Highlights
- Rates of liver cancer (hepatocellular carcinoma) have been increasing for the past 30 years in Ontario.
- Major risk factors for liver cancer include alcohol consumption, tobacco smoking, and chronic hepatitis B and C infections.
- The incidence of liver cancer can be reduced with prevention and treatment opportunities.
The incidence (new cases) of hepatocellular carcinoma, the most common type of liver cancer, has been increasing significantly over the past 30 years in Ontario, at 3.9% per year from 1984 to 2013 for both sexes combined. During this period, the incidence rate of liver cancer jumped from 2.2 per 100,000 in 1984 to 6.5 per 100,000 in 2013.
Most notable has been the jump in liver cancer incidence rates in males, which increased from 3.8 per 100,000 in 1984 to 10.5 per 100,000 in 2013. The liver cancer incidence rate in females showed less of an increase, rising from 1.0 per 100,000 in 1984 to 3.0 per 100,000 in 2013. These rate increases in both sexes correspond to an increase in the number of liver cancer cases diagnosed in Ontario from 148 in 1984 to 907 in 2013.
Because the risk of developing liver cancer increases with chronic hepatitis B and/or C infection,[1] Ontario’s liver cancer pattern may be related to immigration from developing countries, where HBV and HCV are common. Liver cancer was found to be particularly high in the greater Toronto area, which has a higher percentage of immigrants than the rest of the province.[2] It is estimated that in Ontario, over a third of all liver cancer cases (about 330 cases diagnosed in 2013) were due to HBV or HCV infection.[3]
Other known modifiable risk factors for liver cancer include alcohol consumption, tobacco smoking and adult body fatness.[1][4][5] There is evidence that having more than 3 alcoholic drinks a day is associated with an increased risk of liver cancer,[4] and the more someone smokes or is overweight (as measured by body mass index), the higher their risk of developing liver cancer.[4][5]
There are a number of programs and policies in Ontario aimed at preventing liver cancer. These programs and policies include raising tobacco taxes, reducing alcohol outlet density, developing programs to reduce household food insecurity, and supporting food literacy and physical activity programs in secondary schools.[6] At the provincial level, Ontario has implemented a school-based HBV immunization program for Grade 7 students and offers treatment to people who are chronically infected with HCV.[3] These organized efforts, along with people choosing to make better lifestyle choices (i.e., reduced alcohol consumption, tobacco smoking and physically inactivity), can help reduce the incidence of liver cancer in the province. More information on these risk factors can be found in the Cancer Risk Factors in Ontario report series.