Blood Test for Leukemia

What is leukemia?

The term leukemia is made from two words: “white” (leukos) and “blood” (haima). 

Leukemia is a form of cancer that affects the blood-forming tissues of the body, including the bone marrow as well as the lymphatic system. 

By definition, leukemia is the rapid proliferation of dysfunctional white blood cells that accumulate in the blood and bone marrow, impeding the production of proper blood cells. Thus an individual with leukemia will lack normal red blood cells, platelets, and functional white blood cells. This can cause fatigue, infections, easy bruising or bleeding, and many other complications.

Leukemia does not form a mass (tumor) that can be seen in imaging tests like X-rays, or CT scans. Many types of leukemia occur. Some affect children, while others are more common in adults. Therefore, a blood test for leukemia in adults and children may be suggested depending on if it is acute or chronic, and most importantly, according to which blood cells are implicated.

Can leukemia develop suddenly?

In certain instances, leukemia can develop suddenly, especially in the case of acute leukemia. The symptoms of acute leukemia are visible in days/weeks and can mimic the flu with fever, malaise, and easy bruising/bleeding, so possibly requiring emergency evaluation. 

Chronic leukemia, on the other hand, develops over months/years and can show little or no symptoms initially. It is diagnosed as an incidental finding during a blood test during a physical exam. 

Leukemia originates when DNA mutates in a stem cell in the bone marrow and subsequently alters the blood cell formation process. Blood cells pass through many stages before reaching the maturation stage. Mature, normal blood cells include:

• Red blood cells transport oxygen from the lungs to all tissues and other organs throughout the body. They also help carry carbon dioxide, a waste product back to the lungs for exhalation. In this way, they play a crucial role in delivering other essential nutrients and materials to cells as required for the proper functioning of the body. 
• White blood cells are also known as leukocytes, and are essential components that are protected against infection and diseases. White blood cells are of several types like neutrophils, lymphocytes, eosinophils, and basophils that circulate in the bloodstream and tissues. Further, they identify, attack, and destroy harmful invaders such as bacteria, viruses, fungi, and parasites, acting as a body’s defense force. 
• Platelets: Also known as thrombocytes, platelets are small cell fragments in your blood that help in stopping bleeding and forming blood clots. 

When blood cells develop normally, they mature into specified forms. They are categorized as:

• Myeloid cells are derived from myeloid progenitor cells in the bone marrow. They include granulocytes like neutrophils, basophils, and eosinophils, monocytes, erythrocytes (red blood cells), and platelets (via megakaryocytes). 
• Lymphoid cells are derived from lymphoid progenitor cells in the bone marrow and thymus. They include T cells, B cells, and natural killer (NK) cells.

A doctor suggests a blood test for leukemia to detect abnormal blood cell counts and to identify immature or abnormal cells. 

Since leukemia disrupts the normal function and production of blood cells, a blood test can help reveal high white blood cell counts, low red blood cells or platelet counts, and leukemia cells. It is crucial to diagnose the disease and guide further evaluation and treatment. 

How does leukemia affect your body?

It disrupts the normal blood cell production in the bone marrow. Abnormal white blood cells grow out of control and invade normal red blood cells, white blood cells, and platelets. This leads to several problems: 

1. Reduced healthy blood cells can cause anemia resulting in fatigue, weakness, or shortness of breath. Additionally, it may cause low platelet count that leads to easy bruising, bleeding, petechiae, nose bleeds, and bleeding gums. Low or abnormal white blood cells weaken the immune system and increase the risk of severe infections. 
2. Other effects may include bone pain or tenderness, swollen lymph nodes, liver or spleen, weight loss, fever, or night sweats. 

What are different types of leukemia?

The classification of leukemia depends on how fast the disease spreads and its severity and whether leukemia cells arise from myeloid cells or lymphoid cells.

Below are the primary types of leukemia:

1. Acute lymphocytic leukemia (ALL) is also known as lymphoblastic leukemia. This cancer type begins in the bone marrow. It affects lymphoid cells, specifically immature lymphocytes ( a type of white blood cell) that overproduce rapidly and can crowd out normal blood cells in the bone marrow.

• Cell type: It is the lymphoid cells (lymphocytes mainly B or T cells). These cells are crucial for the immune system, but in ALL, they become cancerous and do not function properly.
• Progression: The term “acute” suggests the disease is fast progressing. In acute lymphoblastic leukemia (ALL), the growth of lymphoblasts is rapid, ultimately replacing normal blood-forming cells within the bone marrow at a high volume and capacity. Further, this greatly impacts the marrow's function to produce enough healthy red blood cells (RBCs), white blood cells (WBCs), and platelets. 
• Who does it affect: ALL is the leading pediatric cancer, especially those under age 5, and can affect teens and young adults up to the age 39, with a high chance of getting treated, if detected in time. A healthcare professional suggests a blood test for leukemia in child depending on the symptoms such as fatigue, infections, bleeding, or bruising. Additionally, acute lymphocytic leukemia occurs less in adults. Compared to children, the probability of receiving favorable treatment outcomes is less in adults. 

2. Acute Myeloid Leukemia (AML): This cancer type starts in the bone marrow and leads to rapid and uncontrolled growth of abnormal myeloid cells. These cells are precursors to several types of blood cells, including granulocytes & monocytes (both types of white blood cells) and platelets. 

• Cell Type: Leukemia affects a variety of myeloid cells, specifically, myeloblasts, which are essentially immature myeloid cells. These abnormal cells crowd-out healthy normal blood-forming cells in the bone marrow, leading to a shortage of normal red blood cells, white blood cells, and platelets. 
• Progression: AML is an acute disease, meaning it develops quickly. If it does not get treated in a timely manner, AML can be fatal within weeks or months due to rapid accumulation of abnormal cells (leukemia) and the resulting failure of normal blood cell production. 
• Who does it affect: Acute myeloid leukemia is very common in adults, especially those over the age of 60. Therefore, a doctor is more likely to suggest a blood test for leukemia in adults. Common symptoms include fatigue, bone pain, joint pain, frequent infections, and easy bruising or bleeding. 

3. Chronic Lymphocytic Leukemia (CLL) affects the blood and bone marrow, specifically involving abnormal growth of white blood cells, called lymphocytes, mainly B cells. In CLL, the bone marrow produces too many lymphocytes in the blood, bone marrow, lymph nodes, and sometimes liver and spleen. The abnormal lymphocytes resemble normal lymphocytes but do not function properly, especially in fighting infections. 

• Cell involved: CLL mainly affects lymphoid cells, specifically B lymphocytes. These are types of white blood cells that usually help the body fight infection. In CLL, the B lymphocytes become cancerous and do not function properly. 
• Progression: CLL is called chronic because it often progresses slowly over time. Some patients with CLL do not have symptoms for years, and the disease may be discovered during a routine blood test for leukemia detection. 

Further, the abnormal cells multiply slowly over time, crowding out the healthy blood cells and potentially leading to complications from anemia, infections, or easy bleeding. 

• Who does it affect: CLL is the most common chronic leukemia in adults over 65 and is most frequently diagnosed in older individuals. It is rare in children. 

4. Chronic Myeloid Leukemia (CML) also known as chronic myelogenous leukemia, is a type of blood cancer that occurs in the bone marrow and primarily affects myeloid cells, especially granulocytes (A type of white blood cells). 

• Cell involved: CML involves excessive proliferation of abnormal myeloid cells (mostly granulocytes) in the bone marrow. These cells multiply uncontrollably and can replace healthy blood cells, leading to a variety of symptoms. 
• Progression: CML is chronic because it progresses slowly. The disease often begins with a chronic phase that is mild but can transform into more aggressive forms if left untreated. 
• Who does it affect: CML can occur at any age, but it mainly affects adults over 65.. CML is not an inherited disease and is not present at birth; the Philadelphia chromosome occurs immediately in a blood-forming stem cell.

What are chances of getting leukemia?

Leukemia is a smaller percentage of cancers in India but it is not among the most common cancers overall. Cancer incidence in India is rising, with an estimated 1.46 million new cancer cases in 2022, and approx. 1.57 million in 2025.

Leukemia can affect people of all ages, but it is more common among people who:

• Age 65 to 74. 
• Male
• “Caucasian” or “White” refers to a racial/ethnic group typically traced to origins in Europe, the Middle East, or North Africa.

Leukemia is the most common type of cancer in children and is the leading form of cancer among both sexes. For all ages, leukemia is among the most frequent malignancies when analyzed by type, but cancers like lung and breast cancer are more prevalent overall in adults. 

Symptoms and Causes

What are the symptoms of leukemia?

You may or may not develop noticeable symptoms in the early stages depending on, in part, on the type of leukemia. Some common symptoms include:

• Fatigue
• Fever or night sweats
• Frequent infections
• Shortness of breath
• Pale skin
• Unexpected weight loss
• bone/joint pan
• Pain under your ribs on the left side
• Swollen lymph nodes in your stomach, underarm, and neck. You may also experience an enlarged spleen or liver. 
• Nosebleeds, bleeding gums. Petechiae (tiny red spots in the skin)

Causes of Leukemia

Leukemia begins when the single cell DNA in your bone marrow changes. DNA is the “instruction code” that tells a cell when to grow, how to grow, and when to die due to mutation, or coding error, leukemia cells keeps multiplying, 

Researchers believe several factors are known to increase the risk of developing leukemia. These risk factors can be genetic, lifestyle, and environmental factors. Most importantly, people with known risks do not develop leukemia, and many individuals with leukemia have no identifiable risk factors. 

Category	Examples
Genetic/inherited Factors	Down syndrome, Fanconi anaemia, family history
Environmental/Chemical Factors	Radiation, Benzene, Formaldehyde, Agent Orange, Pesticides.
Previous Cancer Therapy	Chemotherapy/radiation therapy
Lifestyle	Smoking, drinking, obesity
Infections/other	HTLV-1, EBV, chronic food disorders

Is there a group of people who are more likely to get leukemia than others?

Yes, certain people are at a higher risk of developing leukemia. Those with increased risk include individuals exposed to high levels of radiation or certain chemicals (like benzene), smokers, people with a history of radiation therapy or chemotherapy, and those with rare genetic syndromes such as Down syndrome, neurofibromatosis, Klinefelter syndrome, Schwachman-Diamond syndrome, Fanconi anemia, or Bloom syndrome. 

Advancing age, being male, and having a family history of leukemia can also raise the risk. However, most people with these risk factors do not develop leukemia, and many who do have no known risk factors.

Diagnosis and Tests 

How is leukaemia diagnosed?

Leukemia is diagnosed through a series of steps and tests, typically beginning with a medical examination and followed by specialized laboratory procedures. 

1. Physical exam: First, your healthcare provider will review your symptoms, then, your medical history, followed by a physical exam to look for signs such as pale skin, swollen lymph nodes, or an enlarged liver or spleen. 
2. Complete blood count (CBC): A CBC test is often part of a blood test for leukemia detection to help measure the number and types of blood cells. It can also help detect abnormal levels that suggest leukemia. 
3. Blood cell examination: This specialized laboratory test includes flow cytometry and peripheral blood smear tests. 

• Flow cytometry uses lasers to identify and count specific cells, helping to classify leukemia. 
• A blood smear or peripheral blood smear involves a drop of blood spread on a slide and examined under a microscope. This can show abnormal cell shapes or immature (blast cells) that resemble leukemia. 

1. Bone marrow biopsy and aspiration involve a sample of bone marrow, usually from the hipbone to examine the cell for leukemia and determine its types. 
2. Imaging and other tests: Apart from a blood test for leukemia detection, bone marrow biopsy, and blood cell examination, your healthcare provider may order a chest X-ray. CT scan, or magnetic bones, organs, or tissue. These imaging tests may be used to detect leukemia spread to other organs. 
3. Lumbar puncture: A sample of your spinal fluid is taken to check if the leukemia has spread to the central nervous system (CNS), since the leukemia sometimes can involve the brain and spinal cord. 

What do leukemia test results reveal?

A blood test for leukemia results may indicate:

Abnormal white blood cell (WBC) count

A high white blood cell count, leukocytosis, is a common finding in leukemia. It occurs when the count exceeds 11,000 microliter. Elevated counts can also occur due to infections or other conditions. 

On the other hand, some people with leukemia may experience a low white blood cell count, or leukopenia that can crowd out normal blood cells in the bone marrow. Both these findings are crucial indicators of leukemia and are usually evaluated with other white blood cell counts and clinical findings. 

Management and Treatment

What is the treatment for leukemia?

Leukeia is treated depending on the type of leukemia you have, your age, and overall health. Common treatments for leukemia include the following: 

• Chemotherapy is the most common treatment for leukaemia. This treatment involves medications to kill leukaemia cells and prevent them from growing. Additionally, it can be given orally, by injection, or intravenously. 
• Targeted therapy: As the name suggests, these drugs target specific abnormalities in leukaemia cells, such as certain proteins or gene mutations, to block their growth and survival. 
• Radiation therapy involves the use of high-energy rays to kill cancer cells or prevent them from growing. 
• Bone marrow transplant: In this procedure, the diseased bone marrow is replaced with healthy stem cells, which can come from you (the patient) or a donor. 
• Immunotherapy: This system helps the immune system fight leukaemia cells.
• Chimeric antigen receptor (CAR) T cell therapy is a type of immunotherapy whichre T cells are genetically engineered tmore effectivelyer target and destroy cancer cells. 

What are the phases of leukemia treatment?

There are three phases of leukemia treatment: Induction therapy, Consolidation or Intensification, and Maintenance therapy. 

Induction Therapy

Induction therapy helps kill as many leukemia cells and obtain remission. Remission means that the blood and bone marrow are free of leukemia cells and the body is producing normal blood cells. 

Induction therapy lasts about a month and is started as soon as possible from the time of diagnosis. It is successful if it achieves remission (leukemia cells are less than 5% in the bone marrow) and normal blood cell counts.

Consolidation/Intensification

Once you have received remission, consolidation or intensification aims to destroy any remaining leukemia cells that may not be detectable through standard tests but could relapse. Using consolidating remission it may be possible to limit or avoid having leukemia relapse. 

Additionally, consolidation therapy usually lasts a few months; however, the exact length of time depends on the protocol and individual risk factors. Healthcare professionals may order a stem cell transplantation as a part of consolidation for higher-risk patients. 

Maintenance Therapy 

Maintenance therapy keeps leukemia in remission by killing any remaining leukemia cells that might regrow and cause relapse. This therapy is useful for ALL. 

Additionally, maintenance therapy usually lasts approximately two years for ALL, including the time spent in this phase. Regular blood tests and clinic visits are suggested for close monitoring. 

Note: Healthcare providers may modify your treatment for leukemia if needed. 

Outlook/Prognosis

What can you expect from your leukemia diagnosis?

If you are diagnosed with leukemia, your outcomes depend on several factors, including the specific type of leukemia, your age, overall health, and how well the cancer responds to treatment. 

1. Genetic abnormalities or mutations aid in determining the prognosis and treatment outcome for patients with leukemia, particularly in AML. 
2. Type of leukemia is a key factor in determining prognosis and treatment response. Certain types of leukemia offer more successful results than others, and survival rates vary significantly between subtypes. 

Types of Cancer	Survival Rates
1. Chronic lymphocytic leukemia (CLL)	5-year (about 88-88.5%)
2. Chronic myeloid leukemia (CML)	5 years (about 70%)
3. Acute lymphocytic leukemia (ALL)	Approx. 71-72% overall, but can exceed 90% in children under 20.
4. Acute myeloid leukemia (AML)	Approx. 5 years (About 31–32% overall, but higher in younger patients (up to 69% in those under 20)
5. Chronic Myelomonocytic leukemia (CMML)	Poorer prognosis (10-20%)

1. Blood cell counts at the time of diagnosis such as higher-than-normal white blood cells (WBCs), low red blood cells or hemoglobin, or thrombocytopenia (low platelet count) are also crucial for both identifying the disease and understanding its severity. 
2. Age is a powerful predictive indicator of outcome in leukemia. Children and adolescents tend to have much better survival rates and outcomes than older adults. 
3. Health: Younger age and better overall health at diagnosis typically lead to improved leukemia outcomes. When young and healthy, you can tolerate intensive treatments better and have high survival rates. 
4. Response to treatment is also one of the crucial factors in leukemia prognosis. Achieving complete remission quickly means leukemia cells are no longer detectable in the bone marrow after the first chemotherapy, showing better outcomes

7.The presence of leukemia cells in your central nervous system is serious and linked to a significantly worse prognosis. The involvement of CNS makes the treatment more complicated, often leading to lower survival rates. 

Hence, there is no need to delay getting a blood test for leukemia detection done. Early diagnosis of leukemia improves prognosis, so prompt testing is crucial if you are facing unexplained fatigue, weight loss, frequent infections, or easy bruising. 

What is the survival rate of leukemia?

The survival of leukemia depends on the specific type and age group, but overall, recent statistics show: 

Types of Leukemia	5 Year Survival Rate	Number of deaths per 100, 000 persons	Age bracket with the highest death rate
Acute Lymphocytic Leukemia (ALL)	67-70%	Males: 0.5 per 100, 000 Females: 0.3 per 100, 000	65-84
Acute Myeloid Leukemia (AML)	31.7%	Males: 3.4 per 100, 000 Females: 2.1 per 100, 000	65+
Chronic Lymphocytic Leukemia (CLL)	88.0%	Males: 1.6 per 100, 000 Females: 0.7 per 100, 000	75+
Chronic Myelogenous Leukemia (CML)	70.6%	Males: 0.4 per 100, 000 Females: 0.2 per 100, 000	75+

Is leukemia curable?

When a disease is cured, it means it won’t come back and no further treatment is needed. Early diagnosis can help a healthcare provider suggest the most appropriate treatment, almost eliminating the chances of relapse. 

Certain types of leukemia such as acute lymphoblastic leukemia (ALL) is considered curable in children with long-term survival rates exceeding 90% in many cases. Chronic myeloid leukemia (CML) is also considered highly treatable, and with modern targeted therapies, you can achieve long-term remission and nearly normal life expectancy. 

Not every leukemia can be cured. Treatment outcomes depend upon the specific type of leukemia, your age, overall health, and effectiveness of treatment. Often younger patients with favorable conditions can be cured, others may experience long-term remission or require ongoing management. 

Living With 

What questions should you ask your doctor?

Do not feel shy to ask your doubts to your healthcare provider. The more you ask, the more you will have clarity about your health condition with leukemia and get appropriate suggestions. 

Questions you may ask: 

• What is your leukemia type, and which blood cells are affected?
• What specific leukemia type do you have and how fast does it grow?
• How early was your leukemia diagnosed?
• What treatment options suit the best?
• What are the advantages and disadvantages of treatment for leukemia? How can you reduce side effects of the treatment?
• Why do you need a blood test for leukemia detection?
• Which treatment plan is more effective, and why?
• When should you start treatment, how long will each stage take?
• How long will the overall treatment take, and what is the duration of each stage?
• How long will you need to stay in the hospital?
• Can you expect parenthood, how can you preserve your fertility?
• What are the expected success and survival rates for your type of leukemia?
• How reliable is a blood test for leukemia in adults and children?

A Note from Redcliffe Labs

If a blood test suggests leukemia additional specific testing such as bone marrow biopsy or flow cytometry is required to confirm the diagnosis of leukemia and its type. Consult your doctor to understand the blood test for leukemia results crucial for a personalized care plan. 

Redcliffe Labs is committed to providing accurate, reliable, and timely diagnostic services to support your health and wellness journey. Our comprehensive range of tests, including full body checkups, specialized blood tests, and cancer screenings is designed to help detect health issues early and empower you with actionable insights. 

With our user-friendly mobile app and doorstep sample collection, you can book a blood test for leukemia in adults and children at your convenience and access your reports online.