Leukæmi

Leukæmi, or leukemia, is a group of cancers that originate in blood-forming tissues, most often the bone marrow and lymphatic system. In leukemia, certain white blood cells acquire genetic changes that cause rapid, uncontrolled growth and impaired maturation, leading to crowding out of normal blood cells. This can result in anaemia, increased infection risk, and problems with bleeding or bruising. Leukemias are broadly categorized as acute or chronic, depending on how quickly the disease progresses and the maturity of the malignant cells, and by lineage, lymphoid or myeloid.

The four main forms are acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), and chronic myeloid leukemia (CML). ALL and AML typically present with rapid symptoms and require urgent treatment, while CLL and CML often progress more slowly but can vary in aggressiveness and may still require therapy.

Symptoms commonly include fatigue, pallor, frequent infections, fever, easy bruising or bleeding, weight loss, bone or joint pain, and enlarged lymph nodes or spleen. Diagnosis relies on blood tests and examination of bone marrow, including complete blood count, peripheral smear, marrow biopsy, immunophenotyping, and genetic/molecular testing to define subtype and guide treatment.

Treatment is tailored to subtype, age, and overall health. It may include chemotherapy, targeted therapies (such as BCR-ABL inhibitors for CML and other agents for specific mutations), immunotherapies (including monoclonal antibodies and CAR-T cells), and, in some cases, allogeneic stem cell transplantation. Prognosis varies widely by subtype, with high cure rates in many pediatric cases and more variable outcomes in adults.