Doctors recommend chemotherapy to treat acute myeloid leukemia (AML). The nature and duration of chemotherapy treatment will vary depending on the type of AML a person has, but most people who receive chemotherapy for AML do go into remission.
AML chemotherapy usually starts with 1 week of intense treatment. After this, the person may receive a 5-day treatment session every 4 weeks, with the cycle repeating three or four times.
Doctors usually recommend a combination of chemotherapy medications rather than a single one.
This article looks at the phases, duration, and side effects of chemotherapy for AML, as well as the outlook.
According to the American Cancer Society (ACS), chemotherapy is the main treatment option for people with AML. AML is a type of cancer that affects the bone marrow and blood.
Chemotherapy either kills cancer cells or stops them from dividing.
Doctors may prescribe systemic or regional chemotherapy, according to the National Cancer Institute (NCI).
With systemic chemotherapy, the bloodstream circulates the drugs throughout the body. Types of systemic chemotherapy include:
- oral, wherein a person takes medications by mouth
- intravenous, wherein a doctor injects medications into a person’s vein
- intramuscular, wherein a doctor injects medications into a person’s muscle
Regional chemotherapy affects a limited area of the body. It may involve intrathecal administration, wherein a doctor injects medications into a person’s cerebrospinal fluid. This is the liquid surrounding the spinal cord.
Regional chemotherapy may also involve a doctor injecting medications into an organ or body cavity, such as the abdomen.
Although doctors may sometimes prescribe a single chemotherapy drug, they often recommend a combination of such drugs, according to the NCI. Combinations of drugs tend to be more effective because they kill cancer cells in different ways.
The ACS states that doctors often use a combination of an anthracycline and cytarabine (Cytosar-U) to treat AML.
Anthracyclines are drugs that suppress the production of DNA and RNA, which provide the cells’ genetic code. Examples of these medications include daunorubicin (Cerubidine) and idarubicin (Idamycin).
Cytosar-U, on the other hand, is a drug that slows the growth of cancer cells. Doctors sometimes called this medication ara-C or arabinosylcytosine.
Chemotherapy for AML involves three phases, according to the ACS. These are the induction, consolidation, and maintenance phases. Doctors typically reserve the maintenance phase for one specific type of AML.
This is the first phase of treatment. It is short and intense, and the aim is to rid the blood and the bone marrow of leukemia cells.
Doctors advise this phase of chemotherapy after a person has recovered from the induction phase. The aim of the consolidation phase is to kill the small number of leukemia cells left behind.
An individual receives these medications in cycles, which means that there are rest periods between treatment phases.
This third phase involves receiving a low dose of a chemotherapy drug for months or years after the end of the consolidation phase.
Doctors only tend to use this to treat acute promyelocytic leukemia (APL).
The ACS states that certain chemotherapy durations are typical for a person with AML.
For example, the induction phase for AML treatment usually lasts for 7 days. People receiving this treatment usually need to stay in the hospital throughout the week and for some time afterward.
The consolidation phase may involve receiving high doses of a medication for 5 days. Individuals typically receive this every 4 weeks, usually three or four times.
Because chemotherapy affects healthy cells as well as cancer cells, it may lead to side effects.
These side effects differ with the type and dose of medication a person is receiving. They may include:
Doctors often have ways of treating a person’s side effects. For example, they may prescribe an anti-nausea medication to prevent vomiting.
Chemotherapy may also reduce blood cell counts, which may result in the following:
- tiredness and shortness of breath from having too few red blood cells
- a higher risk of infections from having too few white blood cells
- easy bleeding or bruising from having too few platelets, which are the blood components that enable normal clot formation
Most side effects subside once a person’s treatment ends, but low blood cell counts might last for several weeks.
Having a low white blood cell count produces some of the most serious side effects because it increases the risk of infections. To prevent this, doctors may prescribe an antibiotic at the first sign of an infection from bacteria.
Low red blood cell and platelet counts may also linger. When these occur, doctors may recommend transfusions.
If a person has a large number of leukemia cells in the body, they may experience a side effect called tumor lysis syndrome. This usually happens in the induction phase of treatment.
When chemotherapy kills leukemia cells, the cells break open and spill their contents into the bloodstream. Consuming more fluids during treatment can help prevent or reduce this effect.
The ACS points out that 2 out of 3 people who undergo induction chemotherapy experience complete remission.
A person is in remission if all three of the following conditions apply:
- Their bone marrow has under 5% blast cells, which are very early forms of blood-making cells that are not normally present in the blood.
- Their blood cell count is within normal limits.
- They have no signs or symptoms of the cancer.
People who go into remission after the induction phase typically move on to the consolidation phase of treatment, where they receive further chemotherapy.
Up to 50% of people who undergo consolidation chemotherapy go into long-term remission.
APL is an aggressive form of AML.
With this condition, many immature blood-forming cells, called promyelocytes, build up in the bone marrow and blood. This accumulation leads to decreased numbers of red blood cells, white blood cells, and platelets.
Treatment for most people with APL involves a combination of an anthracycline and all-trans-retinoic acid, which is a medication related to vitamin A.
The ACS provides treatment outcome statistics for individuals with APL. For example, it says that 9 out of 10 people who have this condition go into remission with induction chemotherapy.
It also says that after consolidation and maintenance chemotherapy, 8 or 9 out of 10 people stay in long-term remission.
AML chemotherapy may cause an array of side effects.
A combination of medications, such as anti-nausea drugs, and procedures, such as blood transfusions, may help.
A person with the type of AML called APL has an aggressive form of the cancer. However, if they receive chemotherapy, they have a high likelihood of going into long-term remission.