Acute myeloid leukemia (AML)

AML (also called acute myelogenous leukemia, acute nonlymphocytic leukemia, or
ANLL) is cancer of the blood cells. The cancer cells are those that would otherwise
develop into granulocytes and monocytes. Because treatments for AML and ALL are
very different, it is crucial that sophisticated laboratory studies are performed on the
bone marrow samples to determine whether your child has AML or ALL.
Eight thousand cases of AML are diagnosed in the US each year, most often in adults
over 50. Approximately 500 children are diagnosed with AML in the US every year,
with almost equal numbers of boys and girls. AML accounts for approximately 20
percent of all cases of childhood leukemia.
There are eight different subtypes of AML (M0 to M7) based on appearance of the
diseased cells under the microscope and certain genetic characteristics.
• M0: acute undifferentiated leukemia (less than 3 percent)
• M1: acute myeloblastic leukemia without maturation (20 percent)
• M2: acute myeloblastic leukemia with maturation (30 percent)
• M3: acute promyelocytic leukemia (AProL or APL with 15;17 translocation)
(5 to 10 percent)
• M4: acute myelomonocytic leukemia (AMML) (25 to 30 percent)
• M5: acute monocytic leukemia (AMoL) (15 to 20 percent)
• M5a: AMoL without differentiation (monoblastic)
• M5b: AMoL with differentiation
• M6: erythroleukemia (less than 5 percent)
• M7: acute megakaryocytic leukemia (5 to 10 percent)
My 6-year-old daughter had been getting bad headaches. The school
would call me to pick her up, and she would throw up all the way home.
She had an appointment with the optometrist who noticed an odd-looking
vein in her eye and that she looked pale and had some bruising. He
recommended taking her in for blood work. We did, and she was
diagnosed with AML type M2.
Approximately 80 percent of children less than 2 years old with AML have M4 or M5
subtypes. M7 leukemia is the most frequent form of AML in children with Down’s
syndrome who are less than 3 years old at the time of diagnosis.
Prognosis for the child with AML
Treatment for AML has dramatically improved in the last decade. Today, 75 to 85
percent of children who receive optimal treatment at a major pediatric medical center
achieve a complete remission. Of the children who achieve remission, 40 to 50
percent remain in remission for five years, and are considered cured.
The white blood count at diagnosis is the most important predictor of response to
treatment. Children with white blood counts over 100,000 per cubic milliliter at
diagnosis do not do as well as children with lower white counts. Other factors that
might predict more difficulty reaching remission are:
• Secondary AML (develops after treatment for another cancer)
• Monosomy 7 chromosome abnormality
• M4 and M5 subtypes
• Children with CNS disease at diagnosis
Factors that predict a high likelihood of achieving remission are:
• Rapid response to treatment
• Leukemia cell chromosomal abnormalities t(8;21) and inv (16)
• Down syndrome
Treatment for AML
Treatment for AML lasts for six to twelve months and is very intense. Acute compli-
cations of treatment are common. Children with this disease need to be treated at a
major pediatric hospital with expertise in treating acute leukemias. The goal of treat-
ment is to achieve a complete remission by obliterating all cancer cells as quickly as
possible and to prevent the disease from returning. Complete remission occurs when
all signs and symptoms of leukemia disappear; blood counts are rising towards
normal; and abnormal cells are no longer found in the blood, bone marrow (less than
5 percent blasts), and cerebrospinal fluid.
Chemotherapy is the primary treatment to induce remission in children with AML.
Radiation of the brain and sometimes the spinal cord is used infrequently. Stem cell