Leukemia: Types, Symptoms, Diagnosis, and Treatment
Author: Disabled World (DW)
Updated/Revised Date: 2 Nov 2026
Table of Contents:
Synopsis - Definition - About This Section - FAQs - Publications - Subtopics
Synopsis
Learn how leukemia, a group of blood cancers that begins in the bone marrow, develops, plus its four main types, symptoms, diagnosis, and treatment options.
At a Glance
- 1 - Immature leukemia cells are known as blasts.
- 2 - About 67,790 people in the United States will be diagnosed with leukemia in 2026.
- 3 - The four main types are grouped as acute or chronic and as lymphocytic or myelogenous, depending on speed and cell line.
- 4 - Gleevec, also called STI-571, was the first targeted therapy approved for chronic myeloid leukemia, blocking leukemia cells while sparing others.
Topic Definition
- Leukemia
Leukemia is a group of cancers that usually starts in the bone marrow, the soft tissue at the center of most bones where blood cells are made, and results in large numbers of abnormal white blood cells. Because these cells, called blasts or leukemia cells, never fully mature, they crowd out the healthy red cells, white cells, and platelets the body depends on, which leads to problems such as fatigue, fever, easy bruising or bleeding, and a greater risk of infection. Doctors describe the disease as either acute, meaning it worsens quickly, or chronic, meaning it progresses slowly, and they further group it by whether it begins in lymphoid or myeloid cells, giving rise to four common types. Its exact causes are not known, though high radiation exposure, certain chemicals, some genetic conditions, and prior chemotherapy can raise the risk. Diagnosis usually comes through blood tests or a bone marrow biopsy, and treatment may combine chemotherapy, biological therapy, radiation, targeted therapy, and stem cell transplantation.
Overview
Defining Leukemia
Leukemia is a group of cancers that usually begins in the bone marrow and results in high numbers of abnormal white blood cells. These white blood cells are not fully developed and are called blasts or leukemia cells. Symptoms may include bleeding and bruising problems, exhaustion, fever, and an increased risk of infections. These symptoms occur due to a lack of normal blood cells. Diagnosis is typically by blood tests or bone marrow biopsy.
The U.S. Social Security Administration (SSA) has included Acute Leukemia as a Compassionate Allowance to expedite a disability claim.
A person's blood cells are formed in their bone marrow, a soft material in the center of most of their bones. Blood cells that have yet to mature are called 'Stem Cells' and 'Blasts.' Most of a person's blood cells mature in their bone marrow before moving into blood vessels. Blood that flows through a person's blood vessels and heart is called 'Peripheral Blood.' Bone marrow produces various blood cells, each with a specific function.
The bone marrow in persons with Leukemia produces abnormal white blood cells referred to as 'Leukemia Cells.' From the first appearance, these cells seem to function fairly well. Over time, Leukemia cells may begin to outnumber other cells, such as red blood cells, white blood cells, and platelets, making it difficult for blood to function properly.
Types of Leukemia
Leukemia is described as acute, meaning it develops and worsens quickly, or chronic, meaning it develops slowly. It is also grouped by the type of white blood cell affected: lymphoid cells (lymphocytic or lymphoblastic leukemia) or myeloid cells (myeloid or myelogenous leukemia). This gives four main types. The American Cancer Society estimates that about 67,790 people in the United States will be diagnosed with leukemia in 2026 and about 23,910 will die from it [Siegel et al., 2026].
- Acute Lymphocytic Leukemia (ALL): the most common cancer in children, though it also affects adults. About 6,250 new cases are expected in 2026.
- Acute Myeloid Leukemia (AML): mainly affects adults, especially older adults, and accounts for about 1 in 3 leukemias in adults. About 22,720 new cases are expected in 2026, and it causes the most leukemia deaths, about 11,500.
- Chronic Lymphocytic Leukemia (CLL): the most common leukemia in adults in Western countries. It mainly affects older adults, with an average age at diagnosis of around 70, and very rarely affects children. About 22,760 new cases are expected in 2026.
- Chronic Myeloid Leukemia (CML): mainly affects adults and accounts for about 15 percent of leukemias in adults. It is caused by a gene change called the Philadelphia chromosome (BCR-ABL).
Less common types include hairy cell leukemia, chronic myelomonocytic leukemia, and adult T-cell leukemia/lymphoma.
Risk Factors for Leukemia
The cause of most cases of leukemia is not known. Things that raise the risk include:
- High levels of radiation: such as from atomic bomb explosions or nuclear accidents, and radiation therapy for an earlier cancer. Low doses from diagnostic X-rays have not been clearly linked to leukemia.
- Certain chemicals: long-term exposure to benzene, which is found in cigarette smoke, gasoline and some industrial settings, and formaldehyde.
- Smoking: raises the risk of AML.
- Earlier chemotherapy: some drugs, such as alkylating agents, can cause leukemia years later.
- Genetic conditions: such as Down syndrome, Li-Fraumeni syndrome and Fanconi anemia.
- Blood disorders: myelodysplastic syndromes and myeloproliferative neoplasms can develop into AML.
- HTLV-1 virus: can cause adult T-cell leukemia/lymphoma. The virus can be passed on through blood, sexual contact and breastfeeding, but leukemia itself is not contagious.
- Family history: having a close relative with CLL raises the risk of CLL.
Studies have not shown a convincing link between leukemia and the weak electromagnetic fields from power lines and electrical appliances.
Symptoms of Leukemia
Leukemia cells crowd out the healthy blood cells in the bone marrow, so symptoms come from too few healthy cells: tiredness, weakness and shortness of breath from anemia; frequent or severe infections and fever from too few working white blood cells; and easy bruising, bleeding gums, nosebleeds or tiny red spots on the skin (petechiae) from too few platelets. Other symptoms can include night sweats, weight loss, bone or joint pain, swollen lymph nodes, and a swollen spleen or liver that causes fullness under the left ribs.
Acute leukemia causes symptoms that appear and worsen over days or weeks. Leukemia cells can also collect in the brain and spinal cord, causing headaches, vomiting or seizures, or in the testicles, gums or skin. Chronic leukemia often causes no symptoms for years and is frequently found on a routine blood test. These symptoms have many other causes, so see a doctor to find out what is causing them.
Diagnosing Leukemia
- Physical exam: the doctor looks for pale skin, bruising, and swollen lymph nodes, liver and spleen.
- Blood tests: a complete blood count shows the numbers of white cells, red cells and platelets, and a blood smear shows whether there are abnormal or immature cells (blasts).
- Bone marrow aspiration and biopsy: a needle removes a small amount of liquid marrow and a small core of bone, usually from the back of the hip bone, under local anesthesia.
- Laboratory tests on the leukemia cells: flow cytometry, cytogenetics (chromosome tests) and molecular tests find the exact type of leukemia and gene changes, such as the BCR-ABL gene in CML or FLT3 and IDH mutations in AML, that guide treatment and predict outcome.
- Spinal tap (lumbar puncture): checks the fluid around the brain and spinal cord for leukemia cells, mainly in ALL.
- Imaging: such as a chest X-ray, CT scan or ultrasound.
Treatment of Leukemia
People with leukemia should be treated at a center with doctors experienced in the disease: hematologists, medical oncologists and, for children, pediatric hematologist-oncologists. The National Cancer Institute's Cancer Information Service (1-800-4-CANCER) can help find treatment centers and clinical trials. Treatment depends on the type of leukemia, gene changes in the leukemia cells, the person's age and general health, and whether the leukemia has been treated before.
Acute leukemia needs prompt treatment, usually starting with intensive therapy to bring about a remission (no signs of leukemia), followed by more treatment to stop it from coming back. Many children and some adults with acute leukemia are cured. Chronic leukemia without symptoms may not need treatment right away; with CLL, doctors often watch and wait with regular checkups. Chronic leukemia is rarely cured, but modern treatment can control it for many years.
- Chemotherapy: drugs given by mouth, into a vein (often through a long-term catheter or port), or into the spinal fluid (intrathecal chemotherapy, sometimes through an Ommaya reservoir under the scalp). It is given in cycles of treatment and rest.
- Targeted therapy: drugs that attack specific features of leukemia cells. Imatinib (Gleevec), approved in 2001, and newer tyrosine kinase inhibitors such as dasatinib, nilotinib and asciminib have turned CML into a long-term, controllable condition for most people. BTK inhibitors such as ibrutinib and acalabrutinib, and the BCL-2 inhibitor venetoclax, are standard treatments for CLL. Targeted drugs for FLT3, IDH1 and IDH2 mutations are used in AML.
- Immunotherapy: monoclonal antibodies such as rituximab and obinutuzumab for CLL, and blinatumomab and inotuzumab for ALL.
- CAR T-cell therapy: a person's own T cells are genetically changed in a laboratory to attack leukemia cells and then given back. The U.S. Food and Drug Administration approved the first CAR T-cell therapy, for children and young adults with ALL, in 2017.
- Stem cell transplant: high-dose chemotherapy, sometimes with total body radiation, destroys the bone marrow, which is then replaced with healthy blood-forming stem cells. Stem cells can come from a donor (allogeneic transplant), from an identical twin (syngeneic), from umbilical cord blood, or less often from the person's own blood or marrow (autologous transplant). Donor transplants can cure some leukemias.
- Radiation Therapy: used to treat leukemia in the brain or a swollen spleen, or to prepare for a stem cell transplant.
- Supportive care: blood transfusions, antibiotics and medicines to prevent infection, and treatment for pain, nausea and emotional distress are an important part of care at every stage.
Side Effects of Treatment
Chemotherapy can cause tiredness, infections, bruising and bleeding, hair loss, mouth sores, nausea, vomiting and diarrhea, and many of these can be prevented or eased with medicine. Some treatments affect fertility, so people who may want children should ask about fertility preservation before treatment starts. Targeted drugs and immunotherapy have their own side effects, such as rashes, heart rhythm problems, or a serious immune reaction called cytokine release syndrome after CAR T-cell therapy. After a donor stem cell transplant, the donor's immune cells can attack the patient's tissues, a condition called graft-versus-host disease (GVHD), which most often affects the skin, liver and digestive tract and can occur months or years later. Steroids and other medicines can help.
Leukemia Survival
About 69 percent of people diagnosed with leukemia in the United States are alive five years later. Survival differs greatly by type: about 33 percent for AML, 71 percent for CML, 73 percent for ALL, and 90 percent for CLL, for people diagnosed from 2016 to 2022 [National Cancer Institute, 2025]. Children with ALL do especially well: about 9 in 10 survive five years or more.
Leukemia Facts and Statistics
- About 67,790 people in the United States will be diagnosed with leukemia in 2026, and about 23,910 will die from it [Siegel et al., 2026].
- Acute lymphocytic leukemia is the most common cancer in children.
- Acute myeloid leukemia causes the most leukemia deaths, about 11,500 expected in 2026.
- Approximately 1.5 percent of men and women will be diagnosed with leukemia at some point during their lifetime.
- Early trials of CAR T cells in 2011 and 2013 led to the first approved CAR T-cell therapy for leukemia in 2017.
Frequently Asked Questions
Is leukemia contagious?
No, leukemia is not contagious and cannot be spread from person to person, and even the rare virus-linked form known as human T-cell leukemia does not pass through everyday contact.
What is the difference between leukemia and lymphoma?
Leukemia usually begins in the bone marrow and mainly affects the blood, while lymphoma starts in the lymphatic system, though both are cancers involving white blood cells.
Can leukemia be cured?
Some people with acute leukemia can be cured once remission is achieved, while chronic leukemia is rarely cured but can often be controlled for a long time with maintenance therapy.
What is the survival rate for leukemia?
Survival varies widely by the type of leukemia, the person's age, and their overall health, so a doctor is best placed to explain the outlook for an individual case.
Is leukemia hereditary?
Leukemia is generally not inherited, though certain genetic conditions such as Down syndrome can raise the risk, and most cases arise without a clear family link.
What are the early warning signs of leukemia?
Early signs can include frequent infections, fever, night sweats, fatigue, easy bruising or bleeding, bone or joint pain, and swollen lymph nodes, though other conditions cause these too.
How is leukemia diagnosed?
Doctors diagnose leukemia through a physical exam, blood tests that measure white cells, hemoglobin, and platelets, and a bone marrow biopsy, sometimes adding a spinal tap or chest X-ray.
What is a bone marrow transplant?
A bone marrow or stem cell transplant replaces diseased bone marrow with healthy blood-forming stem cells, either from a donor or from the patient. It is used for some leukemias, usually after high-dose chemotherapy.
References
- National Cancer Institute, Surveillance, Epidemiology, and End Results Program. (2025). Cancer stat facts: Leukemia (and AML, ALL, CLL and CML pages).
- Siegel, R. L., et al. (2026). Cancer statistics, 2026. CA: A Cancer Journal for Clinicians.
Curated and edited by Ian C. Langtree, Founder and Editor-in-Chief, Disabled World. This section is maintained by the Disabled World editorial team. Last updated: