Acute myeloid leukemia (AML) is a type of blood cancer that makes up about 80% of leukemias in adults. Secondary AML (sAML) is when AML evolves from a pre-existing blood condition.

Leukemia is a group of cancers that form in tissues that create blood cells. It’s classified based on the type of cells it develops in and how quickly it’s expected to spread. “Acute” means that AML tends to progress rapidly and “myeloid” means it develops in myeloid cells that become red blood cells, platelets, and some white blood cells.

Primary and secondary AML have different outlooks, which is related to a pre-existing condition.

What causes sAML, how it is diagnosed, and how it is treated are some of the things you can learn from this.

The term sAML is now used to refer to AML or myelodysplastic syndrome (MDS) that develops from a pre-existing blood condition. In the past, it was also used to refer to AML that developed after chemotherapy or radiation therapy, but this is now referred to as therapy-related AML (tAML).

Myelodysplastic syndrome (MDS) is a group of cancers in which blood cells in your bone marrow don’t become mature cells. About 1 in 3 cases of MDS progress to AML. Previously, it was called pre-leukemia or smoldering leukemia. It’s now considered a form of cancer.

When AML doesn’t occur after cancer therapy or in the presence of a blood condition, it’s known as primary or de novo (Latin for “of new”) AML. sAML occurs most often in adults over 65 years.

Studies estimate that sAML may make up 10% to 30% of cases of AML or MDS.

In a 2017 study, researchers defined sAML based on if a person had a prior diagnosis of myelodysplastic syndrome, myeloproliferative neoplasm, or aplastic anemia.

  • Myeloproliferative neoplasm is a group of rare blood cancers where bone marrow makes too many blood cells.
  • Aplastic anemia is a disease that causes the production of blood cells to be insufficient.

Symptoms of secondary AML tend to be similar to primary AML, but white blood cell count tends to be low in AML associated with MDS compared with high in primary AML.

General symptoms may include:

There are symptoms that can be developed from a low blood cell count. They can include:

Low red blood cell symptoms Low white blood cell symptoms Low platelet symptoms
fatigue frequent infections excessive bleeding
weakness lingering infections frequent bruising
shortness of breath There is a high degree of fever. frequent or severe nosebleeds
paleness increased menstrual bleeding
headaches bleeding gums
dizziness
feeling cold

The cause ofAML is thought to be genetic.

Stem cells that become blood cells divide about once every 40 weeks and develop about 11 mutations each time they divide. If these mutations occur in a gene linked to leukemia, it can lead to a condition called clonal hematopoiesis.

Clonal hematopoiesis is when a blood stem cell with certain mutations produces cells with the same genetic mutation. The presence of clonal hematopoiesis seems to increase the risk of developing blood cancer by 0.5% to 1% per year.

Some gene mutations are highly specific for sAML. These mutations include: SRSF2, SF3B1, and U2AF1.

Risk factors for AML

Risk factors for AML are known to include:

  • Increased age.
  • Being male.
  • smoking
  • Long-term exposure to benzene.
  • Exposure to radiation or drugs for tAML.
  • There are certain blood disorders for sAML.
  • certain genetic syndromes, such as Down syndrome
  • Family history.

Diagnosing sAML requires a biopsy of your bone marrow. If your doctor knows that you have a history of a previous blood disorder, radiation therapy, or chemotherapy, they may be able to make an sAML or tAML diagnosis if they see signs of AML in your biopsy sample.

The presence of genetic abnormality in your sample can be used to make a diagnosis.

A low blood cell count can be shown by a blood test.

Researchers are continuing to examine new treatment options for secondaryAML, which is harder to treat than primaryAML.

Chemotherapy

The drug Vyxeos (daunorubicin and cytarabine liposome for injection) was FDA approved for sAML in 2017. It’s typically given in 90-minute transfusions through an IV three times per day every second day.

In a 2018 phase 3 clinical trial, researchers found that Vyxeos led to complete remission in 47.7% of people versus 33.3% in people who received the drugs daunorubicin and cytarabine separately.

Vyxeos can cause severely low blood counts. It can take platelet levels 1 to 2 weeks longer to recover than with traditional chemotherapy.

Hypomethylating agents are drugs that are sometimes recommended by doctors for people who may benefit from less intensive therapy.

Stem cell transplants

Chemotherapy is often combined with a stem cell transplant. After receiving a very high dose of chemotherapy, you’ll receive a replacement of your bone marrow to replace the blood-forming cells that were killed.

Stem cell transplant can increase the amount of cancer treatment you can handle.

Stem cell transplants are generally only an option for people under the age of 60 to 65. But some researchers suggest that some people over 70 years who are in good health should be considered.

Targeted therapy

Mutations in the genes IDH1 and IDH2 are seen in about 5% and 20% of people with sAML, respectively. Targeted drugs called ivosidenib and enasidenib may help treat people with these mutations, but these drugs take several months to reach their maximum effect.

The outlook for people with sAML is generally worse than for people with primary AML. However, people with sAML tend to be older and frailer, which may contribute to a poorer outlook.

Survival is estimated to be 6 to 12 months even with intensive chemotherapy. AML developing from MDS seems to have a better outlook than AML developing from a non-MDS blood condition.

Risk factors associated with a worse outlook include:

  • There are certain genetic anomalies or defects.
  • Increasing age.
  • Performance status is not able to undergo daily activities.
  • Multidrug resistance can be resistance to drugs.
  • coexisting health conditions

When a previous blood condition develops into secondary AML, it is called secondary. It has a worse outlook than primary.

Researchers are looking at new treatments. Discuss treatment options with your doctor if you or your loved one is diagnosed with sAML. They can give you an idea of what to expect from treatment.

“If first-line therapy doesn’t work, your doctor can recommend alternative options, and let you know about clinical trials you may be eligible for.”