The types of cancers that develop in children are different from those that develop in adults. Lifestyle or environmental risk factors don’t play a role. Instead, it’s usually the result of DNA changes in cells that take place very early in life.
Because of major treatment advances, more than 80 % of children with cancer now survive five years or more. Still, cancer is the second leading cause of death in children younger than 15 years old, after accidents.
Cancers in children are sometimes hard to recognise because common illnesses or everyday bumps and bruises can mask the early warning signs.
Below is some brief information on the most common Childhood Cancers with links to more information on each:
Leukaemias (cancers of the bone marrow and blood), are the most common childhood cancers. Leukaemia accounts for about 35% of all childhood cancers.
The most common types in children are Acute Lymphocytic Leukaemia (ALL) and Acute Myelogenous Leukaemia (AML).
Leukaemia can cause bone and joint pain, fatigue, weakness, pale skin, bleeding or bruising, fever, weight loss, and other symptoms. Acute leukaemia can grow quickly, so needs to be treated (typically with chemotherapy) as soon as found.
Acute Lymphoblastic Leukaemia (ALL)
Acute Lymphoblastic Leukaemia, which is also referred to as Acute Lymphocytic Leukaemia, affects the lymphoid cells and gets worse very quickly if not caught and treated early on. Leukaemia begins in the bone marrow and spreads to the blood, and can then spread to the organs. Three out of four childhood leukaemia cases are ALL.
Acute Myeloid Leukaemia (AML)
is also known as Acute Non-lymphocytic Leukaemia, Acute Myeloblastic Leukaemia, Acute Granulocytic Leukaemia, or Acute Myelogenous Leukaemia. AML occurs when the myeloid stem cells produce too many immature white blood cells called myeloblasts (or myeloid blasts). Acute cancers get worse very quickly if they are not diagnosed and treated.
Brain Tumours and other nervous system tumours make up about 27 % of childhood cancers. Brain Tumours can be either primary (develop in the brain) or secondary (cancer from another part of the body spreads to the brain). A primary brain tumour occurs when abnormal cells form in the tissues of the brain. Brain tumours are the most common type of tumour that develops in children, and they can affect children of any age. Slightly more boys than girls develop brain tumours.
For more information see Brain Tumours
Neuroblastoma occurs when malignant cancer cells form in the specialised nerve cells of the sympathetic nervous system called neural crest cells. These cells are involved in the development of the nervous system and other tissues. Neuroblastoma may be present at birth, but generally presents in early childhood, before the age of 5 years. In most cases, by the time it is diagnosed the cancer has usually already spread to areas outside of the original site, often to the lymph nodes, bones, bone marrow, liver, and skin.
For more information see Neuroblastoma
Wilm’s Tumour is a cancer of the kidneys; it derives from specialised cells in the embryo known as metanephric blastema. These cells contribute to the development of the child’s kidneys while they’re in the womb and generally disappear at birth, but cells called nephrogenic rests can still be found in children with Wilms Tumour. Sometimes these cells begin to grow out of control, resulting in a mass of primitive, small, rapidly dividing cells called Wilms Tumour. This can affect only one kidney (unilateral) or both (bilateral).
Wilms’ Tumour is the third most common childhood cancer and accounts for 6-7% of childhood cancer cases. It is most prevalent in children between the ages of 3 and 4 years. It may spread to the liver, lungs, or nearby lymph nodes.
For more information see Wilm’s Tumour
Lymphoma starts in certain cells of the immune system called lymphocytes. These cancers affect lymph nodes and other lymph tissues, like the tonsils or thymus. They can also affect the bone marrow and other organs, and can cause different symptoms depending on where the cancer is growing. There are two main types of lymphoma:
Hodgkin Lymphoma, sometimes called Hodgkin disease, is rare in children younger than 5 years of age. This type of cancer is very similar in children and adults, including which types of treatment work best. Lymphomas can start anywhere within the lymphatic system, but Hodgkin’s Lymphoma generally starts in the lymph nodes in the neck and more often in teenagers between 15 and 19 years of age.
Non-Hodgkin Lymphoma is the more common lymphoma in children; it is uncommon in children under the age of 10, but when it does occur, it is more common in boys than in girls. NHL generally occurs more often in individuals between the ages of 10 and 20. The most common types of non-Hodgkin lymphoma in children are different from those in adults. These cancers often grow quickly and require intensive treatment, but they also tend to respond better to treatment than most non-Hodgkin lymphomas in adults.
Rhabdomyosarcoma is a soft tissue cancer that develops in the soft tissue of striated muscles, which are the muscles that are attached to bones and help the body to move. Rhabdomyosarcoma accounts for about 50% of soft tissue sarcomas in children and can begin in various places in the body.is mostly found in children under the age of 10 and occurs in more boys than girls. If the tumour occurs in the head or neck area it may spread to the brain or the fluid surrounding the spinal cord.
For more information see Rhabdomyosarcoma
Retinoblastoma is a type of eye cancer that develops in the light-sensitive lining of the eye, called the retina. Retinoblastoma can occur at any age but mainly occurs in children younger than 5 years of age and most often in those younger than 2.Retinoblastoma may occur in one or both eyes, but rarely spreads to other parts of the body. Although it is the most common eye tumour in children, it is a rare childhood cancer and accounts for about 3-4% of childhood cancers.
For more information see Retinoblastoma
Primary bone cancers (cancers that start in the bones) occur most often in older children and teens, but they can develop at any age. They account for about 3% of childhood cancers.
Primary bone cancer is different from metastatic bone cancer, which is cancer that starts somewhere else in the body and then spreads to the bones. Metastatic bone cancer is more common than primary bone cancer because many types of cancer (including many cancers in adults) can spread to the bones.
Two main types of primary bone cancers occur in children:
Osteosarcoma (also called Osteogenic Sarcoma) is the most common type of bone cancer and starts in the osteoblasts, which are the bone cells at the end of the long bones where new bone tissue forms as a young person grows. Osteosarcoma is most prevalent in teenagers, and most often forms in the bones near the knees of children and teenagers or in the bones surrounding the shoulder joints. Most osteosarcomas occur in the centre of the bone.
Ewing’s Sarcoma is a bone cancer (although it can also very rarely develop in the soft tissue) and is the second most common primary sarcoma that can develop in children, comprising 10-15% of childhood bone cancers. Ewing’s sarcoma is not very common in younger children; it occurs mostly in the teenage years and is slightly more prevalent in boys.