People can develop therapy-related acute myeloid leukemia after undergoing certain cancer treatments, such as chemotherapy or radiation.

Acute myeloid leukemia (AML) is a blood or bone marrow cancer. It can spread quickly and requires prompt treatment.

In some cases, receiving chemotherapy or radiation treatment for another type of cancer may trigger the development of AML. Doctors classify this as therapy-related acute myeloid leukemia (t-AML), as it has developed as a side effect of certain medications used for cancer treatment.

Read on to learn more about t-AML, its symptoms, causes, diagnosis, treatment, and outlook.

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T-AML is a fast-growing form of AML. The most common cause of t-AML is undergoing chemotherapy or radiation therapy.

People with this condition have increased production of immature white blood cells. These cells are not completely developed and cannot fight infections. A person may also have decreased red blood cell and platelet counts.

T-AML accounts for about 7–8% of all cases of AML. It typically occurs within 7 years of chemotherapy or radiation therapy.

The overall 5-year survival rate for people with t-AML is about 10%.

However, the outlook can vary depending on various factors, including:

  • a person’s age
  • other underlying conditions
  • type of chromosomes in the cells, known as a karyotype

Older adults, or those with a less favorable karyotype, have an average overall survival of 6 months. People with a more favorable karyotype have an overall survival of about 27 months.

The signs and symptoms of t-AML can vary from person to person. Some symptoms may include:

  • bruising
  • discolored spots on the skin
  • discoloration of the skin due to low red blood cell count
  • fatigue
  • unusual and frequent bleeding
  • breathlessness
  • bone and joint pain
  • recurrent infections
  • night sweats and fever
  • swollen glands
  • abdominal discomfort
  • unexpected weight loss

Undergoing chemotherapy or radiation therapy for cancer may lead to the development of t-AML in the future.

Certain types of chemotherapy drugs are more likely to increase the risk of developing t-AML than others. The amount of time before the onset of t-AML may also vary depending on the past cancer treatment.

On rare occasions, t-AML may also occur in people who survived breast cancer.

A 2019 study reported that about 1.8% of people who received chemotherapy treatment for breast cancer developed t-AML within 10 years.

The diagnosis of t-AML typically starts with a blood test. Atypical white blood cell levels or a low blood count may indicate leukemia.

If doctors suspect leukemia, they may also prescribe additional tests, including:

  • Bone marrow biopsy: During this procedure, the healthcare team will collect a sample of bone marrow for testing. Examining the sample can help determine the type of leukemia a person may have.
  • Genetic test: This can help determine what type of leukemia a person with suspected AML may have. Knowing the type of leukemia a person has can help doctors recommend the best treatment.
  • Lumbar puncture: This exam helps determine whether cancer has spread to the nervous system.

The treatment for t-AML may vary from person to person. However, it usually consists of two phases:

  • Induction: This is the initial treatment and aims to achieve remission of leukemia by killing as many cancerous cells as possible and treating its symptoms. Induction treatment typically includes chemotherapy, but this may vary depending on the individual’s health.
  • Consolidation: This phase aims to prevent a comeback — or relapse — of cancer. The consolidation treatment may include a stem cell transplant from a donor, targeted therapy, and infusions of blood rich in white blood cells from the same person who might have donated stem cells for transplant. Doctors may recommend undergoing radiation therapy before undergoing a stem cell transplant.

People who experience any symptoms of leukemia should consider contacting a healthcare professional.

Experiencing symptoms of leukemia does not mean a person has it. However, as t-AML can develop and spread quickly, people who notice any symptoms should promptly contact a doctor.

People who have undergone cancer treatment, such as chemotherapy or radiation therapy, may have a higher risk of developing t-AML. The onset of this condition typically occurs within 7 years of starting cancer treatment, and it is more common in older adults.

Doctors typically treat t-AML with chemotherapy during the first stages of the treatment. They may also recommend undergoing radiation therapy, a stem cell transplant, and targeted therapy.