Cancer-Specific Mortality Rates Vary Widely Around the World

A worldwide study of cancer mortality has revealed worrying trends. According to new research by Sedeta and colleagues in Cancer Epidemiology, Biomarkers & Prevention, mortality from most major cancers fell in most countries studied, but deaths from lung cancer among women and liver cancer among men rose alarmingly. Increasing lung cancer mortality among women may reflect more widespread smoking, while increasing liver cancer mortality among men may be attributable to alcohol use and the obesity epidemic.

The findings show substantial differences between countries, with mortality rates for lung and cervical cancer varying by as much as 10-fold. This is a serious warning for public health authorities and individuals: fighting cancer requires a global effort covering all cancer types and regions, rather than only particular diseases or geographical areas.

Health systems must be strengthened in high-income countries as well as resource-limited settings, so that established prevention and control measures can be implemented widely and equitably. Each country and region faces different cancer risks.

Study Details

The researchers analysed mortality from the eight most common cancers in 47 countries across different world regions: breast, lung, colorectal, prostate, stomach, liver, cervical and oesophageal cancer. Using high-quality World Health Organization mortality data and age-standardised rates, they identified distinct trends and patterns for each cancer type.

Results

• Lung cancer mortality among women rose by 0.3% to 4.3% annually in 24 countries. The fastest increases were in Spain (4.3%), Uruguay (3.7%) and Greece (3.2%). Of the 24 countries with rising female lung cancer mortality, 22 were in Europe.
• Liver cancer mortality among women increased by 0.9% to 4.5% annually in 15 countries. The largest rises were in England (4.5%), Norway (3.4%), Denmark (3.1%) and Australia (3.1%).
• Among men, liver cancer mortality rose faster than among women in 23 of the 47 countries, with annual increases of 0.8% to 5.8% across Europe, North America and Australia. The fastest rises were in Ireland (5.8%), Norway (5.3%) and Malta (4.8%).
• The researchers suggested that rising liver cancer mortality may largely reflect a high prevalence of hepatitis C, alongside non-viral causes, particularly in the United States, including obesity, diabetes, metabolic syndrome, non-alcoholic fatty liver disease and heavy alcohol consumption.
• Cervical cancer mortality fell by 0.4% to 5.2% annually in 28 of the 47 countries, most rapidly in Singapore (5.2%), Switzerland (4.7%) and the Republic of Korea (4.4%). However, it rose by 0.5% to 2.5% annually in six countries in different world regions: Kyrgyzstan, Japan, Greece, Italy, Argentina and Latvia.

Commentary

The researchers concluded that effective measures such as tobacco control and vaccination, promotion of healthy lifestyles and organised screening could help prevent a large share of cancer cases worldwide.

This comprehensive study of global cancer-specific mortality suggests that cancer control requires a universal, inclusive approach rather than a focus on selected cancers or regions. Developed and developing countries alike should implement all established strategies to prevent and treat cancer, applying them wherever needed to reduce the cancer burden and mortality.