Cancer is a leading cause of death worldwide. In 2020 alone, there were about 19.3 million new cancer cases and almost 10 million cancer deaths globally. With so many different types of cancers, it can be helpful to know which are the most commonly diagnosed. This allows public health officials to focus cancer screening and prevention efforts on the cancers that impact the most people.
In this article, we will go over a ranking of the most common cancers worldwide based on 2020 estimates from the World Health Organization (WHO) and the International Agency for Research on Cancer (IARC). We will count down from the 12th most common cancer to the most commonly diagnosed cancer worldwide. Along with the ranks, we will also provide key statistics on incidence rates, mortality rates, and trends over time for each of the most prevalent cancer types.
12. Stomach Cancer
Starting off the list is stomach cancer, or cancer that starts in the stomach. In 2020, there were about 1.1 million new cases of stomach cancer diagnosed globally, accounting for 5.6% of all cancer cases. Stomach cancer is more common in men than women, with a male-to-female ratio of approximately 2-to-1 for new stomach cancer cases worldwide. The highest stomach cancer rates are found in Eastern Asia, Eastern Europe, and South America.
While stomach cancer remains a leading cause of cancer deaths, incidences have been declining worldwide over the past several decades. Experts cite improvements in food refrigeration and decreased reliance on salt-preserved foods as potential factors in the downward trend. Still, stomach cancer resulted in about 769,000 deaths worldwide in 2020.
11. Liver Cancer
Liver cancer is the 11th most commonly diagnosed cancer globally. In 2020, there were approximately 906,000 new cases of liver cancer, representing about 4.6% of all cancer cases. Liver cancer is over 3 times more common in men than women. The highest rates are found in Eastern and South-Eastern Asia as well as Northern and Western Africa.
The most common form of liver cancer is hepatocellular carcinoma, which starts in the main type of liver cell (hepatocyte). Chronic infections with hepatitis B and C are major risk factors for liver cancer worldwide, due to the inflammation they cause that can lead to liver cirrhosis and eventually cancer. Liver cancer led to about 830,000 deaths in 2020, making it a leading cause of cancer mortality.
10. Esophageal Cancer
Esophageal cancer, or cancer that starts in the esophagus, comes in as the 10th most commonly diagnosed cancer worldwide. There were approximately 600,000 new esophageal cancer cases in 2020, representing 3% of all cancer cases. Esophageal cancer is more than 3 times more common in men than women.
There are two main subtypes of esophageal cancer: esophageal squamous cell carcinoma and esophageal adenocarcinoma. The highest rates of esophageal squamous cell carcinoma are found in Eastern Asia and Eastern/Southern Africa. Esophageal adenocarcinoma is more common in Northern America and Western Europe.
Esophageal cancer led to approximately 544,000 deaths worldwide in 2020. Risk factors like tobacco use, alcohol consumption, obesity, and acid reflux contribute to esophageal cancer development.
9. Non-Hodgkin Lymphoma
Non-Hodgkin lymphoma refers to a group of blood cancers that start in the lymphatic system. In 2020, there were an estimated 572,000 new cases of non-Hodgkin lymphoma worldwide, accounting for 2.9% of all cancer cases. The male-to-female ratio is around 1.6-to-1.
There are over 60 subtypes of non-Hodgkin lymphoma. While some are indolent (slow-growing), others are more aggressive. Non-Hodgkin lymphoma resulted in approximately 312,000 deaths worldwide in 2020.
8. Prostate Cancer
Prostate cancer begins when cells in the prostate gland start to grow out of control. With around 1.4 million new cases in 2020 (7.3% of all cancers), prostate cancer ranks as the 8th most commonly diagnosed cancer worldwide. It is the most common cancer diagnosed in men.
Prostate cancer rates vary widely worldwide, with the highest incidences found in Australia/New Zealand, Northern America, Northern and Western Europe. Increased screening using prostate-specific antigen (PSA) testing has led to more prostate cancer diagnoses at early stages in recent decades.
While prostate cancer can be serious, most men diagnosed with localized tumors do not die from the disease. The approximate 467,000 prostate cancer deaths worldwide in 2020 mostly occurred in cases diagnosed at more advanced stages.
7. Colorectal Cancer
Colorectal cancer starts in the colon or rectum. With around 1.9 million new cases in 2020, colorectal cancer was the 7th most frequently diagnosed cancer, representing 9.4% of total cancer cases. Colorectal cancer is more common in men than women.
The highest colorectal cancer rates are found in Australia/New Zealand, Europe, and Northern America. This largely reflects risk factors like diets high in red or processed meats, obesity, smoking, and inadequate screening. Colorectal cancer caused about 935,000 deaths worldwide in 2020.
Trends in Colorectal Cancer Incidence
While colorectal cancer remains highly prevalent, its incidence has decreased in certain high-income countries over the past few decades. Experts cite increases in screening, particularly colonoscopies, that allow for the detection and removal of precancerous polyps before they turn cancerous. However, colorectal cancer rates are on the rise in certain countries with developing economies.
6. Leukemia
Leukemia starts in blood-forming cells in the bone marrow, causing large numbers of abnormal white blood cells to build up. In 2020, leukemia accounted for an estimated 607,000 new cancer cases worldwide, making up 3.1% of total cases. Leukemia is more common in males than females.
There are four main types of leukemia: acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML). Every type of leukemia can occur in adults; ALL and AML also develop in children. An estimated 409,000 deaths were caused by leukemia worldwide in 2020.
Trends in Childhood Leukemia Survival
Survival rates for childhood leukemia have increased dramatically in recent decades, now exceeding 90% in high-income countries. Improved treatments, like combination chemotherapy and targeted drugs, have revolutionized prognosis for children with leukemia.
5. Lung Cancer
Lung cancer develops in the lungs and is frequently caused by smoking. Approximately 2.2 million cases were diagnosed in 2020, making it the 5th most common cancer (11% of the total). Lung cancer is the leading cause of cancer deaths worldwide, resulting in about 1.8 million deaths in 2020.
There are two major types: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). NSCLC cases make up 80-85% of lung cancers. Since NSCLC grows and spreads slower than SCLC, it is often diagnosed at earlier stages with better prognosis.
Lung cancer rates have been falling in many Western countries due to declines in smoking rates. However, they continue to rise across certain regions like Eastern Asia and Africa.
5-Year Lung Cancer Survival Rates by Stage
| Stage | 5-Year Survival Rate |
|---|---|
| Localized (confined to primary site) | 61% |
| Regional (spread to lymph nodes) | 35% |
| Distant (metastasized) | 7% |
As shown in the table, lung cancer survival rates depend heavily on how early the cancer is diagnosed. This underscores the importance of screening for early detection in high-risk groups, like people with a history of heavy smoking.
4. Colon Cancer
Colon cancer develops in the longest portion of the large intestine. In 2020, there were approximately 1.9 million new colon cancer cases worldwide, accounting for 9.4% of total cancer cases. Colon cancer is slightly more prevalent in men than women.
Similar to colorectal cancer trends, colon cancer rates are highest in locations like Australia, New Zealand, Europe, and North America where risk factors like smoking, obesity, and red/processed meat consumption are most common.
There were approximately 935,000 colon cancer deaths worldwide in 2020, making it a leading cause of cancer mortality. Early detection through colonoscopy screening allows for the removal of precancerous growths and detection of colon cancer at more treatable stages.
5-Year Colon Cancer Survival Rates by Stage
| Stage | 5-Year Survival Rate |
|---|---|
| Localized | 91% |
| Regional spread | 74% |
| Distant metastasis | 15% |
As illustrated by the survival rate table, finding colon cancer early on greatly impacts the chance of treatment success. Screening methods like colonoscopies allow doctors to find and remove precancerous polyps as well as detect colon tumors at more treatable stages.
3. Rectal Cancer
Rectal cancer begins in the rectum, which connects the colon to the anus. Around 935,000 new rectal cancer cases were diagnosed worldwide in 2020. This equates to 4.8% of total cancer cases. Rectal cancer is slightly more common in males than females.
Similar to colon cancer, rectal cancer shows geographic variation with the highest incidences in locations like Australia/New Zealand, Europe, and North America. An estimated 416,000 deaths were caused by rectal cancer worldwide in 2020.
Many rectal cancers are thought to arise from adenomatous polyps in the rectum. Screening colonoscopies allow doctors to remove these polyps before they become cancerous, reducing risk.
Trends in Rectal Cancer Incidence
In contrast to the overall decline in colorectal cancer rates in many Western countries, rectal cancer incidences have been increasing in recent decades among adults under age 55. The exact reasons are unknown but potential factors include obesity, lack of physical activity, and changing diets/gut microbiomes.
2. Breast Cancer
Breast cancer originates in breast tissue and is the most commonly diagnosed cancer in women worldwide. In 2020, there were an estimated 2.3 million new cases of breast cancer, accounting for 11.7% of all cancer cases globally. Breast cancer rates among women are highest in locations like Australia/New Zealand, North America, and Western Europe.
While breast cancer remains common, death rates have been declining in many countries due to improvements in early detection and treatment. Still, breast cancer caused an estimated 685,000 deaths worldwide in 2020.
5-Year Breast Cancer Survival Rates by Stage
| Stage | 5-Year Survival Rate |
|---|---|
| Localized | 99% |
| Regional spread | 86% |
| Distant metastasis | 29% |
As the survival rates indicate, the stage at which breast cancer is detected has a huge impact on the chances of successful treatment and survival. That’s why early detection through regular mammogram screening is so critical.
1. Lung Cancer
Ranking as the most commonly diagnosed cancer worldwide is lung cancer, with around 2.2 million new cases in 2020 representing 11% of total cancer burden. Lung cancer is the leading cause of global cancer deaths, resulting in approximately 1.8 million deaths in 2020.
Cigarette smoking is the number one risk factor for lung cancer, causing the vast majority of cases. With tobacco consumption still high in certain world regions, lung cancer rates are on the rise in areas like Eastern Asia and Africa, while decreasing in some Western countries that have seen bigger smoking declines.
Non-small cell lung cancer accounts for 80-85% of lung tumors. Since it usually spreads slower than small cell lung cancer, NSCLC tends to be caught at earlier stages. Lung cancer screening through low-dose CT scans in high-risk individuals provides the best chance for early NSCLC detection.
Global Age-Standardized Incidence Rates for Most Common Cancers
| Cancer Type | Global Age-Standardized Incidence Rate (per 100,000 population) |
|---|---|
| Lung | 22.5 |
| Breast | 20.6 |
| Colon | 18.1 |
| Rectal | 9.2 |
| Prostate | 24.5 |
| Stomach | 11.1 |
| Liver | 10.2 |
| Non-Hodgkin lymphoma | 7.5 |
This table provides a summary overview of the global incidence rates for the most common cancer types, standardized for age. This gives a sense of the population-level impact of each cancer worldwide.
Conclusion
While cancer comes in many forms, certain types consistently emerge as the most prevalent worldwide each year. Based on GLOBOCAN estimates for 2020, the most commonly diagnosed cancers in order are lung, breast, colon, rectal, prostate, stomach, liver, non-Hodgkin lymphoma, esophageal, colorectal, leukemia, and stomach cancer.
Lung and breast cancers alone account for nearly one-quarter of all cancer cases globally. Certain cancers like prostate and colorectal are more specific to males versus females. There is also geographical variation among cancer rates based on regional differences in risk factors.
The most common cancers cause a disproportionate amount of deaths each year, largely due to high incidence and late-stage diagnosis. Public health strategies aimed at prevention, early detection, and effective treatment can help reduce the burden of the most prevalent cancer types worldwide.
