Mortality Rates for All Major Cancers Decreasing Globally

Scientists at the American Cancer Society (ACS) and Brookdale University Hospital Medical Center report recent mortality rates for all major cancers decreased in most of the studied countries except lung cancer in females and liver cancer in males, where increasing rates were observed in most countries. The research also showed that cancer-specific mortality rates varied substantially across countries, with rates of lung and cervical cancer varying by 10-fold. The study was published in the journal Cancer Epidemiology, Biomarkers & Prevention, a publication of the American Association for Cancer Research (AACR).

“These findings reinforce the importance of strengthening the health systems not only in resource-limited countries but also in high-income countries across the world for broad and equitable implementation of known cancer prevention and control interventions,” said Dr Ahmedin Jemal, senior vice president, surveillance and health equity science at the American Cancer Society and senior author of the study. “Doing this will further mitigate the rising cancer burden and reduce cancer disparities worldwide.”

The study focused on analyzing mortality rates for the eight leading types of cancer-related deaths, namely, cancers of the female breast, lung, colon and rectum, prostate, stomach, liver, cervix, and esophagus, in 47 countries spanning diverse regions of the world. By examining high-quality World Health Organization mortality data and utilizing age-standardized rates, the researchers were able to unravel the distinct trends and patterns associated with each type of cancer.

Highlights from the study results include:

• Lung cancer mortality rates increased in females in 24 countries by 0.3%-4.3% annually with the most rapid increase seen in Spain (4.3% per year), Uruguay (3.7% per year), and Greece (3.2% per year). Of the 24 countries for which mortality rates increased among females, 22 were in Europe. Liver cancer mortality rates also increased in females in 15 countries by 0.9%-4.5% annually with the most rapid increases in the UK (4.5% per year), Norway (3.4% per year), Denmark (3.1%), and Australia (3.1% per year).
• Liver cancer mortality rates in males increased in 23 of 47 countries, including many in Europe, North America, and Oceania, by 0.8%-5.8% annually with the most rapid increases in Ireland (5.8% per year), Norway (5.3% per year), and Malta (4.8% per year).
• The increase in death rates from liver cancer is thought to largely reflect the high prevalence of Hepatitis C infection (USA) and nonviral etiology, such as obesity, diabetes, metabolic syndrome, and non-alcoholic fatty liver disease as well as heavy alcohol consumption.
• Cervical cancer mortality rates decreased in 28 of 47 countries by 0.4%-5.2% per year with the most rapid decreases in Singapore (5.2% per year), Switzerland (4.7% per year), and the Republic of Korea (4.4% per year). Rates, nonetheless, increased by 0.5%-2.5% annually in six countries across different regions of the world (Kyrgyzstan, Japan, Greece, Italy, Argentina, and Latvia).

Dr Ephrem Sedeta, Brookdale University Hospital Medical Center and lead author of the study, noted that understanding the current cancer burden and its trends is a crucial step to monitoring progress made against cancer and identifying disparities across countries. “There is limited published data on recent cancer mortality trends worldwide. The findings based on the up-to-date cancer mortality data may help set priorities for national and international cancer control efforts and in so doing, reduce the marked global cancer disparities observed today,” Sedeta said.

The researchers emphasize the importance of implementing effective measures such as tobacco control, vaccination, promoting healthy lifestyles, and systematic screening to prevent a large proportion of cancer cases globally.

ACS researcher Dr Hyuna Sung contributed to the study. Dr Freddie Bray and Mathieu Laversanne from the International Agency for Research on Cancer were also contributors to this research.