On December 15, the International Agency for Research on Cancer (IARC) released the latest estimates on the global burden of cancer. The GLOBOCAN 2020 database, accessible online as part of the IARC Global Cancer Observatory, provides estimates of incidence and mortality in 185 countries for 36 types of cancer and for all cancer sites combined for the year 2020. The global cancer burden is estimated to have risen to 19.3 million new cases and 10.0 million deaths in 2020.
One in 5 people worldwide develop cancer during their lifetime, and 1 in 8 men and 1 in 11 women die from the disease. Worldwide, the total number of people who are alive within 5 years of a cancer diagnosis—called the 5-year prevalence—is estimated to be 50.6 million.
Major Cancer Types in 2020
The 10 most common cancer types account for more than 60% of the newly diagnosed cancer cases and more than 70% of the cancer deaths. Female breast cancer is the most commonly occurring cancer worldwide (11.7% of the total new cases), followed by lung cancer (11.4%), colorectal cancer (10.0%), prostate cancer (7.3%), and stomach cancer (5.6%).
Lung cancer is the leading cause of cancer death (18.0% of the total cancer deaths), followed by colorectal cancer (9.4%), liver cancer (8.3%), stomach cancer (7.7%), and female breast cancer (6.9%).
In men, lung cancer is the most commonly diagnosed cancer and the leading cause of cancer death, followed by prostate cancer and colorectal cancer for incidence and liver cancer and colorectal cancer for mortality. In women, breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death, followed by colorectal cancer and lung cancer for incidence and lung cancer and colorectal cancer for mortality.
Projected Burden of Cancer in 2040
Worldwide, an estimated 28.4 million new cancer cases are projected to occur in 2040, a 47% increase from the estimated 19.3 million cases in 2020. Using the four-tier Human Development Index (HDI) as a marker of the degree of national social and economic transition, countries classified as having low or medium HDI will have the greatest relative increases in cancer incidence by 2040 (a 95% and 64% rise from 2020, respectively). In addition, many of these countries are experiencing a marked increase in prevalence of known cancer risk factors that currently prevail in countries with high and very high HDI, including smoking, unhealthy diet, excess body weight, and physical inactivity.
Freddie Bray, MSc, PhD
“The ongoing changes in population structure, the environments in which people live, and the extent to which health systems are capable of delivering effective cancer control interventions will together drive the scale and profile of cancer incidence, mortality, and prevalence that will emerge over the next decades,” said Freddie Bray, MSc, PhD, Head of the Section of Cancer Surveillance at IARC.
Breast Cancer Incidence
Female breast cancer has now surpassed lung cancer as the most commonly diagnosed cancer worldwide. The estimated 2.3 million new cases indicate that 1 in every 8 cancers diagnosed in 2020 is breast cancer. The disease is the fifth-leading cause of cancer mortality worldwide, with 685,000 deaths in 2020. In women, breast cancer accounts for 1 in 4 cancer cases and 1 in 6 cancer deaths, and the disease ranks first in terms of incidence and mortality in most countries around the world (in 159 and 110 countries, respectively).
Marked changes in lifestyle, sociocultural contexts, and built environments are having a major impact on the prevalence of risk factors for breast cancer in many countries with low and medium HDI. These risk factors include the postponement of childbearing and having fewer children, as well as greater levels of excess body weight and physical inactivity. Breast cancer incidence rates are converging worldwide, yet breast cancer mortality rates and survival proportions are lower in settings with lower HDI, largely because of late-stage presentation.
Elisabete Weiderpass, MD, MSC, PhD
“There is an overwhelming need for evidence-based and resource-stratified guidelines that support the phased implementation of breast cancer early detection and treatment into real-world practice,” said IARC Director Elisabete Weiderpass, MD, MSC, PhD. “The World Health Organization and IARC are currently working together to launch a new global breast cancer initiative in 2021, focusing on improving timely diagnosis and comprehensive treatment to improve population-level outcomes.”
New Features of the Global Cancer Observatory
The Global Cancer Observatory website includes, via the Cancer Today subsite, facilities for the tabulation and graphical visualization of the GLOBOCAN 2020 database for 185 countries and 36 cancer types (as well as all cancer sites combined), by age and sex. The revamped Cancer Tomorrow subsite provides a suite of data visualization tools to predict the future incidence and mortality burden for a given country or region up until 2040. The baseline predictions assume that the 2020 rates will not change, and these are applied to national population projections that account for future population growth and ageing. A new feature of Cancer Tomorrow is the ability for the user to specify the change in incidence or mortality trends from 2020, thus incorporating how the cancer rates may evolve in the future.
“The updated global cancer figures for 2020 highlight the diverse cancer patterns seen today as well as the expected rise in the cancer burden over the next decades. There is an urgent need to address the disease as both a public health issue and an economic problem through effective cancer action,” said Dr. Weiderpass. “Cancer prevention has a key role to play. Effective interventions for prevention and early detection are available and must be integrated into cancer planning to control the predicted upsurge of this devastating disease.”
