Leukemia is a group of cancers that begin in blood-forming tissues, causing abnormal blood cells to grow and interfere with normal blood-cell production.
Leukemia is not one single disease. It is a group of blood and bone-marrow cancers classified according to the blood-cell lineage involved and how quickly the disease develops. Major types include acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML) and several less common forms.
Bone marrow is the main blood-forming tissue where abnormal leukemia cells develop. Blood carries these cells throughout the body, and the lymphatic system, spleen, liver and other organs may become involved depending on the subtype.
Leukemia begins when genetic changes in a blood-forming cell cause abnormal growth and survival. The altered cells can accumulate in bone marrow and blood and progressively interfere with normal blood-cell production.
Abnormal blood-forming cells multiply in the bone marrow and blood. They can crowd out normal red blood cells, platelets and healthy white blood cells, leading to anemia, bleeding or bruising, infections and other complications.
Leukemia is broadly classified by cell lineage and disease tempo. Acute leukemias progress rapidly and include ALL and AML. Chronic leukemias generally progress more slowly and include CLL and CML. Additional subtypes are defined using morphology, immunophenotype, chromosome changes and molecular abnormalities.
Major leukemia categories include acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL) and chronic myeloid leukemia (CML). Other rarer leukemias include hairy cell leukemia and several lineage-specific entities.
Persistent fatigue or weakness
Pale skin or pallor
Fever or recurrent infections
Easy bruising or unexplained bleeding
Small red or purple skin spots called petechiae
Bone or joint pain
Swollen lymph nodes
Unexplained weight loss
Night sweats
Abdominal fullness from an enlarged spleen or liver
Shortness of breath related to anemia or illness
The exact cause of most leukemia cases is unknown. Risk can be influenced by certain inherited conditions, previous chemotherapy or radiation exposure, some chemical exposures and specific genetic or chromosomal abnormalities.
Increasing age for several adult leukemia subtypes
Previous chemotherapy
Previous radiation therapy or substantial radiation exposure
Certain inherited syndromes such as Down syndrome
Smoking, particularly for some myeloid leukemias
Certain occupational chemical exposures
Family history may increase risk for selected leukemia types
Certain pre-existing blood disorders
Evaluation may include medical history, physical examination, complete blood count with differential, peripheral blood smear, bone-marrow aspiration or biopsy, flow cytometry, cytogenetic studies and molecular testing. Imaging may be used when organ involvement or complications need evaluation.
Pallor or signs of anemia
Fever or signs of infection
Bruising or petechiae
Unusual bleeding
Enlarged lymph nodes
Enlarged spleen or liver
Bone or joint tenderness
General weakness or weight loss
Complete blood count (CBC) with differential
Peripheral blood smear
Bone marrow aspiration
Bone marrow biopsy
Flow cytometry / immunophenotyping
Cytogenetic and chromosome testing
Molecular and genetic testing
Coagulation tests when bleeding risk is present
Blood chemistry and organ-function tests
Chest imaging when clinically indicated
Ultrasound or other imaging for organ enlargement
CT scan when specific complications or organ involvement need assessment
MRI or other specialized imaging when clinically indicated
BCR::ABL1 testing for suspected CML or selected ALL cases
Molecular mutation testing for subtype and treatment planning
Minimal / measurable residual disease testing when applicable
HLA typing when stem-cell transplantation may be considered
Lumbar puncture with cerebrospinal-fluid testing in selected leukemia settings
Viral infections causing temporary blood-count abnormalities
Aplastic anemia
Myelodysplastic syndromes
Other blood cancers
Immune thrombocytopenia or other platelet disorders
Other causes of unexplained lymph-node enlargement
Severe nutritional or inflammatory blood disorders
Leukemia is generally not staged like most solid tumors. Instead, doctors classify the leukemia by subtype, disease burden, genetic or molecular characteristics, risk group and treatment response. Chronic lymphocytic leukemia can use specific staging systems.
Staging or grading systems differ between diseases. The information here is educational and should be interpreted by a qualified healthcare professional in the context of the individual case.
Treatment depends on the leukemia subtype and risk profile. Options may include chemotherapy, targeted therapy, immunotherapy, supportive transfusions and infection treatment, and hematopoietic stem-cell transplantation for selected patients. Some chronic leukemias may initially be monitored when immediate treatment is not required.
Chemotherapy medicines selected according to leukemia subtype and risk
Targeted therapy such as tyrosine-kinase inhibitors for selected molecular abnormalities
Monoclonal antibodies or other immunotherapies for selected leukemia types
Corticosteroids in specific leukemia treatment protocols
Supportive antibiotics, antifungals or antivirals when clinically indicated
Red-cell or platelet transfusions and other supportive treatments when required
Medicines listed here are for educational information only. Do not start, stop, or change a medicine without professional medical advice.
Possible complications include severe infection, anemia, bleeding, thrombosis in selected settings, tumor lysis syndrome during treatment, organ involvement, treatment-related toxicity and relapse. Some complications can become medical emergencies.
Fever during chemotherapy or severe immune suppression
Uncontrolled bleeding, vomiting blood or black stools
Severe shortness of breath or chest pain
New confusion, seizure, severe headache or sudden neurologic symptoms
Rapidly worsening weakness, fainting or severe dizziness
Severe abdominal pain or rapidly worsening illness
If symptoms are severe, rapidly worsening, or life-threatening, seek emergency medical care immediately.
Prognosis varies substantially between leukemia types and individual patients. Important factors include age, subtype, chromosome and molecular findings, initial blood counts, response to treatment, measurable residual disease where applicable and overall health.
Survival statistics describe outcomes in groups of people and cannot predict exactly what will happen to one individual. Prognosis depends on factors such as cancer stage, tumor biology, treatment response, overall health, and follow-up.
Leukemia can occur at any age. Different subtypes have different age patterns: ALL is common in children, while several chronic leukemias are more common in adults. AML can occur across the lifespan but is more common with increasing age.
Most leukemia cases cannot be prevented. General risk reduction includes avoiding tobacco, following occupational safety measures and minimizing unnecessary exposure to ionizing radiation and known harmful chemicals.
What type and subtype of leukemia is present?
What blood and bone-marrow findings confirm the diagnosis?
Are chromosome or molecular abnormalities present?
What is the risk category and what does it mean?
What treatment is recommended and why?
Are targeted or immunotherapy options appropriate?
Will measurable residual disease testing be used?
Should stem-cell transplantation be considered?
What side effects require immediate medical attention?
What follow-up tests and schedule are needed?
BimariDur provides educational health information to help people understand diseases, symptoms, tests, and treatment concepts. It does not replace examination, diagnosis, or treatment by a qualified healthcare professional.
Do not delay professional medical care because of information read on BimariDur.