Leukemia in Children
Leukemia is a type of cancer that affects the blood and bone marrow. In children, the most common type of leukemia is acute lymphoblastic leukemia (ALL), which is a cancer of the white blood cells.
ALL occurs when abnormal white blood cells (lymphoblasts) grow and divide rapidly, crowding out healthy blood cells and causing symptoms such as fatigue, weakness, fever, and easy bruising or bleeding. ALL can also cause bone pain, swollen lymph nodes, and other symptoms, depending on the stage of the disease.
Types of blood cells
There are three main types of blood cells: red blood cells, white blood cells, and platelets.
- Red blood cells (RBCs) – Red blood cells, also known as erythrocytes, are responsible for carrying oxygen from the lungs to the body’s tissues and transporting carbon dioxide from the tissues back to the lungs to be exhaled. RBCs contain hemoglobin, a protein that binds to oxygen and gives blood its red color.
- White blood cells (WBCs) – White blood cells, also known as leukocytes, are a crucial part of the immune system and play a role in defending the body against infections and diseases. There are several types of white blood cells, including lymphocytes, neutrophils, monocytes, eosinophils, and basophils. Each type of white blood cell has a specific function in the immune response.
Leukemia in Children
3. Platelets – Platelets, also known as thrombocytes, are cell fragments that help with blood clotting. They are involved in the formation of clots at the site of an injury to stop bleeding. Platelets also release chemicals that promote healing and repair damaged blood vessels.
All three types of blood cells are produced in the bone marrow, the spongy tissue inside bones. They are carried throughout the body in the blood vessels, delivering oxygen and nutrients to the tissues and removing waste products for elimination from the body.
Types of Leukemia in Children
There are several types of leukemia that can occur in children, but the two most common types are acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML).
- Acute lymphoblastic leukemia (ALL) – This is the most common type of leukemia in children, accounting for about 75% of all cases. ALL occurs when abnormal white blood cells (lymphoblasts) grow and divide rapidly, crowding out healthy blood cells and causing symptoms such as fatigue, weakness, fever, and easy bruising or bleeding.
- Acute myeloid leukemia (AML) – AML is a type of leukemia that occurs when abnormal myeloid cells grow and divide rapidly in the bone marrow. AML is less common in children than ALL, accounting for about 20% of all childhood leukemia cases. Symptoms of AML can include fatigue, fever, bone pain, easy bruising or bleeding, and other symptoms similar to those of ALL.
Less common types of leukemia that can occur in children include –
- Chronic myeloid leukemia (CML) – CML is a rare type of leukemia that occurs when abnormal myeloid cells grow and divide in the bone marrow.
- Chronic lymphocytic leukemia (CLL) – CLL is a rare type of leukemia that occurs when abnormal lymphocytes grow and divide in the bone marrow.
- Juvenile myelomonocytic leukemia (JMML) – JMML is a rare type of leukemia that occurs in young children, typically before the age of 4. It occurs when abnormal myeloid cells and monocytes grow and divide in the bone marrow.
The treatment for each type of leukemia in children may differ depending on the subtype, stage of the disease, and individual patient factors. Treatment options may include chemotherapy, radiation therapy, targeted therapy, stem cell transplant, or a combination of these approaches.
Causes and Risk Factors
The exact causes of leukemia in children are not known, but research suggests that a combination of genetic and environmental factors may play a role. Some of the known risk factors for leukemia in children include –
- Genetic factors – Some genetic syndromes, such as Down syndrome, Fanconi anemia, and Bloom syndrome, are associated with an increased risk of developing leukemia in children.
- Exposure to radiation – Children who have been exposed to high levels of radiation, such as those who have undergone radiation therapy for cancer treatment or those who have been exposed to nuclear fallout, have an increased risk of developing leukemia.
- Exposure to certain chemicals – Exposure to certain chemicals, such as benzene and pesticides, has been linked to an increased risk of developing leukemia in children.
- Viral infections – Some viral infections, such as human T-cell leukemia virus type 1 (HTLV-1) and Epstein-Barr virus (EBV), have been linked to an increased risk of developing leukemia in children.
- Weakened immune system – Children with weakened immune systems, such as those with HIV/AIDS or those who have undergone organ transplantation, have an increased risk of developing leukemia.
- Family history – Children who have a sibling or parent with leukemia have a slightly increased risk of developing the disease themselves.
It’s important to note that most children who develop leukemia do not have any known risk factors, and not all children with risk factors will develop the disease. However, knowing the risk factors can help parents and healthcare providers be more vigilant in monitoring the signs and symptoms of leukemia in children.
The symptoms of leukemia in children can be non-specific and can be similar to other childhood illnesses. However, it is important for parents and caregivers to be aware of the following symptoms that may indicate leukemia –
- Fatigue – Children with leukemia may feel extremely tired and weak even after getting enough sleep.
- Pale skin – Children with leukemia may appear pale or have a yellowish tint to their skin.
- Fever – Children with leukemia may have frequent and prolonged fevers that do not go away with medication.
- Easy bruising or bleeding – Children with leukemia may develop bruises or small red or purple spots on their skin, or may have bleeding gums or nosebleeds.
- Joint or bone pain – Children with leukemia may experience pain in their joints or bones, particularly in the legs.
- Swollen lymph nodes – Children with leukemia may have swollen lymph nodes in their neck, armpits, or groin.
- Abdominal pain – Children with leukemia may experience pain or discomfort in their abdomen.
- Loss of appetite – Children with leukemia may have a decreased appetite and may lose weight.
- Recurrent infections – Children with leukemia may have frequent infections such as colds, ear infections, or pneumonia.
These symptoms may be indicative of other conditions as well. If parents or caregivers notice any of these symptoms in a child, they should consult a healthcare provider for further evaluation and diagnosis.
Diagnosis and Tests
The diagnosis of leukemia in children typically involves several tests and procedures, including –
- Medical history and physical exam – The healthcare provider will ask about the child’s medical history and symptoms and perform a physical exam to check for signs of leukemia, such as swollen lymph nodes or an enlarged spleen or liver.
- Blood tests – Blood tests, including a complete blood count (CBC) and blood smear, are used to check the number and types of blood cells in the child’s body. Children with leukemia may have low levels of red blood cells, white blood cells, and platelets.
- Bone marrow aspiration and biopsy – This procedure involves taking a sample of bone marrow from the hip bone using a needle. The sample is then examined under a microscope to check for the presence of leukemia cells.
- Lumbar puncture – Also known as a spinal tap, this procedure involves inserting a needle into the child’s spinal column to collect a sample of cerebrospinal fluid (CSF), which surrounds the brain and spinal cord. The sample is then checked for the presence of leukemia cells. This test is important because leukemia cells can sometimes spread to the brain and spinal cord.
- Imaging tests – Imaging tests, such as X-rays, CT scans, or MRI scans, may be used to check for enlarged lymph nodes, an enlarged spleen or liver, or other signs of leukemia.
- Genetic testing – Genetic testing may be performed to check for specific genetic abnormalities or mutations that are associated with certain types of leukemia.
The results of these tests are used to confirm a diagnosis of leukemia and to determine the specific type and subtype of leukemia the child has. This information is important in developing an appropriate treatment plan for the child.
Treatment for leukemia in children depends on several factors, including the type and subtype of leukemia, the child’s age and overall health, and the extent of the disease. The main treatments for leukemia in children include –
- Chemotherapy – This is the main treatment for most types of childhood leukemia. Chemotherapy drugs are given either orally or through an intravenous (IV) line, and they work by killing leukemia cells. Chemotherapy is usually given in cycles, with periods of treatment followed by periods of rest.
- Radiation therapy – Radiation therapy may be used to treat leukemia that has spread to the brain or other parts of the body. It involves using high-energy radiation to kill cancer cells.
- Stem cell transplant – Stem cell transplant, also known as bone marrow transplant, may be used in children with high-risk or relapsed leukemia. It involves replacing the child’s bone marrow with healthy bone marrow from a donor.
- Targeted therapy – Targeted therapy is a newer type of treatment that uses drugs to target specific proteins or genetic abnormalities that are involved in the development of leukemia.
- Immunotherapy – Immunotherapy is a type of treatment that helps the immune system fight cancer. It involves using drugs to stimulate the immune system to attack leukemia cells.
The specific treatment plan for a child with leukemia will depend on several factors, including the type and subtype of leukemia, the child’s age and overall health, and the extent of the disease. The healthcare team will work with the child and family to develop a personalized treatment plan that is best for the child.
The outlook for leukemia in children depends on several factors, including the type and subtype of leukemia, the child’s age and overall health, and how quickly the leukemia is diagnosed and treated.
In general, the prognosis for childhood leukemia has improved dramatically in recent decades due to advances in treatment. Today, the overall survival rate for childhood leukemia is around 90%, meaning that about 9 out of 10 children with leukemia will survive.
However, the prognosis for individual children can vary widely depending on several factors. For example, children with certain subtypes of leukemia may have a better or worse prognosis than children with other subtypes. Children who are diagnosed at an early stage of the disease and respond well to treatment may have a better prognosis than children who are diagnosed at a later stage or who do not respond well to treatment.