Leukemia is a type of cancer that affects the blood and bone marrow, characterized by the uncontrolled proliferation of abnormal white blood cells. It is broadly classified into acute and chronic forms, based on the progression and nature of the disease.
Acute Leukemia
Characteristics:
- Rapid Onset: Acute leukemia progresses quickly and requires immediate treatment. Symptoms can develop over weeks to months.
- Immature Cells: It involves the proliferation of immature blood cells (blasts) that do not function properly.
- Bone Marrow Involvement: The bone marrow is rapidly filled with these immature cells, leading to decreased production of normal blood cells.
Types:
- Acute Lymphoblastic Leukemia (ALL):
- Affects lymphoid cells. Common in children but can occur in adults.
- Symptoms include fatigue, bleeding, bone pain, and frequent infections.
- Acute Myeloid Leukemia (AML):
- Affects myeloid cells. More common in adults but can also occur in children.
- Symptoms include fatigue, fever, bleeding, and infections.
Diagnosis:
- Blood Tests: Elevated white blood cell count with a high proportion of immature cells (blasts).
- Bone Marrow Biopsy: Confirmation of leukemia cells and evaluation of the extent of bone marrow involvement.
- Cytogenetic and Molecular Testing: Identifies specific genetic mutations or abnormalities.
Treatment:
- Chemotherapy: Intensive treatment to eliminate leukemia cells.
- Targeted Therapy: Drugs that target specific genetic mutations or characteristics of leukemia cells.
- Bone Marrow Transplant (Stem Cell Transplant): In some cases, to replace diseased bone marrow with healthy stem cells.
Chronic Leukemia
Characteristics:
- Slow Onset: Chronic leukemia progresses more slowly compared to acute forms, with symptoms developing over months to years.
- Mature Cells: Involves the proliferation of more mature, but still abnormal, blood cells.
- Bone Marrow and Blood Involvement: The disease often affects both the bone marrow and blood, but may not always cause immediate symptoms.
Types:
- Chronic Lymphocytic Leukemia (CLL):
- Affects mature lymphocytes. Most common in older adults.
- Symptoms can be mild initially, including swollen lymph nodes, fatigue, and infections.
- Chronic Myeloid Leukemia (CML):
- Affects mature myeloid cells. Characterized by the Philadelphia chromosome, which results from a genetic translocation.
- Symptoms include fatigue, weight loss, splenomegaly (enlarged spleen), and night sweats.
Diagnosis:
- Blood Tests: Elevated white blood cell count with a predominance of mature or partially mature cells.
- Bone Marrow Biopsy: Evaluates the extent of disease involvement in the marrow.
- Genetic Testing: Identifies specific chromosomal abnormalities, such as the Philadelphia chromosome in CML.
Treatment:
- Targeted Therapy: Drugs such as tyrosine kinase inhibitors (e.g., imatinib for CML) that specifically target cancer cells.
- Chemotherapy: May be used in combination with targeted therapies or as initial treatment.
- Immunotherapy: Uses the body’s immune system to fight cancer cells.
- Bone Marrow Transplant: Considered in some cases, especially if other treatments are ineffective.
Summary
- Acute Leukemia involves rapid proliferation of immature cells, requires immediate treatment, and is categorized into ALL and AML.
- Chronic Leukemia involves more mature cells, progresses slowly, and is categorized into CLL and CML. Treatment often includes targeted therapies and long-term management strategies.