Typically, the cause of childhood cancer is unknown and the factors that trigger cancer in kids are usually different from those that cause cancer in adults. For example, we know that smoking and certain exposure to environment toxins can result in cancer in adults. This is rarely the cause of cancer in children. In some cases, there may be genetic conditions that put a child at an increased risk of having cancer, such as Down syndrome. In addition, those who've previously had chemotherapy or radiation treatment are at an increased risk for a secondary cancer. In most cases, however, childhood cancers arise from non-inherited changes in the genes of growing cells. Because these errors occur randomly, there's no effective way to prevent them.
There are three major types of childhood cancers:
Cancer of the Blood – Leukemia
Leukemia, a cancer of the blood, is the most common childhood cancer, accounting for more than 1/3 of all pediatric cancers. Leukemia cells are abnormal immune blood cells that are not functioning properly and crowd out healthy blood cells. The main components of our blood, produced in the bone marrow, include red blood cells, platelets and white blood cells. Red blood cells carry oxygen and nutrients through the body, while white blood cells fight germs and infection, and platelets help stop bleeding. Types of leukemia include:
Acute Lymphoblastic Leukemia (ALL) - 4 out of 5 children who have Leukemia will have ALL
Acute Myelogenous Leukemia (AML) – About 1 in 5 children who have Leukemia will have AML
Chronic Myeloid Leukemia (CML) – Only about 1 in 50 children who have Leukemia will have CML
Juvenile Myelomonocytic Leukemia (JMML) – Only about 1 in 100 children who have Leukemia will have JMML, mostly affecting children aged 4 and younger.
Cancer of the Lymphatic System - Lymphoma
Lymphoma is a cancer of the lymphatic system. Under normal circumstances, the body’s immune system—consisting of immune cells—finds foreign or abnormal cells and attempts to destroy them. The immune cells are stored in lymphoid tissues in the body and are called lymphocytes. When a child has lymphoma, his immune system may not work properly to protect the body, and the abnormal immune cells crowd out the healthy cells in the immune system. Types of lymphomas include:
Hodgkin Lymphoma – About 4 out of every 10 children who have Lymphoma will have Hodgkin Lymphoma
Non Hodgkin Lymphoma (NHL) – About 6 out of every
10 children who have Lymphoma will have Non Hodgkin Lymphoma. There are
more than 12 types of Lymphomas that can be diagnosed in children and
teenagers. The most common types include:
- Burkitt Lymphoma
- Large B Cell Lymphoma
- Lymphoblastic Lymphoma
- Anaplastic Large Cell Lymphoma.
Cancer of the Bone, Organs or Tissues - Solid Tumors
A solid tumor is a group of abnormal cells stuck together. Tumors can develop in many parts of the body, including the brain, kidneys, liver and bones. These sick cells crowd out healthy cells and keep them from doing their job. Types of solid tumor cancers include:
Brain and Spinal Cord Tumors, also known as Central Nervous System (CNS) Tumors
– CNS tumors are the most common solid tumors in children, with about 1
in 5 children with cancer being diagnosed with a CNS tumor. Types of
CNS tumors include:
- Choroid Plexus Tumor
- Glioma (including Astrocytoma, Ependymoma, and Oligodendroglimoa)
- Germ Cell Tumors – Germ cell tumors are rare, with only about 3 or 4 of every 100 children being diagnosed with a germ cell tumor. They can also be benign or malignant when diagnosed.
Kidney Cancer – About 6 of every 100 children with cancer will be diagnosed with Kidney Cancer. Types of Kidney Cancer include:
- Wilms Tumor, also known as Nephroblastoma
- Renal Cell Carcinoma
- Clear Cell Sarcoma of the Kidney.
Liver Cancers – Only about 1 or 2 out of every 100 children with cancer will be diagnosed with Liver Cancer. Types of Liver Cancer include:
- Hepatocellular Carcinoma (HCC).
- Melanoma – Fewer than 1 in 100 children with cancer will have melanoma.
- Neuroblastoma – About 7 out of every 100 children with cancer will have Neuroblastoma. It is uncommon in older children and teenagers, usually occurring in infants and young children.
- Retinoblastoma - About 3 out of every 100 children with cancer will have Retinoblastoma, more often seen in infants and young children under 6 years of age.
Soft Tissue and Bone Sarcomas – About 12 out of every 100 children with cancer will have a sarcoma. Types of Sarcomas include:
- Osteosarcoma (also called Osteogenic Sarcoma)
- Ewing Sarcoma
- Non-rhabdomyosarcoma Soft Tissue Sarcomas
- Desmoplastic Small Round Cell Tumor
- Desmoid Tumors (also called Demoid Fibromatosis).
- Thyroid Cancer – Rare in children with only about 1 in 100 children with cancer being diagnosed with Thyroid Cancer. Also more common in teenagers than in younger children.
National Cancer Institute. A Snapshot of Pediatric Cancers
http://www.cancer.gov/researchandfunding/snapshots/pediatric. Accessed December 23, 2013