Leukemia -Acute Myeloid Leukemia (AML) - Adults

Acute Myeloid Leukemia (AML) - Adults

Acute Myeloid Leukemia (AML) is a type of blood cancer where healthy blood cells begin to divide uncontrollably. It starts in the bone marrow, the spongy tissue within bones, and affects myeloblast cells, which normally mature into white blood cells (WBCs), red blood cells (RBCs), or platelets. AML is also known as acute myelogenous leukemia, acute myelocytic leukemia, or acute non-lymphocytic leukemia. Since AML progresses rapidly, immediate treatment is necessary.

Bone Marrow and AML Development

Bone marrow is responsible for producing three major types of blood cells:

• White Blood Cells (WBCs): Fight infections.

• Red Blood Cells (RBCs): Carry oxygen throughout the body.

• Platelets: Help in clotting blood to prevent bleeding.

AML occurs when genetic mutations in myeloblasts cause these cells to grow and divide abnormally, leading to the overproduction of immature myeloid cells. This excess inhibits the formation of healthy blood cells, causing the following symptoms:

• Fatigue: Due to low RBC levels.

• Infections: Caused by a decrease in WBC count.

• Bleeding and bruising: Resulting from reduced platelets.

AML primarily affects the bone marrow but can spread to other organs, such as lymph nodes, the liver, spleen, and brain.

Statistics

• In India, approximately 48,419 leukemia cases are reported annually, though specific data for AML are not available.

• In the United States, about 20,380 cases of AML are diagnosed every year.

Survival Rates

• Adults over 20 years old: 5-year survival rate is approximately 28%.

• Under 20 years old: The survival rate increases to 69%.

Risk Factors

• Age: Most cases are diagnosed in people over 65 years.

• Smoking: Increases AML risk.

• Genetic disorders: Conditions like Down syndrome, Li-Fraumeni syndrome, and Klinefelter syndrome.

• Radiation exposure: High levels increase the chance of developing AML.

• Previous chemotherapy: Increases the risk of secondary AML.

• Chemical exposure: Contact with substances like benzene.

• Bone marrow disorders: Conditions like myelodysplastic syndrome and aplastic anemia.

Symptoms

Common symptoms include:

• Persistent fatigue

• Weakness

• Easy bruising or bleeding

• Pale skin

• Red spots under the skin

• Unexplained weight loss

• Fever

• Bone or joint pain

• Swollen lymph nodes

• Breathlessness

• Headaches

• Blurred vision

• Frequent infections

• Chest pain

• Heavy or prolonged menstrual periods

Diagnosis

1. Complete Blood Count (CBC): Identifies abnormalities in WBC, RBC, or platelet levels.

2. Bone Marrow Aspiration and Biopsy: Confirms AML by extracting bone marrow samples for analysis.

3. Flow Cytometry: Identifies specific markers on leukemia cells.

4. Cytogenetics or Karyotyping: Detects chromosomal abnormalities using techniques like FISH.

5. Molecular Testing: Identifies genetic mutations for targeted therapies.

6. Lumbar Puncture (Spinal Tap): Checks for leukemia cells in the cerebrospinal fluid.

7. Imaging Tests: CT scans, MRI, and PET-CT help assess the spread of the disease.

Treatment

1. Intensive Chemotherapy:

Chemotherapy aims to kill cancer cells and consists of three phases:

• Induction Therapy: The first phase to achieve complete remission (CR) by eliminating visible leukemia cells.

• Consolidation Therapy: Aims to destroy any remaining cancer cells.

• Maintenance Therapy: Administers low-dose chemotherapy over 2-3 years to prevent relapse.

2. Stem Cell/Bone Marrow Transplantation:

• Allogeneic Transplant (ALLO): Uses stem cells from a donor.

• Autologous Transplant (AUTO): Rarely used in AML, as it involves using the patient’s own stem cells.

This therapy is essential for patients at high risk of relapse.

3. Targeted Therapy:

AML cells with specific genetic mutations can be treated with targeted therapies:

• FLT3 Mutations: Midostaurin (Rydapt), Gilteritinib (Xospata).

• IDH1/IDH2 Mutations: Enasidenib (IDHIFA), Ivosidenib (Tibsovo).

• Acute Promyelocytic Leukemia (APL): A subtype treated with all-trans retinoic acid (ATRA) and arsenic trioxide.

4. Radiation Therapy:

• Used to treat AML cells in the brain or spinal cord.

• Delivered through external beam radiation therapy.

Side Effects of Treatment

• Chemotherapy: Hair loss, nausea, vomiting, fatigue, infections, and low blood counts (anemia, low platelets, low WBCs).

• Radiation Therapy: Skin irritation, fatigue, and hair loss at the treatment site.

• Stem Cell Transplantation: Risks include infections, bleeding, and graft-versus-host disease (GVHD) if donor cells attack the patient’s tissues.

Follow-Care

After AML treatment, regular follow-up is essential to monitor for:

• Relapse: Routine blood tests and imaging scans help detect any recurrence.

• Managing side effects: Ongoing care to address long-term side effects, such as fatigue or infertility.

• Psychological support: Counseling may be needed to help patients cope with the emotional impact of AML treatment.

AML is a fast-progressing cancer that requires immediate medical intervention. Early detection and treatment can significantly improve survival rates, especially in younger patients. Continuous monitoring and personalized care ensure better outcomes for those undergoing treatment for AML.

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