Leukaemia is a haematological malignancy (type of blood cancer) that typically starts in the bone marrow. An abnormal rise in underdeveloped white blood cells termed ‘blasts’ or ‘leukaemia cells’ results in leukaemia. After a while, normal blood cells die and are replaced by these abnormal cells created in the bone marrow that do not die and divide uncontrollably.
In later stages, these leukaemic cells tend to accumulate in various organs like bone marrow, spleen and other organs and affect their functioning.
Depending on the growth rate, leukaemias can be classified into acute (fast-growing) leukaemia and chronic (slow-growing) leukaemia.
In the case of chronic leukaemia, the symptoms start to appear in the later stages and therefore, this type of leukaemia is a lot more challenging to treat when compared to acute leukaemia.
- 1. Acute Lymphocytic Leukaemia (ALL): Acute lymphocytic leukaemia happens when there is a mutation in blood-producing cells present in the bone marrow. This leads to the overproduction of immature white blood cells, called leukaemic blasts or lymphoblasts. As this condition affects the bone marrow’s ability to produce normal white blood cells and red blood cells, the incidence of anaemia and recurrent infections become more common among ALL patients. Acute Lymphocytic Leukaemia (ALL) that specifically arises from T-lymphocytes is called T-Cell Acute Lymphoblastic Leukaemia (T-ALL).
- 2. Acute Myeloblastic Leukaemia (AML): AML arises from the myeloid cells present in the bone marrow. Myeloid cells refer to those cells that can give rise to red blood cells, white blood cells (except lymphocytes) and platelets. As this condition affects the production of red blood cells and platelets, AML can lead to anaemia, easy bleeding and bruising.
- 3. Chronic Lymphocytic Leukemia (CLL): Chronic lymphocytic leukaemia happens when the production of white blood cells (called lymphocytes) in the bone marrow is affected, and this cancer type progresses slowly. The cancer type is more common among older adults.
- 4. Chronic Myeloid Leukaemia (CML): Also known as granulocytic leukaemia, this is a cancer type wherein myeloid cells start growing abnormally.
- 5. Hairy Cell Leukaemia: This is a slow-growing cancer type that develops from the bone marrow and leads to the production of an abnormally high number of B-cells (B-lymphocytes), which are responsible for fighting various infections. Also, it is one of the rare-occurring cancers.
The symptoms of leukaemia are often vague and are often similar to that of less severe health conditions, and this is one of the reasons they are often ignored. This leads to delayed diagnosis, which in turn leads to poor clinical outcomes.
- Recurring infections
- Poor blood clotting
- Easy bruising and bleeding
- Nosebleeds and bleeding gums
- The appearance of tiny red spots on the skin (petechiae)
- Swollen lymph nodes in the regions of neck, underarm, stomach and groin
- Unintentional weight loss
- Profuse sweating during the night
- Pain under the ribs, especially on the left side
- Shortness of breath
- Pain in the bones and joints
However, as discussed earlier, the chronic form of leukaemia may not show any symptoms in the early stages; however, they become apparent as the disease progresses.
Researchers have identified a few factors that increase the risk of leukaemia:
- Age: Chronic leukaemias are more common among elders; acute lymphoblastic leukaemia, on the other hand, is more common among children.
- Smoking: The incidence of acute myeloid leukaemia (AML) is found to be more prevalent among smokers.
- Radiation Exposure: Radiation exposure can increase one’s risk of developing acute lymphoblastic leukaemia (ALL), acute myeloid leukaemia (AML) and chronic myeloid leukaemia (CML). Those who have received radiation therapy for other cancers are at a higher risk of developing leukaemia.
- Exposure to Certain Chemicals: Exposure to certain chemicals like pesticides and industrial solvents can increase the risk of leukaemia.
- Chemotherapy in the Past: Certain chemo drugs can increase one’s risk of developing acute leukaemias in later years.
- Rare Congenital Diseases and Certain Blood Disorders: Those with certain congenital diseases are at a higher risk of developing ALL and AML. For instance, individuals diagnosed with Down syndrome, Bloom syndrome and ataxia-telangiectasia have an increased risk of being diagnosed with acute leukaemias. Certain blood disorders are also found to increase the risk of developing AML.
- Certain Infections: HTLV-1 (human T-lymphotropic virus) infection is found to increase T-cell leukaemia risk.
- Family History: Those with a family history of leukaemias are at an increased risk of developing this disease.
- Gender: Studies have found that leukaemias are more common among men than women.
If an individual is suspected to have leukaemia, the following tests are recommended by the doctor:
a. Physical Exam and Medical History Assessment: If an individual is experiencing the symptoms of leukaemia, the doctor assesses the medical history to understand the cause behind the symptoms. He/she may also conduct a quick physical examination to check for any swollen lymph nodes, pale skin caused due to anaemia, etc.
b. Blood Tests: If leukaemia is suspected, one of the first things that the doctor recommends is a blood test. If a blood test reveals a high number of abnormal white blood cells and a low number of normal white blood cells, red blood cells, or platelets, leukaemia is suspected.
c. Cytogenetic Analysis: The presence of abnormal chromosomes is a sign of leukaemia. To achieve an accurate diagnosis, the doctor may recommend a cytogenetic analysis, wherein the cells present in the samples of blood, bone marrow or lymph nodes are collected and examined for abnormalities in chromosomes, including damaged, missing, distorted or extra chromosomes.
d. Bone Marrow Biopsy: During bone marrow biopsy, a syringe will be used to extract a little amount of fluid from the bone marrow. The doctor may also consider extracting a small core of bone marrow as well. These samples are later examined under the microscope. They’ll also be tested for gene changes that could be crucial in identifying and tracking the disease.
e. Lymph Node Biopsy: If enlarged lymph nodes are found, the doctor may recommend a lymph node biopsy. This test will assist the doctor in determining whether or not the patient has leukaemia. The procedure involves extracting tissue from the concerned lymph node and examining it under a microscope.
f. Lumbar Puncture (Spinal Tap): A lumbar puncture or a spinal tap is a medical procedure wherein the cerebrospinal fluid is extracted and examined in order to check if leukaemia has spread to the brain and spinal cord. A fine needle will be inserted into the space between bones in the lower back in order to collect the fluid around the spine. This sample will be examined under a microscope for the presence of leukaemia cells.
g. Chest X-ray: At times, the doctor may also recommend an X-ray scan in order to check for swollen lymph nodes in the chest region.
i. Imaging Tests: Imaging tests like MRI scan, PET CT scan or ultrasound scan may be recommended to check if the disease has spread to other organs.
Upon receiving a confirmed diagnosis, haemato-oncologists carefully assess the patient’s overall condition and a few other factors, namely the stage of the disease, age of the patient and his/her overall condition before devising a personalised treatment plan.
a. Chemotherapy: Chemotherapy is the most commonly recommended treatment option for leukaemia. As a systemic therapy, chemotherapy destroys leukaemia cells that are present throughout the body. Chemotherapy uses highly potent anticancer drugs to kill the leukaemia cells. In most cases, more than one chemo drug is used for better treatment response.
Usually, chemotherapy may be administered in cycles with a specified number of days of treatment followed by days of rest – this is important for the body to recuperate and respond well to the treatment. Treatment duration varies from patient to patient depending on the severity of the disease and the overall condition of the patient.
b. Radiation Therapy: Radiation therapy uses high-energy radiation beams, which could be X-ray or proton beams, to kill or stop leukaemia cells from growing and dividing. Radiation beams can be delivered to specific locations in the body where cancer cells have accumulated (like spleen, lymph nodes, etc.), or it can be the whole-body treatment given prior to stem cell transplantation.
c. Stem Cell Transplantation/ Bone Marrow Transplantation: When chemotherapy or radiation therapy is administered to treat leukaemia, the bone marrow cells, which are responsible for the production of various blood cells, are damaged. In order to restore the damaged bone marrow cells, stem cell transplantation is recommended.
Stem cell transplantation or bone marrow transplantation is one of the key treatment options available for leukaemia. This procedure replaces the abnormal or cancerous cells that have been treated with high-dose chemotherapy and/or radiotherapy with new, healthy-functioning stem cells. These healthy cells could be taken from the patient (right before his/her chemotherapy or radiotherapy) or a donor’s bone marrow or blood, and transfused to the patient. These healthy stem cells will later multiply and develop into various types of blood cells, namely white blood cells, red blood cells and platelets.
d. Targeted Therapy: This treatment focuses on certain attributes seen on leukaemia cells. Targeted therapies function by preventing leukaemia cells from multiplying and dividing, cutting off the blood supply that the cells require to survive, or killing the cells directly. Targeted therapy kills only cancer cells while leaving healthy, normal cells unaffected.
e. Immunotherapy: Also known as biological therapy, immunotherapy uses specific drugs to stimulate the body’s natural defence system to attack the leukaemia cells. Immunotherapies may include interferon, interleukins and CAR-T cell therapy.
Frequently Asked Questions
1. Is leukaemia treatable?
Yes, leukaemias are treatable. Today, we have numerous treatment options available that not only increase the survival chances for the patients but also have a positive impact on the quality of life in patients.
Early detection plays a pivotal role in treating leukaemia with positive clinical outcomes. Therefore, if an individual is experiencing symptoms that are alarming and last for more than two weeks, he/she should immediately consult a doctor for further check-up.
2. Is leukaemia more common among children?
Yes, leukaemias, especially acute leukaemias, are found to be more common among children than adults. The common reasons include certain inherited syndromes that affect the immune system, certain genetic disorders and exposure to high levels of radiation, etc.
3. Can leukaemia come back?
Yes, in a few patients leukaemia can relapse or come back. Therefore, it is important for leukaemia patients to stringently stick to their follow-up regimen after the treatment.
Attending the scheduled follow-up appointments without fail helps in catching the relapses in their early stages, and treating them effectively.
4. What can I do to prevent leukaemia?
Currently, there are no known measures to prevent leukaemia among children. However, there are a few measures that you can take in order to reduce your leukaemia risk:
- a. Quit Smoking: Smoking is one of the risk factors for leukaemia among adults. Therefore quitting smoking helps in reducing leukaemia risk.
- b. Avoid Exposure to Harmful Chemicals: Certain chemicals like benzene, pesticides and industrial solvents can increase one’s risk of developing leukaemia. Therefore, it is important to avoid long-term exposure to these and other harmful chemicals.
- c. Having a Healthy Lifestyle: Having a healthy lifestyle that includes consuming a balanced diet, getting sufficient sleep and staying physically active helps in bringing down your risk of developing various cancers, including leukaemia.
Also, if you have received chemotherapy and radiation therapy in the past, please pay extra attention to any symptoms that last for more than two weeks.