Cancer is when cells in the body change and grow out of control. Your body is made up of tiny building blocks called cells. Normal cells grow when your body needs them, and die when your body does not need them any longer. Cancer is made up of abnormal cells that grow even though your body doesn’t need them. In most types of cancer, the abnormal cells grow to form a lump or mass called a tumor.
Leukemia is different from most other types of cancer. Leukemia is cancer that starts in the bone marrow, which is where new blood cells are made. The bone marrow is a thick, sponge-like tissue in the center of certain bones.
Leukemia cells are early or immature forms of blood cells, most often white blood cells. When a person has leukemia, the body makes too many abnormal blood cells. These cells don't work the way they should and don't mature into functional cells. Leukemia cells do not usually form tumors, but they can travel with the blood all over the body. That means leukemia can affect organs all over the body.
Two types of white blood cells can turn into leukemia:
Lymphoid cells (lymphocytes). This is called lymphocytic or lymphoblastic leukemia.
Myeloid cells (myelocytes). This is called myeloid or myelogenous leukemia.
Leukemia can also be either acute or chronic. Acute leukemia tends to grow very quickly and needs to be treated right away. Chronic leukemia often grows more slowly.
Acute myeloid leukemia (AML) is a type of leukemia that starts in very early or immature forms of white blood cells called myeloblasts (or blasts for short). It’s also known as acute myelogenous leukemia. In some cases, the leukemia cells can be early red blood cells called megakaryocytes.
As the leukemia cells grow, they crowd out the normal cells in the bone marrow. This can lead to not enough of different types of healthy blood cells. People with AML have too many white blood cells in their blood. But these cells are not normal and don't help fight infections. In fact, people with AML often get more infections than people without it. AML can also lead to not enough red blood cells. This condition is called anemia, and it can cause fatigue. AML can lead to not enough platelets, too. This can lead to excess bleeding or bruising.
AML is a type of acute leukemia. This means it tends to grow fast. It needs to be treated right away.
AML comes in many subtypes. They are based on what type of cells the leukemia starts in and how mature the cells are. Which subtype of AML you have can affect both your treatment and prognosis (outlook). The main classification system of subtypes includes:
M0. This is undifferentiated AML.
M1. This is AML with minimal maturation.
M2. This is AML with maturation.
M3. This is acute promyelocytic leukemia (APL).
M4. This is acute myelomonocytic leukemia (AMML).
M4eo. This is AMML with eosinophilia.
M5. This is acute monocytic leukemia.
M6. This is acute erythroid leukemia.
M7. This is acute megakaryoblastic leukemia.
AML may be broken down into other subtypes with a different system than this one. Ask your healthcare provider which system he or she is using and what it means for you. The subtype of AML may determine which treatment is most appropriate.
Another aspect of typing that's done for AML is looking for certain genetic changes in the leukemia cells. These changes can help your healthcare provider decide on the best treatment plan.
If you have questions about your AML, talk with your healthcare provider. Your healthcare provider can help you understand more about this type of leukemia.