Liver cancer on the rise: Canadians need to know the risk factors for this largely preventable cancer

Gillian Bromfield, Director, Cancer Control Policy, Canadian Cancer Society. (CNW Group/Canadian Cancer Society (National Office))

Dr. Prithwish De, Epidemiologist, Canadian Cancer Society. (CNW Group/Canadian Cancer Society (National Office))

TORONTO, May 29, 2013 /CNW/ - Liver cancer is one of the fastest rising of all cancers in Canada, yet most Canadians do not know enough about risk factors and prevention, according to Canadian Cancer Statistics 2013, released today by the Canadian Cancer Society in collaboration with the Public Health Agency of Canada and Statistics Canada.

Since 1970, the incidence rate of liver cancer has tripled in Canadian men and doubled in Canadian women, rising every year by 3.6% in men and 1.7% in women.

Liver cancer has a very poor prognosis, with a 5-year relative survival rate of only 20%. While it is still a relatively rare cause of death in Canada (1,000 deaths expected this year), the death rate in Canadian men has doubled since 1970. And worldwide it is the 3rd leading cause of cancer death after lung and stomach cancer, accounting for about 700,000 deaths per year.

The main risk factors for liver cancer are chronic hepatitis B and C infections. However, hepatitis is not well recognized as a serious health threat. In addition, many people don't know that they have hepatitis. Approximately 600,000 Canadians are infected with hepatitis B or C, according to the Public Health Agency of Canada.

Heavy alcohol use, obesity, diabetes, smoking and several other factors are also associated with a higher risk of liver cancer.

If more isn't done to address the risk factors for liver cancer, incidence and death rates are expected to continue to rise in Canada.

Recommendations from the report

To lower the rising rates of liver cancer cases and deaths, it will be important to:

  • Find and treat people who have hepatitis B or C. This can reduce progression to chronic infection, which can lead to cancer.

  • Encourage primary healthcare providers to offer the hepatitis B vaccination or appropriate testing and treatment for hepatitis B or C to at-risk people, including newcomers to Canada if they come from parts of the world where hepatitis B, hepatitis C or liver cancer are common
    .
  • Raise awareness among Canadians about the risk factors for liver cancer, especially its links with hepatitis B and C, how to reduce the risk of liver cancer and how to get tested and treated for hepatitis infection if they belong to an at-risk group.

  • Encourage primary healthcare providers to counsel patients about alcohol use, maintaining a healthy weight and not smoking, which can reduce the risk of liver cancer, in addition to having other health benefits.

  • Conduct more research in Canada about the most effective ways to educate the public about the disease and to better understand the needs of liver cancer patients and survivors.

  • Have more Canadian data to understand the best strategies for hepatitis B and C screening, and how best to engage communities in promoting screening for hard-to-reach populations.

"It's important to draw attention to the rising incidence and death rates for liver cancer so that we can tackle this important public health problem," says Dr Prithwish De, epidemiologist with the Canadian Cancer Society and the lead author of the special topic on liver cancer. "The good news is that liver cancer is largely preventable by modifying risk factors."

More about liver cancer in Canada

  • In 2013, it is estimated that there will be over 2,000 new cases of liver cancer and about 1,000 deaths from the disease.

  • The incidence rate is higher in Canadian men at 6.9 cases per 100,000 than in Canadian women at 1.9 cases per 100,000.

  • Liver cancer is challenging to identify and treat because there are usually no symptoms until its later stages when the prognosis is poor. As a result, the death rate is high and the 5-year relative survival rate is low.

  • Treatment can involve surgery, radiofrequency ablation, chemotherapy and/or radiation.

  • Worldwide, liver cancer is the 6th most commonly diagnosed cancer. In Canada, liver cancer is a rare but rising cancer.

More about hepatitis B
Hepatitis B infection accounts for about one-quarter (23%) of liver cancer cases in developed countries, but the percentage is much higher in parts of the developing world where hepatitis B is common, such as eastern Asia and sub-Saharan Africa.

  • Hepatitis B can be prevented with a vaccine. All provinces in Canada offer universal vaccination against this form of hepatitis, although the vaccination strategies vary from province to province. Some provinces offer universal vaccination to newborns, while other provinces offer universal vaccination to adolescents.
  • The hepatitis B virus is commonly passed through exposure to contaminated blood or body fluids between sexual partners, by sharing needles among drug users or by sharing personal care articles, such as razors, scissors, nail clippers or toothbrushes, with an infected person.

More about hepatitis C

  • Hepatitis C infection accounts for approximately 30%-50% of liver cancer cases in North America. The percentage is lower in the developing world.

  • There is currently no vaccine to prevent hepatitis C.

  • In Canada, the hepatitis C virus is spread through exposure to contaminated blood and is sometimes transmitted through sexual activity.

  • Those at highest risk for infection include:
    • injection drug users
    • immigrants from regions where hepatitis C is common, such as southern Europe, and parts of Africa and Asia, where transmission can occur through medical procedures using unsterilized equipment
    • people exposed occupationally to contaminated blood, such as nurses
    • Aboriginal people
    • recipients of blood transfusions before the implementation of blood screening for hepatitis C in Canada

General highlights - Canadian Cancer Statistics 2013

  • Over the past 30 years, the death rate for all cancers combined has been declining for males in most age groups and for females in all age groups, except over 70.

  • There were no increases in death rates for most types of cancer in men and women, with the exception of liver cancer in both sexes and lung cancer in women.

  • The age-adjusted 5-year relative survival rate for all cancers combined in 2006-2008 was 63%, an improvement over the survival rate of 56% in 1992-1994.

  • An estimated 187,600 new cases of cancer (excluding 81,700 cases of non-melanoma skin cancer) and 75,500 deaths from cancer are expected to occur in Canada in 2013.

  • Rates of the disease are generally stabilizing for new cases and declining for deaths. However, the number of new cancer cases and cancer deaths continues to rise as the Canadian population grows and ages. Four types of cancer - lung, breast, colorectal and prostate - account for 52% of newly diagnosed cancers.

"Cancer, in all its forms, touches each and every one of us," says Minister of Health Leona Aglukkaq. "Fighting cancer is a priority for our government and that is why every year we invest in research and the Canadian Partnership Against Cancer. The Public Health Agency of Canada is pleased to work with the Canadian Cancer Society to increase public awareness about cancer prevention and control."

Canadian Cancer Statistics 2013 was prepared through a collaboration of the Canadian Cancer Society, the Public Health Agency of Canada, Statistics Canada and provincial and territorial cancer registries. For more information about Canadian Cancer Statistics 2013, visit cancer.ca.

About the Canadian Cancer Society

For 75 years, the Canadian Cancer Society has been with Canadians in the fight for life. We have been relentless in our commitment to prevent cancer, fund research and support Canadians touched by cancer. From this foundation, we will work with Canadians to change cancer forever so fewer Canadians are diagnosed with the disease and more survive. Visit cancer.ca or call us at 1-888-939-3333 (TTY 1-866-786-3934).

Media backgrounder #1: Highlights of 2013 liver cancer statistics

Liver cancer is the special topic in Canadian Cancer Statistics 2013, released today by the Canadian Cancer Society in collaboration with the Public Health Agency of Canada and Statistics Canada.

Overall liver cancer facts

  • Liver cancer is one of the fastest rising cancers in Canada.

  • While it is still considered a rare cancer, accounting for an estimated 1% of all new cancer diagnoses and deaths in 2013, the incidence rate of liver cancer has tripled in Canadian men and doubled in women since 1970.

    • Between 1970 and 2007, there was an average annual increase of 3.6% per year in liver cancer incidence for men. For women, there was an annual average increase of 1.7%.
  • The liver cancer death rate is also increasing:
    • The largest annual increase was between 1991 and 2009, when the liver cancer death rate in men rose by 2.5% per year. In women, the average annual death rate has risen 1.8% per year between 1994 and 2009.
  • An estimated 2,100 Canadians will be diagnosed with liver cancer in 2013 (1,550 men and 490 women). An estimated 1,000 will die from the disease (780 men and 240 women).

  • Liver cancer has a very poor prognosis, with a five-year relative survival rate of only 20%.

  • Liver cancer is the 3rd leading cause of cancer death worldwide after lung and stomach cancer, accounting for about 700,000 deaths per year worldwide.

  • Hepatocellular carcinoma is the main type of liver cancer that accounts for the majority (71.9%) of liver cancers in Canada. Cholangiocarcinoma is a more rare type of liver cancer affecting the bile duct, accounting for 4.1% of liver cancers in Canada.

Survival

  • Based on estimates for 2006-08, the five-year relative survival rate for liver cancer in Canada is 20 per cent (4 out of 5 people diagnosed will die within 5 years compared to people of the same age in the general population who don't have cancer).

Prevalence

  • As of January 2009, it is estimated there were 2,985 Canadians (2,242 males and 743 females) who had been diagnosed with primary liver cancer in the previous 10 years and were still alive on that date.

Diagnosis and treatment

  • In most cases, liver cancer does not cause any symptoms until very late in the course of the disease
  • People with liver cancer often present with large, late-stage tumours that are generally not curable.
  • People with liver cancer may present with symptoms such as jaundice, abdominal swelling, weight loss, night sweats, fatigue or abdominal pain
  • Depending on the stage of the cancer and the health of the liver, treatment may include surgery to remove the tumour, radiofrequency ablation, chemoembolization, chemotherapy, or liver transplantation.

Liver cancer risk factors

Chronic hepatitis B and C infection are the main risk factors for liver cancer. Smoking, heavy alcohol use, obesity and diabetes are also associated with a higher risk of liver cancer.

Hepatitis B and C

  • Hepatitis B and C are both viral infections that cause inflammation of the liver. Chronic infection with hepatitis B or C damages the liver, which can eventually lead to liver cancer.

  • About 5-10% of people infected with hepatitis B become chronic carriers of the virus.

  • About 75-85% of people infected with hepatitis C become chronic carriers of the virus. Many people infected with hepatitis B or C are not aware of their infection.

  • It is possible that liver cancer rates are rising in Canada because of increasing immigration of persons chronically infected with hepatitis B or C to Canada from areas of the world where these infections are common.

  • Another reason is that spread of infection occurs unknowingly from infected people to uninfected people (such as between household members for hepatitis B or among drug users for hepatitis C).

  • The hepatitis B virus is commonly passed through exposure to contaminated blood or body fluids between sexual partners, sharing injecting equipment among drug users, or among household members by sharing personal care articles such as razors, scissors, nail clippers or toothbrushes with an infected person. The virus can also be transmitted from mother to child during birth.

  • Most hepatitis C infection is spread through contact with contaminated blood.

  • Last year, the US introduced hepatitis C screening guidelines for Americans born between 1945 and1965 after considering the high prevalence of hepatitis C in this age cohort. Work is underway at the Public Health Agency of Canada (PHAC) to determine which age and population groups could benefit from hepatitis C screening as suggested in the US. The Society is supportive of PHAC's work in this area.

Smoking, heavy alcohol use, obesity and diabetes

  • In the US and northern Europe, more than half of liver cancer cases are not linked to hepatitis B or hepatitis C, implying that other risk factors may play a role. These include alcohol-related cirrhosis of the liver, smoking, fatty liver disease caused by obesity, and diabetes.

Other possible liver cancer risk factors

  • occupational exposure to vinyl chloride or PCBs
  • metabolic diseases (such as hereditary hemachromatosis, alpha-antitrypsin deficiency)
  • primary biliary cirrhosis
  • exposure to aflatoxin (a carcinogenic toxin produced by an agricultural fungus, typically in the developing world)

Reducing the risk of liver cancer

There are a number of things Canadians can do to reduce their risk of liver cancer. These include:

  • Protect yourself against hepatitis infection: chronic infection with hepatitis B or C virus increases the risk of developing liver cancer.
    • People can get vaccinated for hepatitis B if they haven't already done so. There is no vaccine for hepatitis C, but research to develop a vaccine is underway.
  • Practise safe sex.

  • Don't share needles or other drug-use equipment.

  • Get treated if you have a hepatitis infection:
    • Treatment of chronic hepatitis B infection can reduce the amount of virus in a person, which may lead to a lower risk of liver cancer.

    • Treatment of chronic hepatitis C infection can reduce and in some people eliminate the virus completely.

  • Limit the amount of alcohol you drink.

  • Be a non-smoker.

  • Be physically active and maintain a healthy body weight.

Research

  • More research is needed in Canada about the most effective way for educating the public about the disease and to better understand the needs of liver cancer patients and survivors.

  • More Canadian data is also needed to understand the best strategies for hepatitis B and C screening and treatment and how best to engage communities in promoting screening for hard-to-reach populations.

Glossary

Five-year relative survival is the proportion of people alive five years after their diagnosis, adjusted for the deaths expected for people of the same age in the general population. Relative survival is the most often used method for analyzing the survival of cancer patients across a population.

Prevalence is the number of people with a new or previous cancer diagnosis in a given population who are alive on a specific date (known as the index date).

Media backgrounder #2: Canadian Cancer Statistics 2013

Cancer in Canada: Fast facts

Canadian Cancer Statistics 2013 was released today by the Canadian Cancer Society in collaboration with the Public Health Agency of Canada and Statistics Canada.

Current estimates of new cases and deaths

In 2013:

  • An estimated 187,600 new cases of cancer will be diagnosed in Canada (not including approximately 81,700 cases of non-melanoma skin cancer).

  • There will be an estimated 75,500 deaths from cancer.

Every hour of every day, an average of 21 people will be diagnosed with some type of cancer, and nine people will die from the disease.

  • Of the newly diagnosed cases, more than one half (52%) will be prostate, breast, lung, and colorectal cancers.

  • Canadians aged 50-79 years will represent almost 70% of all new cancer cases and 62% of cancer deaths in 2013. The highest proportion of new cancer cases (51,600 cases or 28%) will occur in Canadians aged 60-69, while the highest proportion of deaths from cancer (25,500 deaths or 34%) is expected in those aged 80 and older.

The number of new cancer cases continues to rise steadily as the Canadian population grows and ages.

Prostate cancer

  • Prostate cancer is the most commonly diagnosed cancer among Canadian men (25% of all new cases in men).

  • In 2013, it is estimated that approximately 23,600 Canadian men will be diagnosed with prostate cancer, and about 3,900 will die from the disease.

  • The incidence and death rates have both been declining, and the death rate has been declining significantly by almost 4% per year between 2001 and 2009, which likely reflects increased testing for the cancer and improved treatment.

Breast cancer

  • Breast cancer continues to be the most commonly diagnosed cancer among Canadian women (26% of all new cases in women).

  • In 2013, it is estimated that approximately 23,800 Canadian women will be diagnosed with breast cancer, and about 5,000 will die from it.

  • Although the incidence and death rates have both been declining, the death rate has been decreasing significantly, with a reduction of 42% since peaking in 1986. The decrease in death rate has been 2.4% per year between 2000 and 2009. This is likely because of earlier diagnosis through screening mammography and availability of improved treatment. The breast cancer death rate is the lowest it has been since 1950.

Lung cancer

  • Lung cancer remains the leading cause of cancer death for both men and women.

  • Lung cancer takes the lives of more Canadians than breast, prostate and colorectal cancers combined.

  • Tobacco use causes about 85% of lung cancer cases. Other causes of lung cancer include radon, asbestos exposure, air pollution, certain lung diseases, a family history of lung cancer and exposure to certain occupational chemicals.

  • In women:
    • The lung cancer incidence rate has been increasing since at least the 1960s.

    • The incidence rate increased by 1.1% per year between 1998 and 2007 but is projected to be stabilizing.

    • The death rate for women between 2000 and 2009 shows a slight increase of 0.6% per year.
  • Among men, lung cancer incidence and death rates began to level off in the mid-1980s after several decades of increase and have been declining ever since. Incidence rates have dropped by 1.8% per year between 1998 and 2007 and death rates by 2.2% per year between 2000 and 2009.

The difference between the male and female trends reflects the drop in smoking that began for men in the early 1960s and much later for women, in the 1980s.

Colorectal cancer

  • For both men and women, the incidence rate has decreased by 0.8% per year since 2000.

  • Death rates continue to decline for both men and women - by 2.7% per year in men between 2004 and 2009 and 1.8% per year in women between 2000 and 2009. This is likely the result of improvements in treatment, such as chemotherapy, and increasing availability and uptake of screening.

Canadian Cancer Statistics 2013 was prepared through a collaboration of the Canadian Cancer Society, the Public Health Agency of Canada, Statistics Canada and provincial and territorial cancer registries.

For more information about Canadian Cancer Statistics 2013, visit cancer.ca.

For 75 years the Canadian Cancer Society has been with Canadians in the fight for life. We have been relentless in our commitment to prevent cancer, fund research and support Canadians touched by cancer. From this foundation, we will work with Canadians to change cancer forever so fewer Canadians are diagnosed with the disease and more survive. When you want to know more about cancer, visit our website at cancer.ca or call our toll-free bilingual Cancer Information Service at 1 888 939-3333; TTY, 1 866 786-3934.

Image with caption: "Gillian Bromfield, Director, Cancer Control Policy, Canadian Cancer Society. (CNW Group/Canadian Cancer Society (National Office))". Image available at: http://photos.newswire.ca/images/download/20130529_C2505_PHOTO_EN_27101.jpg

Image with caption: "Dr. Prithwish De, Epidemiologist, Canadian Cancer Society. (CNW Group/Canadian Cancer Society (National Office))". Image available at: http://photos.newswire.ca/images/download/20130529_C2505_PHOTO_EN_27103.jpg

SOURCE: Canadian Cancer Society (National Office)


For further information:

Sasha Anopina
Bilingual Communications Specialist
Canadian Cancer Society
sasha.anopina@cancer.ca
416 934-5338