Leukemia Types and Their Characteristicsby Amy Hendel, P.A. Health Writer
The type of leukemia you’re diagnosed with will guide your treatment and affect your prognosis. There are four main types, based on whether your leukemia is acute or chronic, myeloid (also known as myelogenous) or lymphocytic (also known as lymphoblastic). They are: acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL). What differentiates these leukemias is how fast they grow and where they develop in your body.
Acute versus chronic leukemia
When mutated or cancerous blood cells overwhelm the numbers of normal blood cells, they can interfere with your body’s ability to control bleeding, fight infection, and deliver oxygen to normal cells. Acute leukemia cells multiply before any immune function has developed, while chronic leukemia cells have immature, limited immune function. Acute leukemia is fast-growing and can progress quickly without treatment, whereas chronic leukemia is slow-growing.
Symptoms of acute leukemia
Acute leukemia may mimic symptoms of the flu or other virus, and compel you to seek medical treatment. Other symptoms may include infections, tiny dots noticeable under your skin, cuts that don’t heal well, easy bruising, mild unexplained fevers, pale skin, night sweats, shortness of breath, and persistent fatigue.
Symptoms of chronic leukemia
Since chronic leukemias develop slowly, your symptoms may be mild typical complaints, such as bruising or swollen glands, or be attributable to other medical conditions. Chronic leukemias are often diagnosed during a routine blood test. Symptoms can include tiredness, bone or joint pain, weight loss, lack of appetite, night sweats, more frequent infections, bruising or sudden nosebleeds, enlarged lymph nodes, and pain or fullness in your upper abdomen, where the spleen is located.
Acute myeloid leukemia (AML)
AML comprises 32 percent of all adult leukemia cases, and is the second most common type of leukemia in children. It starts in your bone marrow where new blood cells are made, but quickly moves into your blood. It can then spread to other parts of your body, including your lymph nodes, liver, spleen, central nervous system (CNS), brain, spinal cord, and testicles. AML typically arises from cells that would be turning into white blood cells, but it can also develop from other blood-forming cells. AML may also be called acute granulocytic leukemia or acute non-lymphocytic leukemia.
Chronic myeloid leukemia (CML)
About 10 percent of leukemia cases are CML, mostly in adults, with half of the cases in people over 65. Like AML, it starts in blood-forming cells of the bone marrow and then travels into your blood system. CML specifically occurs in the early or immature versions of myeloid cells, which make red blood cells, platelets, and most of types of white blood cells. After mutated cells multiply, they spill over into your blood and can then travel to other organs. CML mostly occurs in adults, but can occur in children. It’s a slow-growing leukemia but can convert to an acute type that’s harder to treat.
Acute lymphocytic leukemia (ALL)
Acute lymphocytic leukemia occurs in both children and adults. It is the most common type of leukemia in children; about three-quarters of leukemia patients under age 20 are diagnosed with ALL, and most childhood cases appear before the ages of 2 and 4. About 40 percent of people diagnosed with ALL are adults. With ALL, your bone marrow produces too many of the white blood cells called lymphocytes. This type of leukemia usually progresses quickly if it’s not diagnosed and treated right away.
Chronic lymphocytic leukemia (CLL)
CLL is the most common type of leukemia in adults, especially seniors, while it is uncommon in people under 40, and rare in children. Exposure to the pesticide Agent Orange has been linked to CLL. Some cases of CLL have slow-growing cells, while others have faster-growing cells. For slow-growing CLL, your doctor may recommend watchful waiting without immediate treatment. People with the fast-growing CLL may need treatment sooner.
How doctors predict the course of your leukemia
Several factors can affect your disease prognosis, such as specific chromosomal changes and whether certain specific gene mutations are identified. That’s why it is so important to find the right oncologist and medical center to help with your diagnosis and match your treatment to your specific situation. A high white cell count at the time of diagnosis may signal a poorer chance of survival. Being older or having a prior blood disorder may also mean a poorer prognosis.
Leukemia knowledge is power
Understanding more about the type of leukemia you have can help you make treatment decisions. Even if you do have a faster-growing type, or a delayed diagnosis and signs of disease spread, clinical trials and research offer hope. Using a cancer center that specializes in leukemia is also crucial for the latest treatments and better outcomes. To help you and your family make it through your journey with leukemia, take advantage of support options and advocacy organizations in your area.