Childhood leukemia: causes, symptoms and treatments
Leukemia is the most common cancer in children. This type of cancer is characterized by the high production of abnormal white blood cells. What are the different types of childhood leukemia? What are the symptoms ? Are there any risk factors? What are the treatments ? Answers.
Leukemia in France
In France, almost a third of new cases of cancer diagnosed in children under 15 are leukemia. There are 150 to 200 cases detected each year.
Leukemia occurs when the body makes large amounts of abnormal (or immature) white blood cells. Symptoms, causes, and treatments depend on the type of leukemia.
The different types of leukemia
Leukemia is a disease of the white blood cells, the blood cells that fight infections. White blood cells are divided into three categories: lymphocytes, monocytes and polymorphonuclear cells.
Two criteria are taken into account to distinguish the different leukaemias: the nature of the abnormal cells and their evolution. Thus, we speak of acute leukemia when they appear suddenly and chronic leukemia when they develop gradually.
Acute leukemia
Acute leukemias are the most frequent forms in children since they are responsible for 90% of childhood leukemia, we distinguish between acute lymphoblastic (or lymphoid) leukemia and acute myeloblastic (or myeloid) leukemia. As the name suggests, they do not affect the same type of white blood cell. Acute lymphoblastic leukemias affect lymphocytes and acute myeloblastic leukemias affect monocytes and polymorphonuclear cells.
Lymphoblastic leukemia is the most common form in children (85% of cases).
Chronic leukemia
Chronic leukemias are rarer than acute leukemias. There are about 20 to 30 new cases per year in children. Their development is slower than acute leukemia. Among them are chronic myeloid leukemia (CML) and juvenile myelomonocytic leukemia (JML).
What are the symptoms of childhood leukemia?
Acute leukemia
In acute leukemia, symptoms come on quickly after the disease sets in.
The main symptoms are:
paleness, fatigue and / or increased heart rate due to low red blood cells, also called anemia.
bleeding from the gums or nose, as well as the appearance of unexplained bruising due to the drop in the level of platelets (the blood cells that block bleeding). These bleeds can be serious if they reach the brain or digestive tract.
unexplained fever, sore throat that persists or gets worse. These symptoms are a consequence of the decline in mature white blood cells. This increases the risk of infection which can be serious. Patients with leukemia may also have other symptoms related to the involvement of leukemia cells in the organs:
bone or abdominal pain.
swollen glands.
enlargement of the spleen or liver.
swollen gums.
Chronic leukemia
In chronic leukemia, the sick child can remain asymptomatic for several years due to the slow progression of the disease.
For example, chronic myelogenous leukemia (CML) can be suspected when a blood test shows the presence of many young bone marrow cells in the blood. Juvenile myelomonocytic leukemia (JML) can be suspected in the presence of a characteristic rash, xanthomas. It is a benign skin or subcutaneous tumor that is yellow or yellow-orange in color.
How to treat leukemia in children?
The treatment to be implemented depends on each case. It will depend on the type of leukemia, the child’s age, its overall health, the response to treatment, the presence of leukemia cells in important organs such as the brain or the spinal cord.
The main treatment for childhood leukemia is chemotherapy, and more specifically the combination of several chemotherapy drugs. Radiation therapy may also be considered if the cancer reaches areas that could be targeted by this type of treatment. It consists of destroying cancer cells with rays or high energy particles.
A bone marrow transplant (a substance found inside the bones and which produces the various blood cells) can also be offered when it is damaged by the disease or by treatments (including chemotherapy).
Other treatments are also possible:
immunotherapy: treatment that strengthens the immune system to better fight cancer.
targeted therapy: the administration of drugs that target specific molecules present in cells. cancerous to stop the spread of cancer.
Stem cell transplant: after destroying all the cells in the bone marrow with chemotherapy, healthy stem cells are transplanted to replace those that have been destroyed.
The duration of treatment for acute lymphoblastic leukemia (the most common form in children) is on average 2 to 3 years.
Childhood leukemia: are there any risk factors?
Some risk factors have been identified even if we cannot, to date, establish a cause and effect link between a specific risk factor and the onset of the disease.
Genetic risk factors
Certain chromosomal abnormalities increase the risk of leukemia. It is estimated that children with Down’s syndrome are 21 times more likely to develop leukemia compared to other children. Other genetic diseases increase the risk of leukemia in children: the familial syndrome of so-called “Li-Fraumeni” cancer, neurofibromatosis, Fanconi’s disease, certain immune deficiencies, ataxia-telangiectasia.
Non-genetic risk factors
Exposure to environmental contaminants and certain treatments could produce genetic alterations that may increase the risk of leukemia:
ionizing radiation.
pesticides.
benzene.
chemotherapy.
Exposure to high and very high voltage power lines is also suspected to increase the risk of childhood leukemia. Studies are currently underway to establish or not this link.
Finally, the exposure of pregnant women to organic solvents and pesticides as well as the consumption of alcohol during pregnancy could also increase the risk of leukemia in the unborn child.