Acute myelomonocytic leukemia (AMML) is a form of acute myeloid leukemia that involves a proliferation of CFU-GM myeloblasts and monoblasts. AMML occurs with a rapid increase amount in white blood cell count and is defined by more than 20% of myeloblast in the bone marrow. It is classified under "M4" in the French-American-British classification (FAB). It is classified under "AML, not otherwise classified" in the WHO classification.Translocations have been observed. Progression from myelodysplastic syndrome has been reported. Signs and symptoms
Some patients may experience:
Fatigue
Easy Bruising
Abnormal Bleeding
Anemia
Thrombocytopenia
DyspneaIf the blast count gets too high and clog up blood vessels, some patients may experience:
Slurred Speech
Headache
Confusion
Weakness on one side of the body
Sleepiness

Cause
The cause has not yet been determined. It has been said that acute myeloid leukemia can occur from a progression of chronic myelomonocytic leukemia type 1 and 2. Normal red blood cells decrease and a rapid proliferation of the abnormal myeloblasts occur. Apoptosis functional ability decreases which causes a back up of myeloblasts in the bone marrow and blood. AML with a translocation or inversion is seen in different chromosomes. Specifically, AML with inversion in chromosome 16 also known as inv(16) is commonly seen in children. Mechanism
AMML does not have an exact mechanism. The underlying pathophysiology of acute myeloid leukemia consist of maturational arrest of the bone marrow cell during the early stages of development. A myeloblast is an immature precursor cell that will change into a monocyte, healthy white blood cell. In AML, Myeloblast do not mature but grow and multiply with regulation.
Chemotherapy is broken down into 2 phases:

Induction therapy: first short and invasive phase of treatment with the goal to the blood of blasts and reduce the number of blasts in the bone marrow back to normal. Consolidation therapy: second phase given in cycles that occur after the patient has recovered from induction therapy. Its objective is to kill remaining blasts that cant be seen.In some cases, an allogenic bone marrow transplantation can be performed. If AML with chromosomal abnormalities such as inv(16) are often cured by the standard chemotherapy regimen. Prognosis
With AMML being difficult to fully treat, the five-year survival rate is about 38-72% which typically decrease to 35-60% if theres no bone marrow transplantation performed. Generally older patients over 60 have a poor outlook due to prior health status before the diagnosis and the aggressive chemotherapy regimen used. The aggressive chemotherapy regimen can lead to long-term side effects such as prolonged anemia, leukocytopenia, neutropenia, and thrombocytopenia. The use of anthracycline drugs can cause a decrease in cardiac contractility, both short and long term. Those with AML-M4 inv(16) have a favorable prognosis with a five-year overall survival rate of 61%. Epidemiology
AML is commonly seen in pediatric patients with higher pediatric incidence in Hispanics and Asians as compared to non-Hispanic Caucasian and African Americans in the USA. Predisposition to AML includes but not limited to:Down syndrome, Klinefelters syndrome, and Fanconis anemia. Acquired predisposing factors include: aplastic anemia, chemotherapy, prenatal exposure to tobacco, marihuana, and alcohol.