Acute myeloid leukemia (AML) goes by many names: acute nonlymphocytic leukemia, acute myelocytic leukemia, acute granulocytic leukemia, acute myelogenous leukemia. “Acute” (as opposed to chronic) signifies that it is an aggressive form of blood cancer, in which the leukemic cells rapidly multiply. Left untreated, AML can be life-threatening. That said, with treatment — of which there are many options — AML’s prognosis is improving. “There's a lot of hope,” said Dr. Naveen Pemmaraju, an expert in multiple areas of acute and chronic leukemia.
Dr. Naveen Pemmaraju is an associate professor of leukemia at MD Anderson Cancer Center in Houston. He also treats people with leukemia in the clinic and is a clinical trials specialist. Dr. Pemmaraju found time in his busy schedule to sit down with MyLeukemiaTeam to talk about the most recent developments in the AML research space.
AML is a type of leukemia. Leukemia is a blood cancer that starts in the bone marrow, where blood cells are produced. AML begins in blood stem cells as they’re forming in a person’s bone marrow. AML cells, also called blast cells, crowd out normal blood stem cells and cause a shortage of healthy cells. It is possible for AML to spread to the spleen, liver, and testicles. AML can sometimes also spread to the brain and spinal cord, collectively known as the central nervous system.
There will be around 20,000 AML diagnoses in the United States in 2020. While an AML diagnosis can occur at any age, AML more commonly affects older or middle-aged adults. It impacts men slightly more frequently than women. The average age of an initial AML-diagnosis is around 68 years old. While far less common, AML does occur in children, adolescents, and younger adults.
AML has several subtypes. The subtype of AML is an important factor in determining the best treatment. For example, acute promyelocytic leukemia (APL) is an AML subtype that requires treatment using nonchemotherapy drugs that aren’t usually used with other subtypes of AML. The subtype of AML can also be a strong indicator of one’s disease prognosis or how successful a treatment will be.
In recent years, cancer research has yielded breakthroughs in the discovery of certain molecular subtypes of AML. Two main systems are used to define the subtype of AML: the French-American-British (FAB) and World Health Organization (WHO) classification systems.
AML subtypes are classified by the following factors:
Learn more about the stages and subtypes of AML.
AML is caused by specific genetic changes, or mutations, including chromosomal duplications, deletions, and inversions. In some AML cases, the leukemic cells have mutations on the FLT3 gene. Mutations on IDH1 or IDH2 affect other people with AML. Changes to CD33 genes to the “hedgehog pathway” or BCL-2 protein are also factors.
Most DNA mutations linked to AML are acquired. This means the mutations occur during a person’s life and are not inherited from their family. These mutations appear to happen as a person gets older, which may explain why AML occurs more frequently in older adults.
“There are not many known or controllable risk factors for the disease,” explained Dr. Pemmaraju. “There are some families with hereditary or genetic features, and we follow a lot of those families in our leukemia genetics clinic.”
Some people are at increased risk of developing acute granulocytic leukemia due to having other blood disorders, for instance myelodysplastic syndromes, or inherited disorders such as Down syndrome. Having previously undergone chemotherapy or radiation therapy may also increase a person’s risk for AML.
“Certain genetic factors that have really only been discovered in the last five to seven years may also increase your AML risk,” Dr. Pemmaraju said. “Ask your doctor about chromosomal karyotype and cytogenetic analysis and molecular testing if you have concerns.”
Read more about causes of AML.
Many symptoms of AML are related to a deficiency of normal blood cells. People with AML may also have symptoms such as headache, fatigue, and weight loss, which are similar to other types of leukemia.
Red blood cells’ job is to carry oxygen around the body. Low red blood cell counts, also known as anemia, can cause the following symptoms:
White blood cells are a vital part of the immune system and help fight off disease and infections. Low white blood cell counts, also called leukopenia, can lead to recurring or long-lasting infections which may involve fevers. Having an insufficient number of neutrophils, white blood cells that fight infection, is called neutropenia. Symptoms of a low white blood cell count include:
Platelets are cell fragments needed for normal blood clotting. Insufficient levels of platelets, known as thrombocytopenia, can cause symptoms such as:
Read more about signs and symptoms of AML.
Unfortunately, there are no early screening exams or diagnostic tests for AML. To diagnose AML and determine its subtype, several tests may be done. First, your doctor will take a detailed medical history and conduct a physical exam. The primary diagnostic tests for AML include:
Read more about tests for diagnosing AML.
Once you've been diagnosed with AML, your cancer care team will discuss your treatment options with you. Usually, your team will include a hematologist-oncologist — a doctor who specializes in blood disorders and cancer. Other health care professionals may be consulted or added to the treatment team to provide supportive care.
The goal of AML treatment is generally to achieve complete remission. But treatment options depend on specific factors relating to the cancer itself and the person living with AML, including age and overall health. Notably, cases of pediatric AML also require different treatment from adult AML cases. Treatment may also depend on whether it's an initial AML diagnosis or a recurrence of leukemia. Treatment needs to start as soon after diagnosis as possible because AML is an aggressive and rapidly progressing form of leukemia.
Depending on your treatment plan, treatment for AML can last for several months. You will likely be asked to follow up for monitoring tests every few months for several years after treatment is completed.
It’s important to note that most, if not all, cancer treatments present some level of risk and may cause side effects. You should discuss both potential risks and any side effects you’re having with your doctors to ensure the best possible outcome and maximize your quality of life.
“It's your body, it's your life,” said Dr. Pemmaraju. The American Cancer Society has a list of questions you may want to ask your AML treatment providers when considering your options.
Contrary to popular belief, clinical trials aren’t a last-line option after all other treatments have been tried. According to Dr. Pemmaraju, “Clinical trials are the number one recommendation for any patient with leukemia. For AML there are several ongoing trials for front-line therapies with new drugs, old drugs in combination with new drugs, and older drugs but with new parameters.”
Chemotherapy (chemo) is the standard treatment for most people diagnosed with AML. Chemotherapy for AML is typically divided into two phases: remission induction and consolidation. These phases can be followed by maintenance therapy.
In contrast to chemotherapy, targeted therapy targets specific parts of AML cells. Targeted therapy can be effective if AML cells have certain gene changes or genetic mutations. “There have been multiple new approvals for targeted therapies for AML in particular,” explained Dr. Pemmarju. “In just the last two years, seven or eight oral targeted therapy drugs have been approved by the FDA.”
A stem cell transplant — sometimes called a bone marrow transplant — or surgery may also be included in an AML treatment plan. Each person’s treatment plan will depend on the specifics of the situation, the AML subtype, comorbidities, and any other health concerns.
Read more about treatments for AML.
Traditional chemotherapy drugs used to treat AML can cause bleeding and clotting problems for people with APL. For that reason, APL is usually treated with nonchemotherapy drugs, such as all-trans-retinoic acid and arsenic trioxide.
AML treatment response rates and prognosis vary depending on the age of the person, the subtype of AML, the specifics of the genetic mutations involved, and several other risk factors. “When we're talking about outcomes and prognosis, age is a huge factor, but not the only one,” said Dr. Pemmaraju. “We also have chromosomes and molecular features that identify high-risk leukemias — those are patients who are expected to maybe not do as well as their peers, and they may have a different treatment paradigm.”
Read more about AML survival rate and outlook.
No matter where you are on your leukemia treatment path, MyLeukemiaTeam is a community of people who know what you’re going through. Over 1,000 members have been diagnosed with acute myeloid leukemia. Members welcome newcomers, support each other, and are always ready to share their experiences.
What AML symptoms did you first experience? How has your treatment path unfolded? Leave a comment below or start a conversation on MyLeukemiaTeam.