According to the National Cancer Institute, 1.5 percent of Americans will be diagnosed with leukemia at some point in their lives. Leukemia is the most common type of cancer in children under age 15 and the most common blood cancer in people older than 55 in the United States. In 2017, there were 434,982 Americans living with leukemia.

What Is Leukemia?

Leukemia is a type of blood cancer that begins in the bone marrow when blood stem cells develop abnormally. When these abnormal cells begin to invade nearby tissues or break off and migrate to other locations, they have become cancerous.

What Causes Leukemia?

Like all cancer, leukemia is caused by genetic mutations that allow cells to divide and grow in a disorganized way. Most cancer is caused by acquired mutations that occur over a person’s life. It is uncommon for leukemia to run in families.

Men and non-Hispanic white people are the groups with the highest risk for developing leukemia. Other risk factors that increase the risk for leukemia include:

• Older age
• High doses of radiation
• Exposure to chemicals such as benzene
• Obesity
• Certain rare genetic disorders

Read more about risk factors and causes of leukemia.

How Is Leukemia Diagnosed?

There are no screening exams that can catch leukemia early. Since leukemia symptoms may be mistaken for the flu or another common illness, leukemia is often diagnosed when routine blood tests return abnormal results. Once leukemia is suspected, doctors order tests to confirm the diagnosis and to establish the specific type of leukemia, along with details that will inform recommendations for treatment.

Tests used to diagnose leukemia may include:

• Physical exam
• Laboratory tests on blood samples, including complete blood count, blood smear, and blood chemistry
• Cytogenetic analysis to determine specific genetic mutations on leukemia cells
• Bone marrow biopsy or bone marrow aspiration
• Imaging tests such as X-rays, computed tomography (CT), or magnetic resonance imaging (MRI)

Read more about tests to diagnose leukemia.

What Are the Symptoms of Leukemia?

Symptoms of leukemia can vary by your age and type of leukemia. Some of the most common symptoms of leukemia across all types are:

• Fatigue
• Shortness of breath
• Fever
• Night sweats
• Bruising or bleeding easily
• Bone pain
• Joint pain
• Frequent infections

Read more details about symptoms of leukemia.

What Are the Different Types of Leukemia?

Each case of leukemia is either acute or chronic. Acute leukemia grows rapidly and requires immediate treatment, while chronic leukemia grows more slowly and may not need to be treated right away. Leukemias are also categorized based on the type of white blood cells involved and their stage of maturity. Finally, each case of leukemia may be further classified based on the specific genetic mutations found during cytogenetic analysis of cancer cells.

The four main types of leukemia are:

• Acute lymphoblastic leukemia (ALL — also called acute lymphocytic leukemia)
• Acute myeloid leukemia (AML — also called acute myelogenous leukemia)
• Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL)
• Chronic myeloid leukemia (CML)

There are dozens of subtypes of these four types. CLL/SLL is assigned stages, but most leukemia is not. Cases of CML are described by phases. There are several rare types of leukemia that don’t fall neatly into any of the categories above, and some types of leukemia may also be classified as another form of blood cancer, such as lymphoma or myeloproliferative neoplasms (MPNs).

Read more about types of leukemia.

How Is Leukemia Treated?

Many types of treatment are used to fight leukemia. Depending on the type of leukemia you have, treatment options may include chemotherapy, immunotherapy, targeted therapies, radiation therapy, and stem cell transplantation. Some people with leukemia choose to participate in clinical trials.

Your doctor will recommend treatment options based on several different factors, including which type of leukemia you have. Your age and overall health may also be important factors in finding the best leukemia treatment for you. Treatments may be combined in a treatment plan or used alone as a single treatment, known as monotherapy.

In cases of acute leukemia, treatment needs to begin immediately. Chronic leukemia grows more slowly and may not require treatment right away. The goals of leukemia treatment may also differ from case to case. A cure may be possible for many cases of acute leukemia, but treatments for chronic leukemia may focus on achieving remission and preventing relapses, or simply slowing the growth of cancer.

Read more about treatments for leukemia.

How Do Other Health Conditions Affect Leukemia?

When someone has more than one health condition at the same time, the conditions are known as comorbidities. Comorbid conditions may be related to leukemia in different ways. If you have other health conditions as well as leukemia, these comorbidities can lower your tolerance for leukemia treatment and limit your treatment options. For these reasons, having comorbidities may influence your leukemia prognosis.

Other health conditions may be more likely to develop after leukemia treatment. Your doctor can help you better understand your individual risk factors for developing related conditions and recommend steps to lower your risk.

Read more about other health conditions related to leukemia.

What Is the Prognosis for Leukemia? Can It Be Cured?

New ways of treating leukemia have increased survival rates and rates of cure and remission over the past 10 years. Whether a cure is possible depends on many factors relating to your specific case of leukemia, treatment options available to you, and your age and overall health. Many cases of acute leukemia can now be cured, but the goal in treating chronic leukemia may be to achieve remission and prevent relapses or slow the rate of cancer growth. Averaged across all types of leukemia and all ages and other factors, the five-year relative survival rate after a leukemia diagnosis is 63.7 percent in the U.S. This means that more than three-fifths of Americans diagnosed with leukemia are still alive after five years.

Leukemia Condition Guide

• Types of Leukemia
• What Causes Leukemia?
• Symptoms of Leukemia
• Leukemia — The Path to Diagnosis
• Treatments for Leukemia
• Conditions Related to Leukemia