Leukemia

Leukemia is a type of blood cancer that begins in the bone marrow and is characterized by the abnormal proliferation of blood cells. White blood cells, in particular, multiply uncontrollably, disrupting the normal structure and function of blood in the body. Leukemia can occur at any age, from childhood to old age, and has different subtypes. These subtypes are important in terms of the disease’s course, treatment, and prognosis.

Leukemia arises from genetic changes in stem cells that cause rapid proliferation of abnormal white blood cells. These blood cells do not mature or function properly; instead, they spread into the bone marrow and blood, inhibiting the production of healthy blood cells. Leukemia types are generally divided into two main groups: acute and chronic.

• Acute Leukemia: The disease progresses rapidly with a high increase in immature cells (blasts). Prompt diagnosis and treatment are critical in acute leukemia. It includes two types:
• • Acute Myeloid Leukemia (AML)
  • Acute Lymphoblastic Leukemia (ALL): Composed of immature lymphoid cells called lymphoblasts. It is especially common in childhood.
• Chronic Leukemia: The disease progresses more slowly, and mature cells retain partial function. Chronic leukemia can be controlled for years. The most common types are:
• • Chronic Myeloid Leukemia (CML)
  • Chronic Lymphocytic Leukemia (CLL)

Leukemia symptoms mostly result from the lack of healthy blood cells in the body. The most common complaints include:

• Fatigue and weakness: Due to a decrease in red blood cells (anemia).
• Frequent infections: Caused by dysfunctional white blood cells leading to weakened immunity.
• Easy bruising and bleeding: Due to low platelet counts which reduce blood clotting ability.
• Bone and joint pain
• Swelling of lymph nodes
• Fever and night sweats
• Abdominal swelling (due to enlargement of the liver or spleen)

The exact causes of leukemia are not fully understood, but some genetic and environmental factors increase the risk:

• Genetic factors: Certain inherited disorders like Down syndrome increase leukemia risk.
• Exposure to radiation: High doses of radiation may increase the chance of developing leukemia.
• Chemical exposure: Long-term contact with chemicals like benzene is a risk factor.
• Chronic blood disorders: Some blood diseases can transform into leukemia.

Initially, blood tests are performed to diagnose leukemia. A complete blood count (CBC) gives clues about the presence of leukemic cells. A definitive diagnosis requires a bone marrow biopsy. The sample taken from the bone marrow is examined under a microscope to determine the leukemia cell type.

Recently, molecular tests and genetic analyses have played an important role in accurately identifying leukemia subtypes and predicting treatment response.

Leukemia treatment varies according to the type, stage of the disease, patient age, and overall health. Commonly used treatments include:

• Chemotherapy: Uses drugs to kill cancer cells. In acute leukemia, chemotherapy is applied rapidly and intensively.
• Targeted therapy: Especially in chronic myeloid leukemia, drugs targeting specific molecular markers (e.g., tyrosine kinase inhibitors) are used.
• Radiotherapy: Applied in some cases to control the spread of leukemic cells.
• Bone marrow (stem cell) transplant: Used in high-risk or treatment-resistant cases to replace damaged cells with healthy ones.

Recent developments in nanotechnology have brought hope in leukemia diagnosis and treatment. Nanoparticles enhance drug delivery directly to cancer cells, increasing treatment effectiveness and reducing side effects. Furthermore, genetic diagnostic techniques and biomarkers have enabled early detection and personalized treatment options.

Many factors affect the course of leukemia. Early diagnosis and appropriate treatment improve prognosis. The disease type, genetic characteristics, treatment response, and overall health status of the patient are critical in treatment success. Thanks to advances in treatment, especially in childhood acute leukemias, high cure rates are now achievable.