What is Leukemia? Types, Causes, Symptoms, and Treatments

Leukemia is a type of cancer that affects the blood cells. This condition can develop in people of any age, but it most often affects either children or older adults. Experts estimate that within the United States, there are more than 472,000 people who have leukemia. Globally, about 2.43 million people are living with the condition. Around 1.5% of people will develop leukemia during their life.

Leukemia types and survival rates

here are several types of leukemia. Different forms of this cancer are grouped into categories based on how fast they grow: acute leukemias consist of abnormal-looking cells that grow aggressively, while chronic leukemias consist of cancer cells that look more normal and grow more slowly.

Leukemias are also classified by the type of blood cell they affect. Lymphoblastic or lymphocytic leukemias form in the cells that make lymphocytes, which arewhite blood cells that fight infections. Myeloid or myelogenous leukemias develop from the cells that make red blood cells, platelets, and other types of white blood cells.

Overall, there are four main types of leukemia. They each lead to different outlooks:

• Acute lymphoblastic leukemia (ALL). Around 70.8% of people with ALL live five years or more after diagnosis.
• Acute myeloid leukemia (AML). About 30.5% of people with AML live at least five years after diagnosis.
• Chronic lymphocytic leukemia (CLL). About 87.9% of people with CLL live five years or more after being diagnosed.
• Chronic myeloid leukemia (CML). Around 70.4% of people with CML live at least five years after being diagnosed.

Each of these leukemia types also consists of multiple subtypes. The type of leukemia you have determines which symptoms you develop and plays a role in which treatment plan has the best chance of being the most effective.

Leukemia causes

Cancer, including leukemia, develops due to changes (mutations) in a cell’s genes. Genes act like instructions that tell the cell what to do and how to grow. When genes in a blood cell undergo mutations, they may tell the cell to start growing too quickly or make too many copies of itself, leading to large numbers of abnormal leukemia cells that crowd out the body’s normal blood cells.

Experts don’t always understand why these mutations form. However, certain risk factors can increase your chances of developing gene changes that lead to leukemia, such as:

• Being exposed to certain chemicals, including benzene and formaldehyde.
• Smoking cigarettes.
• Having previously undergone cancer treatments such as radiation therapy or chemotherapy.
• Having certain genetic disorders like Down syndrome, Klinefelter syndrome, or Fanconi anemia.
• Being diagnosed with other conditions that affect blood cells, such as myelodysplastic syndrome (MDS) or a type of myeloproliferative neoplasm (MPN).
• Having a family history of leukemia.

In most cases, it’s not clear what exactly caused your leukemia. However, doctors can look for specific gene mutations that may provide clues about which treatments may work best.

Leukemia symptoms

Symptoms of leukemia can include:

If you have leukemia, you may not experience all of these symptoms. Some types of leukemia, especially chronic leukemias, may not cause any symptoms at all in the early stages.

Leukemia treatments

The treatment options your doctor recommends depend on several factors, such as how old you are, whether you have other health conditions, the type of leukemia you have, and what your personal preferences are. However, leukemia is generally treated with a few main types of treatments.

• Chemotherapy. These medications destroy cancer cells or prevent them from making new copies of themselves. Chemotherapy drugs may come in the form of a pill that is taken by mouth or a liquid that is given through an injection or IV. A combination of different types of chemotherapy is often recommended as an initial treatment for leukemia.
• Targeted therapy. Targeted therapy drugs block specific molecules found on your cancer cells, preventing them from growing while largely leaving your body’s normal cells alone. Targeted therapies are the main treatment option for people with CML. They may also be used to treat other types of leukemia, depending on what types of genetic mutations are present.
• Radiation therapy. During radiation therapy, beams of energy are used to kill cancer cells. Radiation treatments are not often used for people with leukemia but may be used in certain situations. This treatment may ease symptoms when large numbers of leukemia cells collect within a certain tissue, such as the bones or the spleen. Radiation therapy may also help treat acute leukemias that have spread to the brain or spinal cord.
• Immunotherapy. Immunotherapy includes multiple different types of treatments that can strengthen your immune system’s ability to fight leukemia. Types of immunotherapies include medications like interferons or interleukins, or procedures like chimeric antigen receptor (CAR) T-cell therapy, in which your immune cells are genetically engineered to better recognize and kill leukemia cells. Monoclonal antibodies are medications that can be considered forms of both immunotherapy and targeted therapy.
• Hematopoietic stem cell transplant. This procedure, also called a bone marrow transplant, involves first killing your blood cells with high doses of chemotherapy or radiation therapy. Then, you receive an infusion of stem cells, which help create new, healthy blood cells. These stem cells may be your pre-treated cells, or they may come from a donor.

If you think you have leukemia, talk to your doctor or a hematologist/oncologist. Although leukemia is a serious condition, there is hope. Researchers are constantly discovering new treatment options, allowing people with leukemia to live longer than ever before.