Get details about our clinical trials that are currently enrolling patients.View Clinical Trials
While there are several types of leukemia, they all start with problems in the creation of blood cells. The body produces millions of blood cells on a daily basis. Most of these blood cells develop in the bone marrow, the spongy interior of the bone that contains immature stem cells.
In a healthy person, these immature stem cells develop through several stages and eventually mature into one of the following cell types:
- White blood cells, which are part of the immune system. There are several types of white blood cells, including granulocytes (most commonly neutrophils) and mononuclear cells (B cells, T cells, NK cells, and monocytes). These cells perform different functions to help your body fight off diseases and infections.
- Red blood cells, which carry oxygen throughout the body
- Platelets, which help the blood clot
Leukemia occurs when the DNA (the genetic instructions that control cell activity) of the stem cells mutates at some point in their development. The cell becomes abnormal and then multiplies uncontrollably. These cancerous cells don’t do their job well and they crowd out healthy cells in the bone marrow and in the bloodstream. This leaves the patient prone to infection, at increased risk for bleeding, weak, and sometimes short of breath.
There are many different types of leukemia, most of which can be grouped into one of two categories: acute and chronic.
- Acute leukemia impacts immature cells, preventing them from developing and carrying out their function. These cells tend to multiply rapidly, making acute leukemia more aggressive.
- Chronic leukemia involves mature or partially mature cells and is slow-growing.
The disease is further broken down by the type of blood stem cell involved:
- Myeloid leukemia (myelogenous leukemia) affects the myeloid cells. When healthy, these stem cells make the immature cells that will become red blood cells, platelets, and most types of white blood cells (not including lymphocytes).
- Lymphocytic leukemia affects the lymphoid cells, which are located in the bone marrow and thymus gland. These stem cells produce immature white blood cells called lymphoblasts. In a healthy person, lymphoblasts mature into white blood cells known as lymphocytes. There are two types of lymphocytes: b cells and t cells. B cell lymphocytes produce the antibodies responsible for attacking invading bacteria and viruses. Some T cell lymphocytes help alert other immune cells to the presence of infection, while others can kill infected cells. Both are essential to the body's immune response.
Types of leukemia
Of the four primary types of leukemia, acute lymphoblastic leukemia (also known as acute lymphocytic leukemia or ALL) is the least common. About 6,000 new cases are diagnosed in the United States each year. While people of all ages develop ALL, a majority of new diagnoses are in people under age 20, making it the most common form of childhood leukemia. The five-year survival rate is 68%.
ALL is an acute form of leukemia that affects the lymphoid stem cells that produce immature white blood cells (lymphoblasts). The diseases lymphoblasts are poor infection fighters, but they divide rapidly and crowd out healthy cells in the bone marrow.
Acute myeloid leukemia (also known as acute myelogenous leukemia or AML) affects myeloid stem cells, which produce red blood cells, granulocytes (a type of white blood cell), and platelets.
AML occurs when a myeloid stem cell becomes cancerous. In these cases, the myeloid stem cells produce diseased cells that do not perform their job but that multiply rapidly. As the disease progresses, the abnormal cells can crowd out healthy cells. There are several subtypes of AML, depending on how different the diseased cells are from normal cells and how far along they are in the development process.
AML may cause patients to develop anemia or have a poor ability to clot blood. It can severely weaken the patient’s immune system, leading to frequent infections.
AML is the most common acute leukemia in adults. While pediatric patients can develop the disease, most diagnoses are in people over age 55. The median age of diagnosis is 68. As an acute leukemia, AML is aggressive and can be particularly difficult to treat. Its five-year survival rate is less than 28%, though that figure differs based on the exact subtype of each person’s cancer.
Specific chromosome abnormalities in the cancer cells and the disease’s own genetic mutations also impact the prognosis.
Chronic lymphocytic leukemia (CLL) is the most common type of adult leukemia, with an estimated 21,000 new cases diagnosed in 2018. The disease is virtually unheard of in children and it primarily affects older adults. Almost 90% of new cases are in people age 55 and older, while the average age at the time of diagnosis is 72.
CLL develops from B cells. B cells start out as lymphoid stem cells, then mature into adult B cells. In CLL, a cancerous B cell grows and multiplies in the bone marrow, lymph nodes, liver, spleen and results in a high white blood cell count. These cancerous cells are not able to fight infection. They also crowd out healthy cells from the marrow and cause enlargement of lymph nodes, liver, and spleen.
As a chronic disease, CLL is less aggressive than acute forms of leukemia. It has a five-year survival rate of around 90%. The presence of specific genetic mutations and proteins produced by the diseased cells, however, can have a big impact on the patient’s prognosis.
For CLL patients, clinical studies have not shown a benefit to beginning treatment immediately after diagnosis. Because of this, doctors often recommend “watchful waiting” for early-stage CLL. During watchful waiting, patients undergo regular blood tests to monitor the disease’s progress. Specifically, doctors look for an increase in leukemia cell count and decrease in hemoglobin and platelet count. Symptoms are treated as they arise. If and when the disease progresses to a set point (called an indication for treatment), initial treatments can include targeted therapy and a combined chemotherapy/immunotherapy treatment.
In most cases, these treatments put patients into remission, meaning most or all of the signs and symptoms of cancer have disappeared. Some patients may need continued treatment to maintain remission. For others, remission is complete and they may stop treatment. All CLL patients in remission are at risk of recurrence, meaning the cancer could come back and require further treatments. Patients typically go through multiple courses of treatment through the span of their disease.
In chronic myeloid leukemia (also known as chronic myelogenous leukemia CML), the myeloid stem cells become cancerous and produce cells that are not fully mature and are poor at doing their jobs. As the disease progresses, the leukemia cells divide uncontrollably and can eventually crowd healthy blood cells out of the bone marrow and get into the blood. This can cause a high white blood cell count and an enlarged spleen.
CML primarily affects adults. About 68% of new cases are in people 55 or older, and the average age of diagnosis is 65. As a chronic disease, CML is relatively slow to develop, and its five-year survival rate is nearly 68%. The patient’s exact subtype of CML can impact his or her prognosis and treatment plan.
While most cases of leukemia fall into one of the four subtypes above, there are other, rarer forms of the disease.
Blastic plasmacytoid dendritic cell neoplasm
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an aggressive subtype of acute leukemia that impacts approximately 500 to 1,000 people in the U.S. a year. Though it can affect people of any age, the disease is most common among older patients, with about half of new diagnoses coming in patients age 70 or older. Historically, it has been associated with poor survival rates.
BPDCN is a cancer of a specific type of cell known as plasmacytoid dendritic cells. This rare type of immune system cell is usually found in the skin, bone marrow, blood, lymph nodes, and spleen. As a result, symptoms usually can impact these areas. Skin lesions are the most common BPDCN symptom. These can show up anywhere on the body but often appear on the arms, legs, face, and neck. Other symptoms include low counts of healthy blood cells and swollen lymph nodes.
Traditionally, BPDCN has been treated with chemotherapy, while younger, fitter patients have been given the option of a stem cell transplant. The FDA has recently approved a new targeted therapy drug that attacks CD123, a molecule commonly found on the surface of BPDCN cells. This targeted therapy is now considered a standard treatment for the disease. Learn more about BPDCN.
Hairy cell leukemia
In hairy cell leukemia, lymphoid stem cells produce too many diseased B cells. Hairy cell leukemia is typically slow to develop and progress. Because of this, doctors often recommend “watchful waiting” in which they simply monitor the disease instead of immediately ordering treatments like chemotherapy or targeted therapy.
T cell prolymphocytic leukemia
T cell prolymphocytic leukemia is an aggressive form of the disease involving lymphoid stem cells, particularly T cells. It is linked to genetic damage that develops during the patient’s lifetime. This damage is not passed down from parent to child. Because the disease is usually aggressive, doctors typically recommend that treatment begins as soon as possible. To know what happens to your blood when you have leukemia, it helps to know what makes up normal blood and bone marrow.
Chronic myelomonocytic leukemia
Chronic myelomonocytic leukemia (CMML) primarily affects older adults, but it can also affect young children. In these cases, the disease is known as juvenile myelomonocytic leukemia (JMML).
CMML is a type of leukemia characterized by the overproduction of cancerous monocytes and the presence of abnormal cells (called blasts) in the bone marrow. Monocytes are a specific type of white blood cell that help fight infections and clean up infected tissues. A common sign of CMML is a high monocyte count in the blood, and about half of all cases cause an enlarged spleen. CMML can be cured with a stem cell transplant, but when this isn't the case, certain drugs can be used to alleviate symptoms.
A risk factor is anything that increases your risk of developing a disease. While there is no way to prevent leukemia, knowing your risk factors can be an important step towards catching the disease early. It's important to note that not everyone with risk factors will develop leukemia.
Risk factors for leukemia include:
- Family history: If a family member has been diagnosed with leukemia, you may be at an increased risk for developing leukemia as well
- Genetic disorders: certain genetic disorders, such a down syndrome, are associated with an increased risk for leukemia
- Smoking, which increases your risk for AML
- Previous cancer treatment: if you have had certain types of chemotherapy or radiation therapy, you may be at increased risk for developing certain types of leukemia
- Exposure to chemicals like benzene
Some cases of leukemia can be passed down from one generation to the next. Genetic counseling may be right for you. Learn more about the risk to you and your family on our genetic testing page.
Learn more about leukemia:
Why choose MD Anderson for your leukemia treatment?
Choosing the right cancer center may be the most important decision you can make as a leukemia patient. At MD Anderson’s Leukemia Center, you’ll get treatment from one of nation’s the largest, most experienced leukemia teams at a top-ranked cancer center.
Using a comprehensive team approach, we work together to give you customized care that includes the most advanced diagnostic methods and treatments. These include clinical trials of new drugs and drug combinations. We offer clinical trials for patients receiving their first treatment through patients who have exhausted all standard treatment options.
As a leading center for leukemia care, we offer access to innovative new therapies and clinical trials that may help increase your chances for successful treatment, many of which were developed by our own researchers.
We are constantly striving to find new and better ways to fight leukemia. We are one of the few cancer centers in the nation to house a prestigious federally funded SPORE (Specialized Program of Research Excellence) focused on leukemia. We offer a wide range of clinical trials and innovative, advanced leukemia treatment for all patients who seek care at MD Anderson.
Treatment Designed Specifically for You
Successful leukemia treatment begins with accurate and precise diagnosis. As many as 15% of leukemia patients have been misdiagnosed before they come to MD Anderson. We have the expertise and experience gained from being one of the most active programs in the world, and our specialized pathologists are highly skilled in diagnosing leukemia.
Our approach to leukemia is customized especially for you. We carefully evaluate your risk factors and the specific characteristics of your leukemia to determine if immediate treatment is necessary. If it is, we recommend the most effective therapies while aiming to limit treatment side effects.
Whether you are treated as an inpatient or outpatient, our comprehensive program offers all the services needed to care for leukemia and its impact on your body. We aim to accomplish as much care as possible on an outpatient basis. If hospitalization is needed, our expert staff is specially trained to handle any complications that may arise.
MD Anderson is my hope. I know that without it, I wouldn’t be alive today.
Leukemia survivor: How I knew MD Anderson was the right choice
Motorcycle racing champion in remission after leukemia clinical trial
Chronic versus acute leukemia: Different diagnoses, different treatments
Maintenance therapy for chronic leukemia: What patients should know
Skin rashes and leukemia: What you need to know
Leukemia survivor: Why I joined a clinical trial
Common leukemia symptoms: What to look for
Clinical trial puts Philadelphia chromosome-positive leukemia survivor in remission
MD Anderson patients have access to clinical trials offering
promising new treatments that cannot be found anywhere else.
Talk to someone who shares your cancer diagnosis and be matched with a survivor.
Prevention & Screening
Many cancers can be prevented with lifestyle changes and regular screening.
Moon Shots Program
MD Anderson’s MDS/AML Moon Shot® and CLL Moon Shot® aim to rapidly and dramatically improve treatment outcomes for leukemia patients through powerful new treatment approaches and research.Learn more about the Moon Shots Program
Due to our response to COVID-19, all blood donations at MD Anderson
Blood Donor Center locations are being held by appointment only.