What are the most common types of cancer in children?

Most Common Types of Cancer in Children

The most common pediatric cancers are leukemias (30-40%), followed by central nervous system tumors (20%), and lymphomas (12%), with neuroblastoma, retinoblastoma, and tumors of soft tissues, bones, and gonads comprising the remainder of cases. 1

Leukemias

• Leukemias are the most common childhood malignancy, accounting for approximately 30-40% of all pediatric cancers 1
• Acute lymphoblastic leukemia (ALL) is the predominant type, representing about 75% of all childhood leukemias 2
• Acute myeloid leukemia (AML) is less common but has a poorer prognosis with a 5-year relative survival rate of only 26.4% 2
• Less common forms include chronic myeloid leukemia (CML) and juvenile myelomonocytic leukemia (JMML) 1
• Early symptoms may be nonspecific and similar to viral infections, but persistent vague symptoms accompanied by abnormal bleeding, bone pain, lymphadenopathy, or hepatosplenomegaly should raise suspicion 3

Central Nervous System (CNS) Tumors

• CNS tumors are the second most common pediatric malignancy, accounting for approximately 20% of all childhood cancers 1, 3
• They are the leading cause of cancer-related death in children 4
• The most common types include:
  • Astrocytomas (9.6% of all childhood cancers) 2
  • Gliomas, which are often located in the brain stem and may be difficult to biopsy 2
  • Medulloblastomas, which are the predominant embryonal tumors 4
• Presenting symptoms may include signs of elevated intracranial pressure, neurological abnormalities, and seizures 3
• According to the Central Brain Tumor Registry of the United States, the incidence rate of primary CNS tumors in children <20 years was 6.23 per 100,000 population between 2014 and 2018 4

Lymphomas

• Lymphomas represent approximately 12% of childhood cancers 1
• They typically present as one or more painless masses, often in the neck, with possible systemic symptoms such as fever and weight loss 3
• Hodgkin's disease most commonly presents as the nodular sclerosing subtype (56% of cases) 2
• Non-Hodgkin's lymphoma includes Burkitt's and Burkitt-like disease, which accounts for about one-third of cases and has a notably high male-to-female ratio of 5.7:1 2

Neuroblastoma

• Neuroblastoma accounts for about 6.6% of childhood cancers 2
• It is the most common extracranial solid tumor and the most common intra-abdominal solid tumor in children 5
• These tumors arise from sympathetic nervous tissue anywhere in the body but most commonly develop in the abdomen 3
• Clinical presentation depends on the local effects of the tumor and any metastases 3

Wilms' Tumor (Nephroblastoma)

• Wilms' tumor represents approximately 6.4% of childhood cancers 2
• It typically presents as an abdominal mass and may be accompanied by hypertension, hematuria, and abdominal pain 3
• Almost 80% of children with Wilms' tumor can be treated successfully with modern diagnostic and therapeutic approaches 4

Other Important Pediatric Cancers

• Retinoblastoma: A cancer of the eye that often has genetic implications 6
• Rhabdomyosarcoma: The most common histologic type of soft tissue sarcoma, accounting for 51% of all soft tissue sarcomas in children 2
• Bone tumors: Often first detected when trauma appears to cause pain and dysfunction disproportionate to the injury 3

Epidemiology and Risk Factors

• Childhood cancer has an annual incidence of about 150 new cases per 1 million U.S. children 3
• Cancer is the second leading cause of death in children older than 3 months 4
• From 1975-1978 to 1987-1990, cancer among white children increased slightly from 12.8 to 14.1 per 100,000 7
• Well-established environmental causes include radiation, chemotherapeutic agents, and diethylstilbestrol 7
• Suspected risk factors include electromagnetic fields, pesticides, and some parental occupational exposures 7
• Children with certain genetic conditions (such as Down syndrome) have an increased risk of developing cancer 3

Advances in Treatment

• Pediatric cancer survival has improved significantly due to better understanding of underlying genetic aberrations 6
• Genetic features are increasingly used for risk stratification and to identify novel pathways for targeted therapy 6
• A multidisciplinary approach involving pediatric oncologists, radiation oncologists, pathologists, neuroradiologists, and neurosurgeons is strongly encouraged for optimal outcomes 4