Pediatric Cancer Overview and Epidemiology

Study Notes

Cancer Overview

Cancer comprises diseases marked by uncontrolled cell division, resulting from disrupted cellular regulatory mechanisms.
Hallmarks of cancer cells include sustained proliferative signaling, evasion of growth suppressors, resistance to apoptosis, invasion, and metastasis.
Pathogenesis involves mutations in oncogenes, tumor suppressor genes, and DNA repair genes.

Pediatric Cancer Epidemiology

Childhood cancers are rare, yet they are the second leading cause of death in children following accidents.
Most prevalent pediatric cancers include:
- Leukemia (30%)
- Brain and CNS tumors (26%)
- Lymphomas (8%)
In 2020, childhood cancers represented 5.4% of all cancers in Saudi Arabia.

Leading Pediatric Cancers in Saudi Arabia (2020)

Top cancers among Saudi children:
- Leukemia (30.8%)
- Brain CNS tumors (16.7%)
- Hodgkin’s lymphoma (16.3%)
- Bone tumors (6.8%)

Age and Race Variations

Leukemias are more frequent in young children (ages 1-4).
Lymphomas are more common in adolescents (ages 15-19).
Higher leukemia rates are observed in Hispanic and American Indian/Alaska Native children.
Elevated brain/CNS tumor rates occur in White and American Indian/Alaska Native populations.

Differences Between Pediatric and Adult Cancers

Type of Cancer: Pediatric cancers are mostly hematologic (leukemia, lymphoma) or embryonal (e.g., neuroblastoma, Wilms' tumor), while adult cancers predominantly consist of carcinomas (e.g., lung, breast).
Genetic Mutations: Pediatric cancers often involve developmental genetic mutations, contrasting with accumulated DNA damage in adults.
Response to Treatment: Pediatric cancers show higher chemotherapy responsiveness and cure rates, unlike adults who may develop treatment resistance.
Prognosis: Children typically have better prognoses due to fewer comorbidities compared to adults.
Treatment Toxicity: Pediatric treatment results in long-term consequences (growth issues, secondary cancers), while adults face more immediate short-term toxicities.

Cancer Risk Factors in Pediatrics

Genetic Predisposition: Familial syndromes significantly raise the risk of developing cancer in children.
Environmental Factors: While environmental influences are less impactful in pediatric cancers than in adults, radiation exposure (e.g., from prior treatments) is a notable risk for leukemia, brain tumors, osteosarcoma, and thyroid cancer.

Major Genetic Syndromes Linked to Childhood Cancer

Down Syndrome (Trisomy 21): Associated with Acute Myeloid Leukemia (AML) and Acute Lymphoblastic Leukemia (ALL).
Li-Fraumeni Syndrome (TP53 mutation): Links to multiple cancers, including sarcomas, breast cancer, brain tumors, and leukemia.
Beckwith-Wiedemann Syndrome: Associated with Wilms' tumor and hepatoblastoma.
Neurofibromatosis: Linked to optic gliomas and CNS tumors.
Retinoblastoma (RB1 mutation): Connected to retinoblastoma and osteosarcoma.
Fanconi Anemia: Raises risk for leukemia and solid tumors.
Ataxia-Telangiectasia: Tied to leukemia and lymphoma.
WAGR Syndrome: Associated with Wilms' tumor and other conditions.

Description

This quiz covers the essential aspects of pediatric cancer, including its definition, prevalence, and leading types among children. It explores the mechanisms of cancer development and the demographic variations affecting childhood cancer incidences, with specific statistics from Saudi Arabia. Test your knowledge on childhood cancer types and their impact on health.