Leukaemia Classification - Common, Rare and More

Leukaemia is a complex and devastating blood cancer that originates in the bone marrow. It occurs when abnormal white blood cells multiply rapidly and uncontrollably, specifically the leukocytes responsible for defending the body against infections and diseases.

As these malignant cells multiply, they disrupt the production and function of normal blood cells, leading to various symptoms and complications. Leukaemia impairs the body's ability to fight infections, transport oxygen, and control bleeding.

Early detection and classification of leukaemia and accurate diagnosis are crucial for timely intervention and effective treatment strategies to improve patient outcomes and enhance their quality of life.

Leukaemia occurs with an abnormal mutation (changes) in the DNA of the new blood cells, and further multiplication of these mutated cells happens. It is vital to understand the causes of the disease to determine the correct leukaemia classification. It can be influenced by various risk factors contributing to this disease's development.

Meanwhile, the exact cause behind the mutation of the DNA is still under review. 

The bone marrow typically produces different types of blood cells, including red blood cells (RBCs), white blood cells (WBCs), and Platelets.

Risk Factors of Leukaemia

In addition to a family history of blood cancers, other risk factors can increase the chances of developing leukaemia. One should be aware of the classification of leukaemia and these risk factors to choose the best line of treatment.

1. Smoking: Engaging in first or second-hand tobacco smoking is a well-known risk factor for leukaemia.

2. Exposure to Certain Industrial Chemicals: Formaldehyde and benzene are common industrial chemicals that can elevate the risk of leukaemia when individuals are exposed to them for extended periods.

3. History of Cancer Treatment: Those who have undergone radiation or chemotherapy for cancer have an increased risk of developing leukaemia. 

4. Genetic Disorders: Certain genetic disorders, such as Down syndrome and Klinefelter syndrome, may be a risk factor for leukaemia.

5. Other Forms of Blood Cancers: A previous history of blood cancer may increase your risk of developing leukaemia.

Note: It is crucial to understand that the existence of these risk factors does not ensure the development of leukaemia. However, these factors do impact the leukaemia classification to an extent.

It is recommended to speak with a healthcare practitioner who can provide individualised advice and direction if there are worries about the possibility of getting leukaemia.

Understanding the classification of leukaemia is integral to deciding the best course of action. Leukaemia can be classified into two types based on how quickly it develops or worsens: acute and chronic. Below is a detailed look at both of them:

1. Acute Leukaemia: This form is a rapidly progressing form of the disease and tends to show symptoms within a few weeks of leukaemia cell formation. It leads to the buildup of immature and non-functional blood cells in the bone marrow. Most commonly, it occurs in children.

2. Chronic Leukaemia: This type progresses slowly and is relatively more common in adults than children. The symptoms may not show up for years. It causes the accumulation of relatively mature but still abnormal blood cells. However, the slower growth rate of chronic leukaemia can make it more challenging to treat effectively.

Each leukaemia classification has its characteristics and affects different age groups. Some varieties grow quickly and require immediate treatment, while others progress slowly, and treatment may take time to complete.

There are four main types of chronic and acute leukaemia classification include:

1. Acute Lymphoblastic Leukaemia (ALL): ALL is commonly found in children and teenagers but may also occur in adults. It leads to the development of many lymphocytes.

   The disease progression rate is higher because it is acute but may be easier to treat than the chronic forms.

2. Acute Myelogenous Leukaemia (AML): The type of cancer known as acute myeloid leukaemia is the most common type in adults. It develops when immature white blood cells, called myeloid blasts, grow uncontrollably.
   A quite aggressive form of cancer because of its faster progression, it requires urgent attention.

3. Chronic Lymphocytic Leukaemia (CLL): CLL occurs when there is an outburst of development of white blood cells called lymphocytes. It mainly affects individuals between older adults and is rare in children.
   CLL generally grows gradually and may now show symptoms until it reaches later stages. Doctors usually monitor the disease and initiate treatment only if symptoms develop.

4. Chronic myelogenous leukaemia (CML): CML is often caused by an abnormal number of unhealthy white blood cells.

   More common in middle-aged adults, it is rare in children. CML progresses slowly and has different phases.

Leukaemia comes in distinctive forms, some less prevalent than others. The most crucial leukaemia classification for the rare types includes the following:

1. Prolymphocytic Leukaemia (PLL): This type of cancer can develop when there is an out-of-control growth of white blood cells. Generally affects older adults, the symptoms of PLL may be similar to other types of leukaemia, such as flu-like symptoms, easy bruising, and unexplained weight loss.

2. Large Granular Lymphocytic (LGL) Leukaemia: A chronic form of leukaemia in which the body produces abnormally large lymphocytes. When diagnosed with LGL leukaemia, patients usually experience flu-like symptoms, frequent infections, and unexplained weight loss.

3. Hairy Cell Leukaemia (HCL): A rare type of chronic leukaemia that begins in the bone marrow. As the name suggests, the leukaemia cells, when seen through a microscope, appear as thin hair-like projections. It mainly affects adult men, with very few cases reported in young children.

4. Myelodysplastic Syndromes (MDS): A category of disorders characterised by dysfunction in the bone marrow, which produces blood cells. This results in a deficiency of blood cells, including platelets, white blood cells, red blood cells, or occasionally all three.

5. Myeloproliferative Neoplasms (MPNs): A group of blood disorders in which the bone marrow produces excessive specific blood cells - WBC, RBC, or platelets.
   There are six types of MPNs, each characterised by which specific blood cells are affected:

   1. Chronic Eosinophilic Leukaemia: In this type, there is an overproduction of eosinophils, which are a type of white blood cell that helps fight allergies.
      
      
   2. Chronic Myelogenous Leukaemia: Occurs when there are excess white blood cells in the bone marrow.
      
      
   3. Chronic Neutrophilic Leukaemia: There is an abnormal increase in neutrophils, which are white blood cells responsible for fighting infections.
      
      
   4. Essential Thrombocythemia: This condition results in a higher number of platelets formation.
      
      
   5. Polycythemia Vera: A higher production of red blood cells than normal causes this condition.
      
      
   A person's specific type of MPN determines the symptoms they experience, available treatment options, and overall prognosis.

6. Adult T-cell Leukaemia/Lymphoma (ATLL): A rare form of leukaemia classification that affects a subset of white blood cells known as T-cells. The epidermis, lymph nodes, blood, and other body regions may contain it. There are four types of ATLL:

   1. Acute: This type develops rapidly and includes symptoms like fatigue, skin rash, and enlarged lymph nodes in the neck, underarms, or groyne.
      
      
   2. Lymphomatous: This type primarily affects the lymph nodes but can also cause high levels of white blood cells.
      
      
   3. Chronic: This type grows slowly and leads to increased lymphocytes in the blood, enlarged lymph nodes, skin rash, or fatigue.
      
      
   4. Smouldering: This type grows slowly and has mild symptoms, such as a few skin lesions.
      
      To diagnose ATLL, doctors may need to take a small tumour or abnormal skin tissue sample called a biopsy and examine the cells under a microscope.

Leukaemia diagnosis and treatment require a thorough and multidisciplinary approach. Here are the aspects involved in the diagnosis of the disease based on the classification of leukaemia:

1. Medical History and Physical Examination: The healthcare provider will gather information about symptoms and medical history and conduct a thorough physical examination.

2. Blood Tests: Blood samples will be taken to analyse the complete blood count (CBC) and identify abnormal blood cells or other irregularities.

3. Bone Marrow Aspiration and Biopsy: A small sample of bone marrow and a small piece of bone is obtained to examine the cells and determine the presence of leukaemia.

4. Cytogenetic Analysis: Genetic testing is performed to identify specific chromosomal abnormalities associated with different types of leukaemia.

5. Lumbar Puncture: In certain cases, a sample of cerebrospinal fluid is collected through a lumbar puncture to check for leukaemia cells in the central nervous system.

Once diagnosed, treatment strategies are tailored as per the individual's leukaemia classification, overall health, and other factors. Below are some of the most crucial treatment options:

1. Chemotherapy: Anti-cancer drugs are administered orally, intravenously, or directly into the spinal fluid to kill leukaemia cells throughout the body.

2. Radiation Therapy: High-energy X-rays or other forms of radiation are used to target and destroy leukaemia cells.

3. Stem Cell Transplant: Healthy stem cells are introduced into the body to replace damaged or destroyed bone marrow cells after high-dose chemotherapy or radiation.

4. Targeted Therapy: Drugs are used to specifically target certain molecules or genes that are involved in leukaemia cell growth.

5. Immunotherapy: This treatment stimulates the immune system to recognise and attack leukaemia cells. 

6. Clinical Trials: Participation in clinical trials provides access to innovative treatments tested for their effectiveness against leukaemia.

Untreated leukaemia can lead to significant risks and complications, highlighting the importance of prompt diagnosis and treatment. Some of the potential consequences of untreated leukaemia include:

1. Anaemia and Bleeding: The regular production of platelets and red blood cells is disrupted by leukaemia. Anaemia symptoms, including weakness, exhaustion, and shortness of breath, can result from untreated leukaemia. Additionally, a low platelet count can reduce the bleeding process.

2. Organ Dysfunction: As leukaemia cells accumulate, they can infiltrate the liver, spleen, lymph nodes, and central nervous system. This infiltration can impair organ function, causing symptoms such as abdominal pain, enlargement of organs, neurological abnormalities, and breathing difficulties.

3. Increased Infection Susceptibility: As leukaemia weakens the immune system, people are more susceptible to infections. Without proper care, the compromised immune system can lead to frequent and severe infections that can be fatal.

4. Blood Clotting Abnormalities: Certain classifications of leukaemia can disrupt the body's natural clotting mechanisms, increasing the risk of abnormal blood clot formation. This can lead to deep vein thrombosis, pulmonary embolism, or other thrombotic events, which can be life-threatening. 

5. Disease Progression: Without treatment, leukaemia is a progressive condition that can get worse over time. Leukaemia cells can invade different organs and tissues and proliferate abnormally, causing additional harm and complications.

For anyone who faces any abnormal symptoms, including the aforementioned or has concerns about their health, scheduling an appointment with a healthcare professional is recommended.

A doctor can evaluate your symptoms, perform necessary tests, and provide appropriate guidance or referrals if leukaemia or any other condition is suspected. They can also help you understand the leukaemia classification and choose the best course of action. 

Early detection and timely treatment can significantly improve outcomes for leukaemia and other types of cancer. While these symptoms can vary depending on the type of leukaemia, some common signs to watch out for include:

1. Unexplained Fatigue or Weakness: Feeling excessively tired or weak, even with adequate rest, could be a symptom of leukaemia.

2. Frequent Infections: Recurrent infections, such as frequent fevers, sore throat, or pneumonia, may indicate a weakened immune system, a sign of leukaemia.

3. Bone or Joint Pain: Persistent bone or joint pain, often described as deep or aching, may occur in some cases of leukaemia.

4. Unexplained Weight Loss: Significant and unexplained weight loss without any diet or physical activity changes could be a cause of concern.

5. Excessive Sweating: Night sweats that are severe and recurrent, leading to soaking the bedclothes, can be a symptom of certain types of leukaemia.

6. Easy Bruising or Bleeding: Unusual bruisings or bleeding, such as frequent nosebleeds, bleeding gums, or prolonged bleeding from cuts, may be indicative of a health condition.

7. Enlarged Lymph Nodes or Swelling: Leukaemia can cause swelling or enlargement of lymph nodes, often in the neck, armpit, or groyne areas.

Understanding the classification of leukaemia is crucial in diagnosing, treating, and managing this complex group of blood cancers. Each type has unique characteristics, including the affected cells and progression patterns.

Awareness of leukaemia classification and types empowers patients and their families to participate in their treatment journey and make informed decisions actively. Turn to HexaHealth, where our seasoned experts can assist you in understanding the treatment and diagnosis of leukaemia in detail. Reach out to us and learn more today!

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