Understanding Childhood Cancers: A Comprehensive Guide for Parents and Caregivers

Learning that a child has cancer is a moment no parent ever anticipates. It’s a diagnosis that throws families into uncharted territory, filled with questions, anxieties, and an urgent need for information. Affecting around 400,000 children and adolescents aged 0-19 globally each year, childhood cancers are a leading cause of death by disease in this age group.

This blog provides you with clear, accurate, and empathetic information about the types of childhood cancer, helping you navigate this challenging journey with greater understanding and confidence. This guide will cover the most common childhood cancers, discuss the difference between adult and childhood cancers, explore cancer in children symptoms by type, and touch upon survival rates for childhood cancer types, and childhood cancer types by age.

The Unique Landscape of Childhood Cancers

First, it’s crucial to understand that pediatric cancer types are often distinctly different from those seen in adults. While adult cancers frequently originate in organs and are linked to lifestyle and environmental factors over many years, childhood cancers more commonly involve tissues like blood, bone marrow, lymph system, nerves, and bones. The causes of most childhood cancers remain unknown, with very few being linked to environmental, lifestyle or genetic factors. This means that, unlike adult cancers, childhood cancers generally cannot be prevented through lifestyle changes or identified through screening as done in the general population.

What Types of Cancer Affect Children? An Overview

When asked, “How many types of cancer are there in children?”, the answer is that there are dozens, with many more subtypes. However, certain types of cancer in children are more prevalent. Here’s a breakdown of the most common childhood cancers:

1. Leukemias: The Most Frequent Childhood Cancer

Leukemia in children is the most common childhood cancer, accounting for approximately one-third of all pediatric cancer diagnoses. This is a cancer of the blood and bone marrow, where the body produces abnormal, immature white blood cells (lymphocytes or myeloblasts) that can’t fight infection effectively. These cells crowd out healthy blood cells, leading to symptoms like fatigue, infections, easy bruising, and bone pain.

The main types of leukemia in children include:

• Acute Lymphoblastic Leukemia (ALL): Roughly three-quarters of all childhood leukemias are ALL, involving the rapid growth of abnormal lymphoblasts.
• Acute Myeloid Leukemia (AML): This type involves the abnormal growth of myeloblasts and monoblasts.

Early detection and aggressive treatment have led to remarkable improvements in survival rates for childhood cancer types like ALL, with over 90% of children achieving remission.

2. Brain and Central Nervous System (CNS) Tumors: The Second Most Common

Brain tumors in children are the second most common cancers in children and adolescents. These are masses of abnormal cells that grow in the brain or spinal cord. The symptoms of childhood brain tumors can vary widely depending on the tumor’s location and size, and may include headaches (often with morning vomiting), nausea, vision changes, dizziness, seizures, or problems with walking or balance.

There are many types of brain tumors in children, including:

• Astrocytomas: Can be low-grade (slow-growing) or high-grade (aggressive).
• Medulloblastomas: Fast-growing tumors that often occur in the cerebellum.
• Ependymomas: Arise in the lining of the brain’s ventricles.
• Brain-stem gliomas: Occur in the brainstem, controlling vital functions.

Treatment for brain tumors in children often involves surgery, chemotherapy, and/or radiation therapy.

3. Lymphomas: Cancers of the Immune System

Lymphomas are the third most common childhood cancers. These cancers develop in the lymph system, a part of the body’s immune system that includes lymph nodes and other lymphoid tissues like the tonsils and thymus. Symptoms of pediatric lymphoma can include swollen lymph nodes (especially in the neck, armpit, or groin), fever, night sweats, weight loss, and fatigue.

The primary pediatric cancer list for lymphomas includes:

• Hodgkin Lymphoma (HL): More common in adolescents and typically presents with gradual symptoms.
• Non-Hodgkin Lymphoma (NHL): Tends to grow more rapidly and is often more common in younger children.

Survival rates for childhood cancer types like Hodgkin lymphoma are very high with modern treatments.

4. Neuroblastoma: A Cancer of Immature Nerve Cells

Neuroblastoma is a solid tumor that forms from immature nerve cells. It’s the most common cancer in babies and young children, usually diagnosed before the age of 5. It often arises in the adrenal glands (located above the kidneys) but can also form in nerve tissue along the spine in the neck, chest, or abdomen. Symptoms can vary widely depending on the tumor’s location and whether it has spread.

5. Wilms’ Tumor: A Kidney Cancer

Also known as nephroblastoma, Wilms’ tumor is the most common type of kidney cancer in children. It typically affects children between the ages of 2 and 5. It often presents as a lump or swelling in the abdomen, sometimes accompanied by fever, pain, or nausea. Early detection often leads to high cure rates.

6. Rhabdomyosarcoma: Soft Tissue Sarcoma

Rhabdomyosarcoma is a type of soft tissue sarcoma that originates in cells that normally develop into skeletal (voluntary) muscles. It can occur almost anywhere in the body, with common sites including the head and neck, urinary/reproductive organs, or limbs. Symptoms might include a lump or swelling, sometimes with pain, that interferes with normal body function.

7. Retinoblastoma: Eye Cancer

Retinoblastoma is a rare cancer of the retina, the light-sensitive lining at the back of the eye. It usually affects children under five years old. Key signs of retinoblastoma often include an unusual white reflection in the pupil (sometimes visible in flash photographs), a squint, a change in iris colour, or a red/inflamed eye. Early diagnosis is crucial for saving both vision and life.

8. Bone Cancers: Osteosarcoma and Ewing Sarcoma

Bone cancers, specifically osteosarcoma and Ewing sarcoma, are more common in older children and teenagers.

• Osteosarcoma: The most common primary bone cancer, often arising during puberty’s growth spurt, frequently near the knee or shoulder. Symptoms include persistent bone pain and swelling.
• Ewing Sarcoma: A less common but aggressive bone cancer that often affects the pelvic bones, ribs, or long bones of the arms and legs. It also causes pain and swelling.

Rare Childhood Cancers

While the above constitute the most common cancers in children, other rare childhood cancers exist, such as liver tumors (e.g., hepatoblastoma), germ cell tumors (arising from reproductive cells), and Langerhans Cell Histiocytosis (LCH). These, while less common, also require specialized care from multidisciplinary teams.

Childhood Cancer Symptoms: What to Look For

Recognizing cancer in children symptoms by type can be challenging because they often mimic common childhood ailments. However, any persistent or worsening symptom warrants medical attention. The Childhood Oncology Group uses the acronym CHILDCANCER as a helpful guide:

• Continued, unexplained weight loss
• Headaches, often with early-morning vomiting
• Increased swelling or persistent pain in bones, joints, back, or legs
• Lump or mass, especially in the neck, chest, armpits, belly, or pelvis
• Development of excessive bruising, bleeding, or a rash
• Constant, frequent, or persistent infections
• A whitish color behind the pupil of the eye
• Nausea that persists, or vomiting without nausea
• Constant tiredness (fatigue) or noticeable paleness (pallor)
• Eye or vision changes that occur suddenly and persist
• Recurring or persistent fevers not associated with common illnesses

Childhood Cancer Types by Age

The incidence of specific pediatric cancer types can vary by age group:

• Infants (0-1 year): Neuroblastoma and retinoblastoma are more common. Leukemias also occur.
• Young Children (1-4 years): Leukemias (especially ALL) and Wilms’ tumor are frequently diagnosed.
• Children (5-9 years): Brain tumors and leukemias remain common.
• Adolescents (10-19 years): Bone cancers (osteosarcoma, Ewing sarcoma) and lymphomas become more prevalent.

Difference Between Adult and Childhood Cancers

Understanding the difference between adult and childhood cancers is vital for appropriate treatment:

1. Origin: Adult cancers often arise in organs (lung, breast, colon), while childhood cancers typically affect tissues like blood, bone, and lymph.
2. Causes: Adult cancers are frequently linked to lifestyle and environmental factors. Most childhood cancers have no known cause and are not preventable.
3. Genetics: While genetic mutations drive both, specific genetic changes in childhood cancers are often different from those in adult versions of similar cancers. Inherited genetic predispositions play a role in a small percentage of childhood cases.
4. Treatment Response: Children often respond better to more intensive treatments and are more resilient to side effects in the short term, though they face unique long-term effects.
5. Treatment Approach: Children are almost always treated at specialized children’s cancer centers by multidisciplinary teams of pediatric oncologists, surgeons, radiation oncologists, nurses, and supportive care specialists.

Survival Rates for Childhood Cancer Types

The good news is that advancements in treatment have dramatically improved survival rates for childhood cancer types. In high-income countries with access to comprehensive care, more than 80% of children with cancer are cured, a significant increase from 58% in the mid-1970s. However, this figure is starkly lower in low- and middle-income countries.

While overall survival is high, it’s important to remember that survival rates for childhood cancer types vary. For example, the 5-year survival rate for ALL is now over 90%, but for some aggressive brain tumors, it remains much lower. These statistics are general; each child’s prognosis is unique and depends on many factors, including the specific cancer type and stage, and response to treatment.

The Importance of Early Diagnosis and Specialized Care

Given that childhood cancers cannot generally be prevented, the most effective strategy to improve outcomes is prompt and accurate diagnosis followed by effective, evidence-based therapy in specialized centers. If you notice any persistent, unusual symptoms in your child, consulting your pediatrician without delay is crucial. Trust your instincts as a parent.

Moving Forward: Hope and Support

A cancer diagnosis is overwhelming, but it’s important to remember that significant progress has been made in treating childhood cancers. With ongoing research, improved access to care, and the dedication of pediatric oncology teams, more children are surviving and thriving. Support for families, including emotional and psychosocial care, is a vital part of the journey.

Contact Cancer Rounds team for detailed evaluation and to connect with the leading pediatric oncologist in India and abroad. Also, you get end-to-end assistance for treatment along with financial guidance.