| Highlights |
• In 2020, 905,700 people were diagnosed and 830,200 died from liver cancer worldwide. • Liver cancer is among the three leading causes of cancer death in 46 countries. • The number of new cases and deaths from liver cancer could increase by >55% by 2040. |
According to 2020 estimates, liver cancer is the sixth most commonly diagnosed cancer and the third most common cause of cancer death. Liver cancer is also the second most common cause of premature death from cancer. Liver cancer incidence and mortality rates have decreased in some East Asian countries, including Japan, China, and the Republic of Korea, but rates have increased in many countries around the world that previously had low incidence, such as the United States. , Australia and several European countries.
Risk factors for liver cancer include older age and sex (higher risk among men than women). Although HBV and HCV infections constitute the most important exogenous risk factors for primary liver cancer, excessive alcohol consumption and the related conditions of metabolic syndrome, type 2 diabetes, obesity, and nonalcoholic fatty liver disease They have also become important causes of primary liver cancer.
In this article, the authors describe where liver cancer ranks among all cancer types in terms of cancer diagnoses and deaths in countries around the world. Predictions of future liver cancer incidence through 2040 are also presented.
| Materials and methods |
Data on cases and deaths from primary liver cancer were extracted from the GLOBOCAN 2020 database, which includes 185 countries. Age-standardized incidence and mortality rates (ASR) per 100,000 person-years were calculated. Cases and deaths through 2040 were predicted based on incidence and mortality rates for 2020 and global demographic projections through 2040.
| Results |
In 2020, an estimated 905,700 people were diagnosed with liver cancer and 830,200 died from it worldwide. The global ASRs for liver cancer were 9.5 and 8.7 for new cases and deaths, respectively, per 100,000 people and were highest in East Asia (17.8 new cases, 16.1 deaths), Africa North (15.2 new cases, 14.5 deaths) and Southeast Asia (13.7 new cases, 13.2 deaths).
Liver cancer was among the top three causes of cancer death in 46 countries and was among the top five causes of cancer death in 90 countries. The ASRs for both incidence and mortality were higher among men than women in all regions of the world (male:female ASR ratio ranged from 1.2 to 3.6).
The number of new cases of liver cancer per year is projected to increase by 55% between 2020 and 2040, with 1.4 million people potentially diagnosed in 2040. It is predicted that 1.3 million people could die from liver cancer in 2040 (56.4% more than in 2020).
| Discussion |
Liver cancer was among the top three causes of cancer death in 46 countries and among the top five in 90 countries in 2020, despite not being the most commonly diagnosed cancer in most countries around the world.
Additionally, liver cancer was the second most common cause of premature cancer death in 2020, after lung cancer, with more than 530,000 deaths among people ages 30 to 69. Liver cancer survival remains poor even in high-income countries. With few improvements in survival in recent decades, primary prevention of liver cancer is key to reducing its burden worldwide.
Liver cancer due to some important risk factors with large attributable fractions is potentially preventable. For example, chronic HBV infection, responsible for more than half of liver cancer cases worldwide, is most common in countries in sub-Saharan Africa, some countries in Southeast Asia, and Central Asia. HBV infection can be prevented through neonatal immunization, which has already been introduced in 133 countries with global coverage of the three full vaccine doses estimated at 83% in 2020.
Another important risk factor for liver cancer is chronic HCV infection, which causes approximately 20% of liver cancer cases worldwide, and more than 50% of liver cancer cases are attributable to HCV in the most affected countries, including Egypt, the United States and Pakistan. There is no vaccine for HCV, but cure of chronic infection can be achieved with direct-acting antivirals (DAAs) and strategies can be applied to reduce transmission.
To explore the potential relationship between a country’s development and its liver cancer incidence or mortality rate, the human development index (HDI) was plotted by the liver cancer mortality rate and no correlation was found. However, the current burden of liver cancer could be influenced by other demographic factors. For example, a strong male predominance of liver cancer was found in all regions of the world. Ethnic disparities in liver cancer incidence have also been observed in studies using data from cancer registries in the US, with the highest rates found among American Indians/Alaska Natives, Hispanics, and Asians/Pacific Islanders.
The largest increases in liver cancer incidence could occur in high HDI countries, including China, due to population growth and aging. The largest relative increases could occur in low HDI countries, where the number of liver cancer cases and deaths per year could double by 2040. Given these changes, public health officials should prepare for the projected increase in demand of resources to manage care across the entire cancer trajectory, including improved access to palliative care.
| Conclusions |
Liver cancer is a leading cause of death in many countries and the number of people diagnosed is expected to increase. Efforts to reduce the incidence of preventable liver cancer should be prioritized.
