Cancer is a leading cause of death for children and adolescents around the world and approximately 300,000 children aged 0 to 19 years old are diagnosed with cancer each year. 
The most common categories of childhood cancers include leukemias, brain cancers, lymphomas and solid tumours, such as neuroblastoma and Wilms tumour. [1-2]
In high-income countries, more than 80% of children with cancer are cured, but in many low- and middle-income countries (LMICs) only about 20% are cured. [2-3]
Childhood cancer generally cannot be prevented or screened.
Improving outcomes for children with cancer requires early and accurate diagnosis followed by effective treatment.
Most childhood cancers can be cured with generic medicines and other forms of treatments including surgery and radiotherapy. Treatment of childhood cancer can be cost-effective in all income settings. 
Avoidable deaths from childhood cancers in LMICs result from lack of diagnosis, misdiagnosis or delayed diagnosis, obstacles to accessing care, abandonment of treatment, death from toxicity, and higher rates of relapse.
Childhood cancer data systems are needed to drive continuous improvements in the quality of care, and to drive policy decisions.
Cancer is a leading cause of death for children and adolescents worldwide. In high-income countries, more than 80% of children with cancer are cured, but in many LMICs, only 20% are cured [2-3].
The reasons for lower survival rates in LMICs include an inability to obtain an accurate diagnosis, inaccessible therapy, abandonment of treatment, death from toxicity (side effects), and excess relapse, in part due to lack of access to essential medicines and technologies addressing each of these gaps improves survival and can be highly cost-effective [2-3].
What causes cancer in children?
Cancer occurs in people of all ages and can affect any part of the body. It begins with genetic changes in a single cell that then grows out of control. In many cancers, this results in a mass (or a tumour). If left untreated, cancer generally expands, invades other parts of the body and causes death.
Unlike cancer in adults, the vast majority of childhood cancers do not have a known cause. Many studies have sought to identify the causes of childhood cancer, but very few cancers in children are caused by environmental or lifestyle factors. Cancer prevention efforts in children should focus on behaviours that will prevent the child from developing preventable cancer as an adult.
Some chronic infections are risk factors for childhood cancer and have major relevance in low- and middle-income countries. For example, HIV, Epstein-Barr virus and malaria increase the risk of some childhood cancers. Other infections can increase the child’s risk of developing cancer as an adult, so it is important to be vaccinated and other pursue other methods such as early diagnosis or screening to decrease chronic infections that lead to cancer, whether in childhood or later.
Current data suggest that approximately 10% of all children with cancer have a predisposition because of genetic factors. Ongoing research is needed to identify factors impacting cancer development in children.
Improving outcomes of childhood cancer
Because it is generally not possible to prevent cancer in children, the most effective strategy to reduce the burden of cancer in children is to focus on a prompt, correct diagnosis followed by effective therapy.
When identified early, cancer is more likely to respond to effective treatment and result in a greater probability of survival, less suffering, and often less expensive and less intensive treatment. Significant improvements can be made in the lives of children with cancer by detecting cancer early and avoiding delays in care. A correct diagnosis is essential to treat children with cancer because each cancer requires a specific treatment regimen that may include surgery, radiotherapy, and chemotherapy.
Early diagnosis consists of 3 components:
awareness by families and accessing care
clinical evaluation, diagnosis and staging (determining the extent to which a cancer has spread)
access to treatment
Early diagnosis is relevant in all settings and improves survival for many cancers.6 Programmes to promote early and correct diagnosis have been successfully used in countries of all income levels, often through collaborative efforts of governments, civil society, and non-governmental organizations, with vital roles played by parent groups. Childhood cancer is associated with a range of warning symptoms that can be detected by families and by trained primary health care providers.6
Screening is generally not helpful for childhood cancers. In some select cases, it can be considered in high-risk populations. For example, some eye cancers in children can be caused by a mutation that is inherited, so if that mutation is identified in the family of a child with retinoblastoma, genetic counselling can be offered and siblings monitored with regular eye examination early in life. Genetic causes of childhood cancers are relevant in only a handful of children with cancer. There is no high-quality evidence to support population-based screening programmes in children.
A correct diagnosis is essential to treat children with cancer because each cancer requires a specific treatment regimen that may include surgery, radiotherapy, and chemotherapy. Access to effective diagnosis, essential medicines, pathology, blood products, radiation therapy, technology and psychosocial and supportive care are variable and inequitable around the world.
However, a cure is possible for more than 80% of children with cancer, in most cases with inexpensive generic medications that are listed on the WHO List of Essential Medicines (EML). WHO EML for children, defined as those meeting the priority health care needs of the population, includes 22 cytotoxic or adjuvant medicines and 4 hormone treatments for childhood cancer. Children who complete treatment require ongoing care to monitor for cancer recurrence and to manage any possible treatment-related toxicity.
Palliative care relieves symptoms caused by cancer and improves the quality of life of patients and their families. Not all children with cancer can be cured, but relief of suffering is possible for everyone. Paediatric palliative care should be appropriately considered as a core component of comprehensive care starting when the illness is diagnosed and continued regardless of whether or not a child receives treatment with curative intent.7
Palliative care programmes can be delivered through community- and home-based care to provide pain relief and psychosocial support to patients and their families. Adequate access to oral morphine and other pain should be provided for the treatment of moderate to severe cancer pain, which affects more than 80% of cancer patients in the terminal phase.
In 2018, WHO launched the Global Initiative for Childhood Cancer with partners to provide leadership and technical assistance to support governments in building and sustaining high-quality childhood cancer programmes. The goal is to achieve at least 60% survival for all children with cancer globally by 2030. This represents an approximate doubling of the current cure rate and will save an additional one million lives over the next decade. The objectives are to:
Increase capacity of countries to deliver best practices in childhood cancer care
Prioritize childhood cancer and increase available funding at the national and global levels
WHO and the International Agency for Research on Cancer (IARC) collaborate with the International Atomic Energy Agency (IAEA) and other UN organizations and partners, to:
increase political commitment for childhood cancer diagnosis and treatment;
support governments to develop high-quality cancer centres and regional satellites to ensure early and accurate diagnosis and effective treatment for children with cancer;
develop standards and tools to guide the planning and implementation of interventions for early diagnosis, treatment and palliative and survivorship care inclusive of the needs of childhood cancers;
improve access to affordable and essential medicines and technologies;
support governments to safeguard families of children with cancer from financial ruin and social isolation as a result of cancer care.
This initiative is part of the implementation of the World Health Assembly Resolution Cancer Prevention and Control through an Integrated Approach (WHA70.12), which urges governments and WHO to accelerate action to achieve the targets specified in the Global Action Plan and 2030 UN Agenda for Sustainable Development to reduce premature mortality from cancer.
Steliarova-Foucher E, Colombet M, Ries LAG, et al. International incidence of childhood cancer, 2001-10: a population-based registry study. Lancet Oncol. 2017;18(6):719-731.
Gupta S, Howard SC, Hunger SP, et al. Treating Childhood Cancer in Low- and Middle-Income Countries. In: Disease Control Priorities, volume 3. http://dcp-3.org/chapter/900/treating-childhood-cancers-low-and-middle-income-countries
Howard SC, Zaidi A, Cao X, et al. The My Child Matters programme: effect of public-private partnerships on paediatric cancer care in low-income and middle-income countries. Lancet Oncol. 2018;19(5):e252-e266.
Zhang J, Walsh MF, Wu G, Edmonson MN, Gruber TA, et al. Germline Mutations in Predisposition Genes in Pediatric Cancer. N Engl J Med. 2015 Dec 10;373(24):2336-2346.