Girls being vaccinated for HPV to prevent cervical cancer
Cervical cancer vaccinations in Africa ©️ Shutterstock


Cancer is a leading cause of chronic-disease related death in the world, with around 10 million people dying from cancer every year. While the global burden of cancer is increasing, at least one-third of cancers are preventable, and many cases and deaths can be averted through prevention and early detection.

Fast Facts

  • Cancer is a leading cause of death in the world. Around 10 million people die from cancer a year.
  • Cancer is a term used for a group of diseases that can affect any part of the body. They’re characterised by rapid, abnormal cell growth that then spreads to other parts of the body.
  • The most common types of cancer are breast, lung, colon and rectum, prostate, stomach, and skin cancers.
  • Over 30% of cancers are preventable. Risk factors for cancer include tobacco, obesity, physical inactivity, infections, alcohol, environmental pollution, occupational carcinogens, UV radiation.  
  • Cancer can be prevented and controlled by implementing evidence-based strategies for cancer prevention, screening and early detection, treatment and palliative care.

What is cancer?

Cancer is a term used for a group of diseases that can affect any part of the body. These are also known as malignant tumours and neoplasms. Cancer is characterised by rapid abnormal cell growth, which then spreads to other parts of the body via a process called metastasis. A major cause of cancer death is when these abnormal cells form lumps in our vital organs.
Cancer kills 10 million people every year. While there are regional and sex differences, globally, the main types of cancer are:

  • Breast cancer (2.26 million cases and 685,000 deaths in 2020)
  • Lung cancer (2.21 million cases and 1.8 million deaths)
  • Colon and rectum cancer, including bowel cancer (1.93 million cases and 935,000 deaths)
  • Stomach cancer (1.09 million cases and 769,000 deaths)
  • Liver cancer (906,000 cases and 830,000 deaths)
  • Prostate cancer (1.41 million cases and 375,000 deaths)
  • Skin cancer (non-melanoma) (1.20 million cases and 57,000 deaths)

What are the risk factors for cancer?

Cancers are caused by a range of factors, however, between 30% and 50% of cancers can be prevented through strategies to reduce behavioural and dietary risk factors.

Tobacco use is responsible for around 22% of cancer deaths. Tobacco is smoked or chewed but is related to many other cancers beyond the lung or mouth. Tobacco contains at least 80 different cancer-causing agents and is a major risk factor for over 20 different types of cancer, cardiovascular and respiratory diseases. Over 80% of the 1.3 billion tobacco users worldwide live in low- and middle-income countries.

Alcohol consumption, even moderate consumption, can increase the risk of at least six types of cancers including bowel (colorectal), breast, mouth, pharynx, and larynx (mouth and throat), oesophageal, liver and stomach. Alcohol is estimated to have caused 4% of all cancer cases in 2020.

Unhealthy diets and nutrition and the food we eat are closely linked to some cancers. There is strong evidence to show that eating processed meats such as ham, bacon, salami, and sausages can cause bowel cancer. While diets high in red meat, salt or sugars are risk factors for some cancers and a range of noncommunicable diseases.

Overweight and obesity, where the body is carrying excess weight, are linked to an increased risk of developing 12 cancers. These include endometrial, breast, ovarian, prostate, liver, gallbladder, kidney, and colon.

Some infections are more likely to lead to cancer because viruses can make changes to a cell that can become cancerous. This includes human papillomavirus (HPV) infections, which cause around 70% of cervical cancers. Liver cancer and non-Hodgkin lymphoma can also be caused by the hepatitis B (HBV) and hepatitis C (HBC) virus.

Other modifiable risk factors are linked to the environment around us and our places of work. These include air pollution, exposure to manmade sources of radiation, and prolonged exposure to ultraviolet radiations from the sun and tanning beds which can also lead to melanoma and skin malignancies.

In addition to these modifiable risks, the risk of cancer is also related to genetics and age. This is because the longer someone lives, the more chance that they have been exposed to cancer-causing agents and the more time that genetic mutations can occur in their cells.

How can we prevent cancer?

Creating environments and societies that make it easier for people to adopt healthier behaviours and prevent cancers in the first place is the single most important thing we can do to reduce the global burden of cancers. This includes reducing exposures to risk factors such as tobacco, obesity, physical inactivity, infections, alcohol, environmental pollution, occupational carcinogens, and UV radiation. The rollout of vaccination programmes for vulnerable populations for HBV and HPV is also critical.

Reducing exposures to other carcinogens such as environmental pollution, occupational carcinogens and radiation could help prevent the global cancer burden.

Cancer Care

Improving access to quality cancer care, including screening, early detection, treatment, and palliative care is a critical part of improving the quality of life of people living with cancer and those around them – with the aim of reducing global deaths from cancer in most cases.

Screening, early detection and treatment

When identified early, cancer is more likely to respond to treatment leading to better survival outcomes, less morbidity, and less expensive treatment overall. For the mental health of people living with cancer, this is also very positive. Programmes that screen patients based on age and risk factors are critical interventions. For example, many of the most common high-impact cancers – breast, cervical, oral and colorectal cancers – lend themselves to affordable and accessible early detection through screening, with high potential for recovery if diagnosed at an early stage and appropriate treatment is provided.

Cancer treatment involves a series of interventions, including psychosocial support, surgery, radiotherapy, and chemotherapy aimed at curing the disease or prolonging life considerably while improving patients’ quality of life.

Palliative care

Palliative care is treatment/care given to patient to relieve their pain or suffering, making them more comfortable instead of trying to cure them. Often given in the final stages of cancer, palliative care offers people a better quality of life, for them and the people around them.

Access to pain relief is an urgent humanitarian need worldwide for children and adults with advanced cancers. According to the Worldwide Hospice Palliative Care Alliance, less than 10% of the overall need for palliative care is being met globally.

Cancer care gap

Inequities in access to these lifesaving services exist in all parts of the world. The main drivers of cancer care gaps are based on income, education, location and discrimination based on factors such as ethnicity, race, gender, sexual orientation, age, disability and lifestyle. The video below highlights the ageism care gap.



What’s more, the most disadvantaged groups are more likely to be exposed to cancer risk factors such as tobacco, unhealthy diets, and environmental hazards.

NCD Alliance founding organisation, the Union for International Cancer Control (UICC) celebrates World Cancer Day on 4 February every year. In 2022, they are inviting everyone to play their part in creating a cancer-free world under the ‘Close the Care Gap’ campaign, which is all about understanding and recognising the inequities in cancer care around the globe.

Policies to reduce the cancer burden

The World Cancer Declaration calls upon government leaders and health policymakers to significantly reduce the global cancer burden, promote greater equity, and integrate cancer control into the global health and development agenda.

Spearheaded by UICC, it sets out nine goals to be achieved by 2025 including – which align with global ambition of a 25% reduction in premature mortality from NCDs by the same year.

These include:

  • National cancer control plans (NCCPs) which identify national priorities and all activities that will take place to ensure the prevention and control of cancers and how civil society organisations, academics, UN agencies, international donors and appropriate private sector organisations will be involved to achieve this.
  • Tobacco control programmes which focus on reduction in consumption of tobacco products through taxes, smoke-free public spaces, regulations on plain packaging, advertising, and legal age limits for tobacco use.
  • Healthy diets promotion to reduce the number of people who are obese or overweight through taxation of sugary beverages, marketing bans and front of package labelling.
  • Vaccination programmes for Hepatitis B and Human Papillomavirus to reduce prevalence of related cancers.
  • Early detection of cancer initiatives that are well funded and work with different partners to improve awareness of the different signs and symptoms of common cancers, while investing in screening and diagnosis.
  • Improving access to essential medicines and technologies to ensure that every cancer patient has access to affordable and effective screening, treatment and care - including for palliative care.



This page was reviewed on 03/02/2022