5 deadliest types of cancer worldwide

Cancer remains one of the leading causes of death worldwide, claiming millions of lives each year. Although advances in screening and treatment have improved outcomes for many patients, some cancers continue to cause a particularly high number of deaths globally.

The World Health Organization (WHO) estimates that nearly 10 million people died from cancer in 2024. Its latest global figures identify lung, colorectal, liver, breast and stomach cancers as the five leading causes of cancer deaths worldwide.

Here are the five deadliest types of cancer based on their estimated global death toll in 2024.

lung cancer

Lung cancer was the leading cause of cancer deaths worldwide in 2024, accounting for an estimated 1.86 million deaths.

The disease develops when abnormal cells grow uncontrollably in the lungs. Tobacco smoking is its main risk factor, although people who do not smoke can also develop lung cancer. Exposure to second-hand smoke, air pollution and certain workplace substances can also increase the risk.

Lung cancer is often diagnosed at an advanced stage, when treatment may be more difficult. Recognising symptoms and assessing people at high risk can help support earlier diagnosis.

Colorectal cancer

Colorectal cancer, which affects the colon or rectum, caused approximately 918,000 deaths worldwide in 2024.

The disease often begins with abnormal growths called polyps in the lining of the colon or rectum. Some polyps can develop into cancer over time, although not all do.

Risk factors include increasing age, family history, certain inherited conditions, smoking, alcohol consumption, physical inactivity and diets high in processed meat. Screening can help detect precancerous growths or cancer at an earlier stage.

Liver cancer

Liver cancer was responsible for an estimated 732,000 deaths globally in 2024.

Several conditions can increase the risk of developing the disease, including chronic hepatitis B or hepatitis C infection, cirrhosis and certain metabolic or liver diseases. Long-term heavy alcohol consumption can also contribute to liver damage and increase cancer risk.

Some people may have few noticeable symptoms during the early stages. Prevention and risk reduction can include hepatitis B vaccination, testing and treatment for viral hepatitis, and appropriate care for chronic liver disease.

Early detection of breast cancer can save lives [PikWizard]

Breast cancer caused approximately 694,000 deaths worldwide in 2024. Although it occurs predominantly in women, men can also develop the disease.

Breast cancer develops when cells in breast tissue grow abnormally. The risk increases with age, and other factors include family history, certain inherited genetic changes and hormonal and reproductive factors.

Possible warning signs include a new breast lump, changes in breast shape or size, skin changes and unusual nipple discharge. Not every breast change is cancer, but persistent or unusual changes should be assessed by a healthcare professional.

Early diagnosis and access to appropriate treatment can improve outcomes.

stomach cancer

Stomach cancer, also known as gastric cancer, caused an estimated 642,000 deaths worldwide in 2024.

The disease develops when cancerous cells form in the stomach lining. Infection with Helicobacter pylori (H. pylori), a bacterium that can cause chronic inflammation and stomach ulcers, is an important risk factor. Smoking and certain dietary and family-history factors can also contribute.

Early stomach cancer may cause few or nonspecific symptoms. Possible symptoms include persistent indigestion, abdominal discomfort, feeling full quickly, unexplained weight loss and difficulty eating. These symptoms can have many causes, but persistent or worsening problems should be medically assessed.

The number of deaths caused by these cancers highlights the importance of prevention, early diagnosis and access to effective treatment.

WHO identifies tobacco use, alcohol consumption, excess body weight, low fruit and vegetable intake, physical inactivity and air pollution among important cancer risk factors. Infections, including hepatitis viruses and human papillomavirus (HPV), also contribute to the cancer burden.

Not all cancers can be prevented, and having a risk factor does not mean a person will necessarily develop cancer. However, avoiding tobacco, receiving recommended vaccinations, addressing relevant infections, participating in appropriate screening programmes and seeking medical advice about concerning symptoms can help reduce risks or improve the chances of detecting cancer early.

Source: World Health Organization (WHO), Cancer fact sheet, updated July 3, 2026.