What Is the Survival Rate for AML in Children?

Acute myeloid leukemia (AML) is bone marrow cancer. AML malignant cells are immature myeloid blood cells. Myeloid cells in AML somehow evade the normal controls that direct their maturation into normal blood cells. The cause of AML is unknown, but it is neither hereditary nor contagious. Environmental and genetic factors are currently being researched as potential factors.

As the leukemic blast cells multiply in the bone marrow, they crowd out the normal cells that grow there. They eventually take up so much space that red blood cells, platelets, and normal white blood cells can no longer be produced. When this occurs, a child develops symptoms indicating that normal blood cells are not being produced sufficiently.

In general, there are three main causes of this AML:

1. Exposure to radiation
2. Exposure to benzene
3. Combination of both

Risk factors for AML

• Gender (Men are more prone to this type of cancer.)
• Smoking, including passive smoking
• Exposure to radiation
• Exposure to chemotherapy drugs in combination with radiation therapy
• Having pre-existing blood disorders
• Exposure to cleaning drugs and detergents that contain benzene)
• Birth defects, such as Down’s syndrome
• Certain occupations (People who work in the nuclear industry are highly exposed to radiation, which increases their risk of AML.)

AML cannot be prevented in a way that is 100 percent effective; however, there are ways to reduce the risk, such as limiting one’s exposure to chemicals and radiation and avoiding smoking.

Most children and adolescents with AML show symptoms within a few weeks. These are caused by an increase of malignant cells in the bone marrow, as well as their spread to other organs and tissues. The unregulated development of leukemia cells in the bone marrow impairs normal blood cell synthesis and may lead to various symptoms.

Signs and symptoms of AML in children

• Most common symptoms (seen in 60 percent of patients)
  • Fatigue, exhaustion, weariness, malaise, and pallor: Caused by the lack of red blood cells or anemia.
  • Fever and/or frequent nonspecific infections: Due to the lack of white blood cells or neutropenia.
  • Abdominal pain and loss of appetite: Due to the enlargement of the spleen and/or liver.
• Common symptoms (seen in 20 to 60 percent of patients)
  • Increased risk of bleeding (nose bleeding, gum bleeding)
  • Excessive bruising
  • Pinpoint, round and red spots on the skin, also called petechiae
  • Cerebral hemorrhage due to lack of platelets
  • Enlarged lymph nodes in the neck, armpits, and groin
  • Bone and joint pain
• Rare symptoms (seen in 20 percent of patients)
  • Headache
  • Visual disturbances
  • Vomiting
  • Cranial nerve palsies 
  • Shortness of breath
  • Tumorlike local masses of leukemia cells in the skin, lymph nodes, bone, and, sometimes, around the eyes; partly bluish green
  • Gum enlargement 
  • Enlargement of testicles

The type and severity of AML symptoms differ from person to person. Many of the symptoms described above are also seen in common and relatively harmless childhood diseases. However, if these symptoms reoccur frequently or persistently, a doctor should be consulted as soon as possible. If acute leukemia is diagnosed, treatment must be initiated promptly.

If acute myeloid leukemia (AML) is suspected or diagnosed, treatment should begin as soon as possible. Depending on the child's signs and symptoms, doctors may chart an individualized treatment plan. Blood transfusions and symptomatic treatment options may be recommended along with the main treatment options.

Treatment options for AML in children

• Chemotherapy or polychemotherapy: Chemotherapy is the mainstay of AML treatment. It uses drugs that can either kill or inhibit the growth of rapidly dividing cancer cells.
  • As a single drug may not be capable of destroying all leukemia cells, a combination of drugs that work in different ways is usually administered (polychemotherapy).
• Radiation therapy of the brain: It is done in a few cases in addition to chemotherapy to treat patients with central nervous system involvement.
  • Patients who do not respond to treatment or develop recurrent disease may benefit from high-dose chemotherapy followed by stem cell transplantation.

The main goal of treatment is to eliminate as many leukemia cells as possible from the body so that the bone marrow can resume its function. Specific supportive care regimens have been established to prevent or adequately manage the side effects of intensive therapy, and they now represent an important and efficient component of AML treatment.

AML treatment for children and teenagers consists of several steps. These steps (or phases) serve various functions. As a result, they differ in terms of duration, treatment intensity, and drug combinations used.

Major treatment elements

• Induction therapy
  • Induction therapy consists of intensive chemotherapy with various anticancer agents (polychemotherapy). 
  • The goal is to achieve remission. 
  • Induction therapy generally lasts two months and consists of two courses of chemotherapy with a recovery period in between.
• Consolidation therapy
  • This comprises three cycles of intense chemotherapy but with drugs other than those used during induction. 
  • Consolidation therapy, which takes three to four months, is intended to further reduce the residual leukemia cells, thus lowering the patient's chance of having recurrent cancer.
• Central nervous system (CNS)-directed therapy
  • This treatment is recommended for all patients with AML. It is intended to prevent the spread of leukemia cells to the CNS or to prevent further spread if the CNS has already been affected. 
  • CNS treatment occurs during systemic therapy and includes administering anticancer drugs into the spinal canal via a lumbar puncture. Brain radiotherapy is recommended in addition to chemotherapy if the CNS is involved. 
  • Radiation takes about two to three weeks and is administered after consolidation therapy.
• Maintenance therapy
  • A milder form of polychemotherapy. It is mostly administered orally to children who are outpatients. 
  • Maintenance therapy aims to fight all leukemia cells that may have survived intensive treatment over a long period, usually about a year after intensive therapy is stopped.
• New therapeutic strategies: Because research in this field is very active, it is not surprising that new drugs for these diseases have been developed. The majority of them are still not part of established treatment protocols, but many are in the advanced stages of clinical use.
• New chemotherapeutic drugs: These work the same way as existing drugs, but they are more effective and/or less toxic. Some recently discovered chemo drugs allow for high doses of treatment to be administered, making them very effective besides being low in toxicity.
• Targeted therapies: These drugs target specific components of cancer cells but have little effect on healthy cells.
• Immunotherapy: Immunotherapy uses the body's immune system to combat leukemia cells. It has become one of the main research fields in recent years, but it currently has little application in AML.
• Clinical trials
  • A patient must consult a doctor if clinical trials are the only option. The treatment concepts of such trials are constantly optimized based on the current state of medical knowledge. 
  • Such trials are also known as "multicenter" or "multicentric" trials because they involve many treatment centers and frequently involve many countries. 
  • Patients are generally treated according to the trial center’s recommendations, ensuring they receive the most up-to-date treatment available.

The survival rate for children with AML has increased significantly in recent years, approaching 65 percent. This improvement can be attributed to increased chemotherapy intensity, better classification of patients into risk groups, the implementation of more effective support measures, such as better antibiotics, the ease with which blood and platelet transfusions can be obtained, diet assistance, and specialized nursing as well as a notable improvement in the selection of donors for stem cell transplantation.