be screened. And there are more effective treatments for hepatitis B and C now.”
- Quitting tobacco
- Maintaining a healthy weight
- Limiting alcohol use. “Alcohol use and obesity rates are unfortunately going in the wrong direction right now. Reducing those rates could help in the future,” says Hourdequin.
- Liver cancer is difficult to detect early. There are few signs or symptoms of early liver cancer. Once tumors are large enough to cause physical symptoms or show up in a physical exam, the cancer is often already advanced.
- There are screening approaches in place for high-risk individuals. High risk means those who develop cirrhosis resulting from obesity or heavy alcohol use or have chronic hepatitis infections. Screening methods include:
- Imaging such as CT, MRI or ultrasound to locate tumors.
- Biopsy – removing a sample of suspicious tissue to look for cancer cells.
- Blood tests to look for high levels of a certain protein that may indicate liver cancer.
“For people with known cirrhosis from alcohol or any other cause, or chronic hepatitis with or without cirrhosis, they should undergo ultrasounds and blood tests every six months. Anybody who fits in those categories should be followed by a gastroenterologist and be under regular surveillance,” advises Hourdequin. “We want to pick up cancers early when they’re still treatable.”
- Symptoms of liver cancer are also symptoms of other conditions. These may include:
- Unexplained weight loss
- Digestive problems such as loss of appetite, feeling full quickly, nausea or vomiting
- An enlarged (swollen) liver or spleen, abdominal pain, swelling and fluid build-up
- Jaundice (yellowing of the skin and whites of the eyes)
If you notice an increase in one or more of these symptoms, your doctor may want to run some lab tests.
- Common liver cancer treatments include:
- Surgery to remove the tumor or have a liver transplant.
- Ablation to destroy small tumors when surgery is not an option. Ablation may involve radiofrequency (high-energy radio waves), microwave (electromagnetic waves), cryoablation (freezing), or concentrated alcohol injections. Newer ablation techniques for liver cancer are being studied.
- Radiation therapy using high-energy rays.
- Embolization to cut off the blood supply to larger tumors. “There are two blood supplies – the tumor is fed by one and the liver largely by the other. You can cut off the blood supply to the tumor and still leave the liver functional,” explains Hourdequin.
- Radioembolization – a combination of radiation therapy and embolization, this procedure involves injecting tiny radioactive beads directly into lesions to destroy them. “We use this technique when there are multiple spots and we need to treat a whole lobe,” says Hourdequin.
- Targeted therapy to block proteins that help tumors grow.
- Immunotherapy that kick-starts the body’s own immune system to fight the cancer. Immunotherapy has recently been FDA approved as a second-line therapy.
- Chemotherapy when other treatments are not working.
“Once the disease has spread, success of any kind of treatment is still very limited,” notes Hourdequin. “Although immunotherapy is starting to change that for a small portion of people.”
- Research on new treatments and prevention methods is in progress. Studies include:
- Vaccination and improved treatments for viral hepatitis and other virus therapies.
- Blood tests and imaging modalities.
- Advanced surgical techniques for partial liver removals and liver transplants.
- Combination drug therapies, ablation and targeted therapies.
- Determination of risk and risk of cancer coming back.
“Clinical trials and research are challenging as many patients are already in advanced stage and have health problems that prevent them from being eligible for studies. It’s harder to do research in this patient population on average,” notes Hourdequin.
Each person’s medical history, environment, habits and behaviors are different. Your providers can discuss your individual liver cancer risk factors and make recommendations that are appropriate for you.