Childhood cancer is not a single disease, but includes a large number of diseases, with particular characteristics and behavior that is absolutely different from each other. However, all these diseases have a common denominator: they originate from the abnormal growth of a single cell or a group of them, which have the ability to invade both neighboring and distant organs.
In general, the most frequent types of childhood cancer can be divided into two main groups: hematological diseases (leukemias and lymphomas) and solid tumors.
Leukemia in children
Leukemia is a cancer of the blood that begins in the bone marrow, tissue found inside the bones that produces blood cells (red, white, and platelet cells). It is produced by the uncontrolled proliferation of cells called “blasts” (immature white blood cells), which are generated in the bone marrow, displacing the rest of the blood cells, so that the child presents symptoms of anemia (tiredness, paleness … ) and hemorrhages (bruises) and infections, among others. It is the most frequent childhood cancer and there are several. The most common in children are acute lymphoblastic leukemias.
What is the most common?
- Acute lymphoblastic leukemia (ALL) . It is the most common type of leukemia in children. It affects lymphocytes. A significant percentage of children with ALL are between 2 and 8 years old, but it can also appear at other ages.
- Acute myeloid or granulocytic leukemia. It usually occurs in adults, but when it appears in children, it occurs throughout childhood and adolescence. Malignant cells originate from the cells that give rise to neutrophils.
- Chronic myeloid leukemia. Chronic leukemias are rare in children. Its characteristic is the presence of a large number of immature neutrophils.
Lymphomas in children
Lymphomas are cancers that develop from the lymphatic system, which is part of the immune system. This lymphatic system is found in a series of organs such as the spleen, the thymus, the ganglia, the bone marrow; and other organs that contain lymphoid tissue such as the tonsils, skin, small intestine, and stomach. A lymphoma can develop in any of these organs. Lymphomas can be divided into Hodgkin Lymphoma and Non-Hodgkin Lymphoma.
Hodgkin’s lymphoma
It generally affects the peripheral lymph nodes, in people aged 10 to 30 years. Non-Hodgkin lymphoma is more common in children. It can also appear in the liver, spleen, nervous system, bone marrow, and lymph nodes.
More frequent solid tumors in children
The word tumor does not always imply the diagnosis of cancer. Some tumors are benign and therefore non-cancerous, while in others, the cells are very aggressive, causing malignant solid tumors. The most common in children are:
Tumors of the central nervous system
Brain tumors are classified and named for the type of tissue in which they develop. They constitute the second most frequent tumor in children. They can appear at any age in childhood and adolescence, although they are more frequent between 5 and 10 years of life. They can produce seizures, headaches, vomiting, irritability, behavioral disturbances, drowsiness, etc.
Neuroblastoma
It is a tumor that originates from sympathetic nerve cells from the neck to the pelvis. The most frequent location is the abdomen. It is a tumor that only develops in children, generally below the age of five. One of the most characteristic symptoms is the presence of a mass and abdominal pain, but it can also be accompanied by diarrhea and bone pain.
Wilms’ tumor
It is a malignant tumor that affects the cells of the kidneys. It generally occurs in children before the age of ten. The most frequent symptoms are the presence of an abdominal mass, fever, loss of appetite, presence of blood in the urine or abdominal pain.
Retinoblastoma
It is a malignant tumor of the retina. In almost half of the patients it is bilateral. Most often, this tumor develops in children younger than 5 years, although it can appear at any age.
Rhabdomyosarcoma
It is a type of soft tissue sarcoma that primarily affects muscle cells. Although it can occur in any muscular area, the most frequent locations are head and neck, pelvis and extremities. It occurs more frequently in males and in ages between 2 and 6 years.
Osteosarcoma
It is the most common form of bone cancer in children. They generally appear on the long bones of the arm (humerus) and leg (femur and tibia). It occurs between the ages of 10 and 25, and is more frequent in males.
Ewing’s sarcoma
It is another form of bone cancer. It affects a different part of the bone (the shaft or central part of the bone) and usually occurs in bones other than long bones and flat bones. Like osteosarcoma, it usually occurs between the ages of 10 and 25 and affects more males than females.