Definition of Blood Cancer
Blood cancer is also known as leukemia or white blood cell cancer. This disease typically develops in white blood cells and is classified among cancers originating in tissues responsible for blood cell production, including the lymphatic system and bone marrow.[1] White blood cells play a vital role in fighting infections and harmful substances. Normally, these cells grow and divide only as needed by the body. However, in individuals with blood cancer, the bone marrow produces large quantities of abnormal white blood cells that fail to perform their intended functions properly. Many patients experience anxiety, fear, and stress upon receiving a diagnosis of blood cancer. Nevertheless, this condition can be treatable when detected early and managed closely. Despite this, treatment remains complex due to the various types of blood cancer, the absence of clear tumor masses that can be surgically removed, and its rapid spread throughout the body.
Classification of Blood Cancer
Blood cancer is categorized based on the rate of progression and the type of affected blood cells as follows:[2]
- By Progression Rate: This classification depends on how quickly the disease advances and is divided into:
- Acute leukemia: In this stage, white blood cells are immature and remain in early developmental stages. These cells lack functional capacity and divide at an extremely rapid pace, causing the disease to progress very quickly. Immediate, intensive treatment is required, and therapy must begin without delay.
- Chronic leukemia: This form develops slowly and progressively, often remaining undetected for long periods without noticeable symptoms. Symptoms typically appear only after the abnormal cells accumulate significantly, similar to acute leukemia.
- By Type of Affected Cells: The second classification focuses on the specific blood cells involved. Bone marrow contains several distinct types of stem cells that give rise to all blood cell types. Some produce lymphocytes (B and T cells), while others generate myeloid cells that later differentiate into red blood cells, white blood cells, and platelets. The classification includes:
- Lymphocytic leukemia: This type targets lymphocytes in the bone marrow.
- Myeloid leukemia: This form affects myeloid cells within the bone marrow.
Treatment of Blood Cancer
Blood cancer differs fundamentally from other cancers because doctors cannot surgically remove or directly eliminate tumors. As such, scientists consider it a complex condition that is not easily treated. Treatment effectiveness depends on several factors, including the cancer type, extent of spread in the body, patient age, and overall health condition.
Acute leukemia requires immediate treatment. The primary goal is to halt and stop the uncontrolled growth of cancerous cells. When symptoms subside and no signs of disease remain, treatment may continue for an extended period to prevent relapse. This type of blood cancer is one of the forms that can be cured completely.
Patients with chronic blood cancer who have not yet developed symptoms may not require immediate treatment. However, regular monitoring is essential so doctors can track disease progression. Treatment begins once symptoms emerge, aimed at controlling both the illness and its effects. Complete recovery from chronic leukemia is rare.
Most patients with leukemia are treated using chemotherapy—medications designed to destroy cancer cells based on the leukemia subtype. Patients may receive a single drug or a combination of two or more. Other treatments may also be used, such as bone marrow transplantation (BMT), radiation therapy, biological therapy, or a combination. In certain cases, surgical removal of the spleen may be part of the treatment plan.
Chemotherapy
Cancer-fighting drugs are administered intravenously or taken orally, entering the bloodstream to affect cancer cells throughout the body. However, these drugs often do not reach cancer cells in the central nervous system due to the blood-brain barrier—a protective network of blood vessels that filters blood going to the brain and spinal cord. To target cancer cells in the central nervous system, doctors use intrathecal injections, delivering medication directly into the cerebrospinal fluid.
Chemotherapy is delivered in cycles: a treatment phase followed by a recovery period, then another treatment phase, and so on. In some cases, patients receive treatment outside the hospital—such as in outpatient clinics, doctor’s offices, or even at home—depending on the medication type and the patient’s general health. Radiation therapy is often combined with chemotherapy for certain types of leukemia, as high-energy rays damage cancer cells and prevent their growth.
Radiation Therapy
Radiation therapy for blood cancer can be administered in two ways: targeting a specific area of the body where leukemia cells are concentrated—such as the spleen or testicles—or delivering radiation to the entire body, known as total body irradiation. This latter method is commonly used before bone marrow transplantation.
Biological Therapy
Biological therapy involves treatments that influence the body's immune response to cancer. Interferon is one example of biological therapy used against certain types of leukemia.
Stem Cell Transplantation
Some patients with blood cancer may undergo stem cell transplantation. This allows leukemia patients to tolerate high doses of chemotherapy and radiation—or both—which destroy cancerous cells and normal blood cells in the bone marrow. Healthy stem cells are then infused through a flexible tube placed into a large vein in the neck or chest. These transplanted stem cells regenerate new, healthy blood cells.
Symptoms of Blood Cancer
Symptoms vary depending on the type of blood cancer, but common signs include:[3]
- Unintentional weight loss accompanied by reduced appetite.
- Constant severe fatigue and weakness.
- Shivering or fever.
- Frequent infections.
- Sudden swelling of lymph nodes, or enlargement of the spleen or liver.
- Easy bruising or bleeding.
- Shortness of breath during physical exertion or climbing stairs.
- Localized bleeding visible as red spots on the skin.
- Excessive sweating, especially at night.
- Pain and sensitivity in the bones.
Many people overlook these symptoms, mistaking them for flu-like illnesses or other conditions with similar presentations. The severity of symptoms depends on the number of abnormal white blood cells and their location in the body.
Causes of Blood Cancer
Blood cancer is largely hidden and remains poorly understood. Scientists have not yet identified a definitive cause, but evidence suggests it arises from a combination of genetic predispositions and environmental factors.[4]
Acute blood cancer results from cellular instability and dysfunction in white blood cells. These cells lose their normal DNA structure, preventing proper development or maturation. Instead, they accumulate uncontrollably, disrupting the function of healthy cells and ultimately blocking normal blood cell production.
Chronic blood cancer attacks mature cells that multiply slowly, which is why symptoms often go unnoticed until late in the disease. Unfortunately, it remains a fatal condition, and its exact mechanisms are still unknown to experts.
Ultimately, this leads to a shortage of healthy cells, impaired function, increased risk of bleeding, anemia, and widespread disease progression throughout the body. Death usually occurs due to severe blood loss or overwhelming infection.
Diagnosis of Blood Cancer
Often, blood cancer is discovered incidentally during routine blood tests, even before any symptoms appear. When symptoms are present, patients undergo various diagnostic tests, including:[5]
- Blood tests.
- Physical examinations.
- Tests to assess cell formation.
- Bone marrow tests.
- Immune profile analysis.
Multiple tests may be conducted to confirm the diagnosis, determine the specific type of blood cancer, and evaluate how far it has spread. The cancer is categorized into risk levels based on severity and progression, helping doctors tailor an appropriate treatment plan for the individual patient.
Risk Factors
Several factors increase the likelihood of developing certain types of blood cancer (leukemia), including:[5]
- Genetics: Certain inherited genetic conditions can negatively influence cancer development. For example, individuals with Down syndrome have a higher risk of developing blood cancer.
- Cancer Treatment History: People who have undergone chemotherapy or radiation therapy for other cancers are at greater risk of developing blood cancer years later.
- Exposure to Radiation or Specific Chemicals: Individuals exposed to high levels of radiation—such as survivors of atomic explosions or nuclear accidents—are at significantly increased risk. Similarly, exposure to chemicals found in tobacco smoke, fuel, and other sources raises the likelihood of developing the disease.
Not everyone exposed to these risks will develop the disease, and not every person with blood cancer has been exposed to these risk factors.
Special Episode of 'Voices of Pioneers' in Collaboration with Novartis
Discovering Key Facts and Secrets About Leukemia
With Dr. Inas Al-Najjar and Dr. Muhammad Abu Hlila from the Abu Dhabi Stem Cell Center
References
- ↑ "leukemia", National Cancer Institute، Retrieved 24-5-2016. Edited.
- ↑ "leukemia", medicinenet، Retrieved 24-5-2016. Edited.
- ↑ "leukemia", healthline، Retrieved 24-5-2016. Edited.
- ↑ "leukemia", mayoclinic، Retrieved 24-5-2016. Edited.
- ^ أ ب "leukemia", NIH Senior Health، Retrieved 24-5-2016. Edited.
