Childhood cancer is cancer in a child of the ages 0–14 years.
Sometimes the definition includes adolescents between 15–19 years old.
An estimated 14,470 children and 5480 adolescents were diagnosed with cancer in the United States in 2022, and 1050 children and 550 adolescents will die of the disease.
More than 85% of childhood cancer victims, survive for at least five years.
It is estimated that childhood cancer has an incidence of more than 175,000 per year, and a mortality rate of approximately 96,000 per year, worldwide.
The most common types of cancer diagnosis from birth through 14 years of age include CNS tumors, such as medulloblastoma and glioma and acute lymphoblastic leukemia.
The most common types of cancer diagnosed in individuals 15 to 19 years of age include CNS tumors, thyroid cancer, Hodgkin lymphoma, and germ cell and gonadal tumors.
Other types of childhood cancer include: non-Hodgkin’s, lymphoma, acute myelogenous leukemia, bone and soft tissue sarcomas, neuroblastoma, Wilms tumor, retinoblastoma, and hepatoblastoma.
Treatment for childhood cancer may include: chemotherapy, radiation, surgery, targeted therapy, immunotherapy, and hematopoietic stem cell transplant.
In children aged 14 or younger non-Hodgkin lymphoma accounts of 5% of cancers, whereas adolescents age 15-19 years NHL accounts for 7% of malignancies.
Pediatric malignancies are defined as a complex process of physiological growth, arising from embryonic stem cells and their milieu.
A general feature of pediatric malignancies is an extremely low rate of mutation even for metastatic tumors in which a single gene aberration may be the sole recurrent event.
High mutation rates are not necessary for the genesis of pediatric cancers, which are driven mostly by epigenetic dysregulation.
Pediatric aggressive mature B-cell lymphomas are the most common non-Hodgkin’ lymphoma types in children, and include Burkitt lymphoma and diffuse large B-cell lymphoma.
Childhood cancer has a mortality of approximately 20% of cases.
Familial and genetic factors are identified in 5-15% of childhood cancer cases.
In <5-10% of cases of childhood cancer, there are environmental exposures and exogenous factors, such as prenatal exposure to tobacco, X-rays, or certain medications are risk factors.
For 75-90% of childhood cancers the causes remain unknown.
Risk factors of childhood cancer different from those seen in adult cancers include:
unique, exposures to environmental hazards.
Immature physiological systems to clear or metabolize environmental substances are
developmental windows in critical vulnerability.
A longer life expectancy in children avails for a longer time to manifest cancer processes with long latency periods, increasing the risk of developing some cancer types later in life.
Advanced parental age increases risk of childhood cancer offspring.
The most common cancers in children are leukemia (32%), brain tumors (18%), and lymphomas (11%).
The main brain and central nervous system tumors in children are: astrocytoma, brain stem glioma, craniopharyngioma, desmoplastic infantile ganglioglioma, ependymoma, high-grade glioma, medulloblastoma and atypical teratoid rhabdoid tumor.
Less common childhood cancer types are:
Neuroblastoma (6%, nervous system)
Wilms tumor (5%, kidney)Non-Hodgkin lymphoma (4%, blood)
Childhood rhabdomyosarcoma (3%, many sites)
Retinoblastoma (3%, eye)
Osteosarcoma (3%, bone cancer)
Ewing sarcoma (1%)
Germ cell tumors (5%)
Hepatoblastoma and hepatocellular carcinoma
Adolescent and young adult oncology (AYA) deals with the prevention, diagnosis, and treatment of cancer in AYA patients aged 13-30.
The survival rate for adolescents and young adults has remained stagnant.
Treating young adults with the same protocols used in pediatrics is more effective than adult oriented treatments.
Premature heart disease is a major long-term complication in adult survivors of childhood cancer.
Adult survivors are eight times more likely to die of heart disease than other people, and more than half of children treated for cancer develop some type of cardiac abnormality.
Survivors of childhood cancer are also at risk of developing adverse effects on the kidneys and the liver.
Anticancetb treatments and liver surgery may also increase the risk of adverse liver effects in childhood cancer survivors.
The greatest variation in childhood cancer incidence occurs when comparing high-income countries to low-income ones.
Cancer is the second most common cause of death among children between the ages of 1 and 14 years, exceeded only by accidents in the US.
Mortality is approximately 80%, or even 90% in the world’s poorest countries.
In many developed countries the incidence is slowly increasing.
Approximately 14,500 new cases of cancer diagnosed in children from birth to 19 years annually, and approximately 1800-1900 will die.
Globally more than 250,000 children are diagnosed with cancer annually.
Children, adolescents and young adults have a distinct set of cancers compared to adult patients.
Cancers rarely occur before age 20 years.
In adults most cancers are carcinomas and prognosis can be improved early detection.
In Pediatric tumors carcinomas are rare.
Most forms of childhood cancer appear to have been initiated in utero.
The common cancers in children include: leukemia, lymphoma, brain tumors, neuroblastoma, Wilms tumor’s, and sarcomas.
Being born with a birth defect is one of the strongest known risk factors for cancer in children.
Children with trisomy 21 have a 20 fold increase risk of acute lymphoblastic leukemia.
Children with chromosomal anomalies and non-chromosomal birth defects are at an increased risk of developing cancer.
With nonchromosomal birth defects children have a relative increased risk of cancer, although the absolute risk remains low at less than 1%.
Because of symptomatology in most cases of childhood cancer, diagnosis occurs in a relatively short time.
Approximately 80% of children on treatment for high-risk cancer experience fear, life-threatening or fatal side effects at some point during treatment.
Unlike cancers common in adults, childhood cancers are unlikely to be prevented by screening.
Childhood and adolescent cancer is much less amenable to prevention than many major cancers of adults, for which risk factors can be reduced or even eliminated.
Children with cancer are at risk for developing cognitive or learning problems, that may be related to brain injury stemming from the cancer itself, such as a brain tumor or central nervous system metastasis or from side effects of cancer treatments such as chemotherapy and radiation therapy.
Cognitive impairment is commonly noticed a few years after cancer treatment.