Early signs of leukemia: 8 most recognizable symptoms

Leukemia is one of the most dangerous cancers because its initial signs are often vague and can easily be mistaken for the flu, anemia, or general weakness. According to estimates by international health organizations, hundreds of thousands of new cases of leukemia (blood cancer) occur worldwide each year, while many people are only diagnosed when the disease has advanced. This makes treatment more complicated and reduces the effectiveness of disease control.

If you experience persistent fatigue, unexplained fever, easy bruising, unusual bleeding, or recurring infections, these could be signs that should not be overlooked. This article will help you recognize the early signs of leukemia, understand warning symptoms, differentiate them from other common illnesses, and know when to seek medical attention for timely diagnosis and treatment. Tiptory also shares practical knowledge to help you proactively protect your health and your family's.

Part 1: Most Recognizable Symptoms of Leukemia

Symptom 1: Recognizing Leukemia Symptoms

Comparing symptoms with common cold/flu

• Many people with leukemia initially experience symptoms very similar to the flu, such as fever, fatigue, or chills, leading them to be complacent.
• If the symptoms only last a few days and then resolve on their own, and health returns to normal, it is likely a common cold/flu or viral infection.
• However, if the condition persists, recurs frequently, or worsens, you should visit a medical facility for examination and necessary blood tests to rule out leukemia and other blood disorders.

Persistent fatigue and weakness

• Feeling exhausted even after adequate rest.
• Body weakness, reduced ability to perform daily activities or work.
• This is one of the common signs of leukemia due to a decrease in the number of healthy blood cells.

Frequent nosebleeds

• Repeated nosebleeds or difficulty stopping bleeding.
• This condition may be related to a reduced platelet count, making blood clot less effectively than usual.
• If nosebleeds occur frequently without an apparent cause, you should seek medical attention early.

Recurrent infections

• Frequent sore throats, pneumonia, skin infections, or other bacterial infections.
• Prolonged or hard-to-treat infections may indicate a weakened immune system due to leukemia.

Unexplained weight loss

• Significant weight loss despite not dieting or increasing physical activity.
• Persistent weight loss is a warning sign of many serious illnesses, including leukemia.

Swollen lymph nodes

• Lymph nodes in the neck, armpits, or groin are enlarged but usually painless.
• Lymph nodes that persist for weeks or continue to enlarge should be checked by a doctor to determine the cause.

Enlarged liver or spleen

• Feeling full, uncomfortable in the upper abdomen, or getting full quickly after eating.
• This could be a sign of an enlarged liver or spleen due to the accumulation of abnormal cells.

Easy bruising and bleeding

• Bruises appearing on the skin after only minor impacts.
• Difficulty stopping bleeding from minor scratches or prolonged bleeding from small wounds.
• This is a common symptom when the platelet count is low.

Red spots on the skin

• Numerous tiny red or purple spots on the skin, often appearing on the legs, arms, or torso.
• These spots do not disappear when pressed and may be a sign of subcutaneous bleeding due to low platelets.

Excessive night sweats

• Profuse sweating during sleep even when the weather is not hot or the bedroom is cool.
• If this condition persists along with fever or weight loss, you should see a doctor to find the cause.

Bone pain or muscle cramps

• Persistent bone or joint pain or muscle cramps unrelated to injury.
• This symptom can occur when the bone marrow is affected by leukemia.

Bleeding gums

• Gums easily bleed when brushing teeth or bleeding spontaneously without an apparent cause.
• If this condition persists, especially when accompanied by bruising or nosebleeds, you should get a health check-up to detect blood disorders early.

Symptom 2: Recognizing Fatigue from Leukemia

Monitoring prolonged fatigue levels

• Prolonged fatigue is one of the early signs of leukemia but is often overlooked because many people attribute it to work stress or lack of sleep.
• If the feeling of sluggishness lasts for many days or weeks and does not improve after rest, you should proactively monitor it and seek medical attention to find the cause.

Distinguishing normal fatigue from chronic fatigue

• Normal fatigue usually diminishes after getting enough sleep or rest.
• In contrast, chronic fatigue makes you constantly feel exhausted and lacking energy even after adequate rest.
• You may also experience symptoms such as:
  • Difficulty concentrating, decreased memory.
  • Unexplained muscle aches.
  • Persistent sore throat.
  • Swollen lymph nodes.
  • Severe exhaustion lasting more than a day after light activities.

Paying attention to muscle weakness and reduced strength

• People with leukemia may feel their arms or legs are weaker than usual.
• Daily tasks such as climbing stairs, carrying things, walking, or exercising become more difficult, even though they were previously easy.
• If this decline in strength is persistent and increasingly noticeable, you should get a health check-up early.

Observing changes in skin color

• Skin may become pale, less rosy, or lack vitality.
• This can be a sign of anemia, a common condition in people with leukemia when the bone marrow does not produce enough healthy blood cells.
• When hemoglobin levels decrease, the ability to transport oxygen to organs in the body also decreases, leading to fatigue, dizziness, shortness of breath during exertion, and reduced physical strength.

When to seek medical attention?

• You should visit a medical facility if fatigue persists for more than a few weeks, does not improve after rest, or is accompanied by other leukemia symptoms such as prolonged fever, unexplained weight loss, swollen lymph nodes, easy bruising, unusual bleeding, or recurrent infections.
• A doctor can order a complete blood count and further specialized tests to determine the cause, thereby providing timely treatment if leukemia or other blood disorders are detected.

Symptom 3: Monitoring Unusual Weight Loss

Paying attention to unexplained weight loss

• Unexplained weight loss is one of the signs of leukemia and many other cancers that you should not ignore.
• If your weight significantly decreases despite not dieting, not increasing exercise, or not changing your lifestyle, you should proactively monitor it and seek medical attention to determine the cause.

Distinguishing physiological weight loss from pathological weight loss

• Slight weight gain or loss in certain periods is normal.
• However, if weight continuously decreases over many weeks or months without intention, this could be a warning sign that the body is experiencing problems, including leukemia or other serious conditions.
• Regularly recording your weight weekly will help you easily identify unusual changes.

Combining with monitoring other symptoms

• Weight loss due to leukemia usually does not occur in isolation but is accompanied by symptoms such as:
  • Persistent fatigue, lack of energy.
  • Body weakness, debility.
  • Fever or excessive night sweats.
  • Swollen lymph nodes, easy bruising, or unusual bleeding.
• If multiple symptoms occur simultaneously, you should visit a medical facility for early examination.

Do not mistake weight loss for a sign of good health

• Weight loss from a scientific diet or appropriate exercise often comes with a feeling of well-being, increased body flexibility, and improved mood.
• Conversely, weight loss related to illness often makes you feel exhausted, debilitated, with reduced stamina, and no sense of health despite losing weight.
• If this condition persists, a doctor may order blood tests and necessary examinations to find the cause and rule out leukemia or other illnesses.

Symptom 4: Beware of Abnormal Bleeding

Monitoring easily appearing bruises

• Easy bruising is one of the common signs of leukemia because the body no longer has enough platelets to support the clotting process.
• If large bruises appear after only minor impacts, or bruises appear without recalling an injury, you should monitor closely and seek medical attention if the situation recurs frequently.

Paying attention to prolonged bleeding

• People with leukemia may experience bleeding that takes longer than usual to stop, even with minor cuts or scratches.
• You should pay attention if you experience symptoms such as:
  • Prolonged bleeding after minor wounds.
  • Recurrent nosebleeds.
  • Blood that is difficult to clot even with minor injuries.

Observing bleeding gums

• Bleeding gums when brushing teeth or spontaneous bleeding without an apparent cause can also be a warning sign of leukemia.
• If this condition occurs frequently, especially when accompanied by easy bruising or nosebleeds, you should visit a medical facility for examination.

Why does leukemia cause bleeding and bruising?

• Leukemia affects the bone marrow, where blood cells are produced.
• When the platelet count decreases, the body's ability to stop bleeding is impaired, making you prone to subcutaneous bleeding, bruising, and prolonged bleeding.
• At the same time, red blood cell count can also decrease, leading to anemia and causing fatigue, paleness, and weakness.

When to seek medical attention?

• You should see a specialist if you frequently experience unexplained bruising, prolonged bleeding, or other unusual signs such as prolonged fever, weight loss, fatigue, swollen lymph nodes, or recurrent infections.
• A complete blood count and specialized tests will help the doctor determine the cause, thereby detecting leukemia or other blood disorders early for timely treatment.

Symptom 5: Recognizing Red Spots on the Skin

Observing unusual tiny red spots

• Tiny red spots on the skin (petechiae) can be one of the signs of leukemia that many people easily overlook.
• These spots are usually very small, round, red or reddish-purple, and appear suddenly on the skin unrelated to injury.

Distinguishing from common pimples or red marks

• Red spots caused by leukemia are often different from pimples, insect bites, or red skin after physical activity.
• You can recognize them by some characteristics such as:
  • Pinhead size.
  • Red or reddish-purple color.
  • No pus or inflammation.
  • Do not disappear when pressed lightly on the skin.
  • Appear without an apparent cause.

Pay attention if red spots appear in clusters

• These red spots often cluster in specific areas or groups on the arms, legs, chest, or other parts of the body.
• If the number increases or spreads, you should not be complacent because this could be a sign of low platelets due to leukemia or other hematological disorders.

Why do red spots appear on the skin?

• When the platelet count decreases, small capillaries under the skin are prone to bleeding, forming tiny hemorrhagic spots.
• This is a fairly typical manifestation in people with leukemia, especially when accompanied by easy bruising, bleeding gums, or nosebleeds.

When to seek medical attention?

• You should visit a medical facility if you notice red spots appearing suddenly, persisting, or accompanied by other leukemia symptoms such as fatigue, prolonged fever, weight loss, swollen lymph nodes, easy bruising, or recurrent infections.
• Early examination and blood tests will help determine the exact cause and increase the chances of effective treatment if the disease is detected in its early stages.

Symptom 6: Beware of Recurrent Infections

Monitoring the frequency of infections

• Recurrent infections are one of the signs of leukemia that can appear early but are often mistaken for a weakened immune system.
• If you continuously contract bacterial infections in a short period or relapse soon after recovery, you should proactively monitor your health and seek medical attention if the condition persists.

Why does leukemia increase the risk of infection?

• Leukemia (blood cancer) disrupts the production of white blood cells in the bone marrow.
• Although the number of white blood cells may increase, many cells develop abnormally and do not perform their protective function well.
• This weakens the immune system, making the body less able to fight off bacteria, viruses, and fungi that cause illness.

Common types of infections

• You should be aware if you frequently experience the following conditions:
  • Recurrent sore throats or tonsillitis.
  • Repeated ear infections.
  • Prolonged or hard-to-heal skin infections.
  • Continuous episodes of cold/flu, fever, or bacterial infections.

Signs that the immune system may be weakened

• Infections lasting longer than usual or responding poorly to treatment.
• Easy relapse of illness immediately after recovery.
• Frequent fever, fatigue, and feeling weak after each infection.

When to seek medical attention?

• If you experience multiple infections within a year, especially when accompanied by other leukemia symptoms such as prolonged fatigue, weight loss, swollen lymph nodes, easy bruising, unusual bleeding, or red spots on the skin, you should visit a medical facility for examination.
• A doctor can order a complete blood count and specialized tests to assess white blood cell function and detect leukemia or other blood disorders early.

Symptom 7: Pay Attention to Bone Pain

Monitoring unusual bone pain

• Bone pain is a less common sign of leukemia compared to fatigue or easy bruising, but it can still occur in some people with leukemia.
• If you frequently experience bone pain or deep bone pain that is not related to trauma or overexertion, you should proactively seek medical attention for examination.

Recognize notable symptoms

• You should pay attention to symptoms such as:
  • Dull or persistent bone pain.
  • Sensitive bones, pain when pressed.
  • Unexplained joint pain.
  • Pain that lasts for many days or progressively worsens.

Why does leukemia cause bone pain?

• Leukemia causes abnormal white blood cells to proliferate in the bone marrow.
• When the number of these cells accumulates excessively, the space inside the bone marrow narrows, creating pressure on bone tissue and causing pain.
• Additionally, cancer cells can also concentrate around bones or joints, causing patients to feel pain, tightness, or discomfort during movement.

Distinguishing from common causes of bone pain

• Bone pain due to exercise or injury often subsides after rest and appropriate treatment.
• In contrast, pain associated with leukemia tends to be prolonged, recurrent, or does not improve with rest.
• If the pain appears with other leukemia symptoms such as persistent fever, fatigue, weight loss, swollen lymph nodes, easy bruising, or recurrent infections, you should not be complacent.

When to seek medical attention?

• Go to a medical facility if bone or joint pain persists for no apparent reason, affects daily activities, or is accompanied by other abnormal signs.
• The doctor may order a complete blood count (CBC), imaging tests, or specialized tests to determine the cause and detect leukemia early if present.

Symptom 8: Recognizing risk factors

Understand that having risk factors does not mean you will get the disease

• Not everyone with risk factors will develop leukemia. However, recognizing risks helps you proactively monitor your health and get screened when necessary.
• If you belong to a high-risk group and experience leukemia symptoms such as persistent fatigue, easy bruising, persistent fever, or swollen lymph nodes, you should see a doctor early for evaluation.

Previous cancer treatment with chemotherapy or radiation therapy

• People who have been treated for cancer with chemotherapy or radiation therapy have a higher risk of developing certain types of leukemia than the general population.
• This risk is uncommon but requires long-term monitoring as directed by a doctor.

Having genetic disorders

• Some genetic diseases or syndromes can increase the risk of developing leukemia.
• If you have a history of genetic disorders related to blood or immunity, talk to your doctor about a plan for regular health monitoring.

Smoking

• Smoking increases the risk of many cancers, including some forms of leukemia.
• Quitting smoking not only helps reduce the risk of leukemia but also protects your heart, lungs, and improves overall health.

Family history of leukemia

• A family history of leukemia can increase your risk, although most cases of the disease are not hereditary.
• If many people in your family have blood disorders, you should inform your doctor during your health check-up.

Exposure to toxic chemicals

• Prolonged exposure to benzene and some other industrial chemicals can increase the risk of developing leukemia.
• People working in environments with chemicals should fully comply with labor protection measures, have regular health check-ups, and limit exposure when possible.

Proactive health monitoring if you are in a high-risk group

• If you have one or more risk factors, maintain a healthy lifestyle, have regular health check-ups, and undergo tests when indicated.
• Early detection of leukemia increases the chances of effective treatment and improves prognosis.

Part 2: The most accurate leukemia tests

Method 1: General health examination

Perform a clinical examination with a doctor

• If leukemia symptoms are suspected, the doctor will conduct a general examination to evaluate abnormal signs before ordering tests.
• Clinical examination cannot confirm that you have leukemia, but it is an important step to guide diagnosis and select appropriate tests.

Check for pale skin

• The doctor will observe the color of your skin, lips, and mucous membranes to detect signs of pallor or paleness.
• This can be a sign of anemia, a common condition in people with leukemia due to the bone marrow not producing enough healthy red blood cells.

Evaluate lymph nodes

• The doctor will palpate the lymph nodes in the neck, armpits, and groin to determine if they are swollen.
• Swollen lymph nodes are one of the common leukemia symptoms, but can also occur when the body has an infection or other medical conditions.
• Therefore, the doctor will combine multiple signs and tests to make an accurate diagnosis.

Check liver and spleen

• The doctor will examine the abdomen to evaluate the size of the liver and spleen.
• Enlarged liver or spleen can occur when abnormal white blood cells accumulate in the body.
• This condition can make the patient feel bloated, have upper abdominal discomfort, or feel full quickly after eating.

Note that these signs are not exclusive to leukemia

• Swollen lymph nodes or an enlarged spleen are not always leukemia.
• They can also be related to many other conditions such as viral infections, bacterial infections, or immune disorders.
• Therefore, the doctor will often combine clinical examination with a complete blood count, bone marrow test, or other specialized tests to determine the exact cause.

Early examination helps increase the chance of disease detection

• If you have leukemia symptoms such as persistent fatigue, persistent fever, weight loss, swollen lymph nodes, easy bruising, or unusual bleeding, see a doctor as soon as possible.
• Detecting the disease in the early stages helps make treatment more effective and improves long-term prognosis.

Method 2: Blood test

Blood test is an important step to detect leukemia

• When leukemia symptoms are suspected, the doctor often orders a complete blood count (CBC) to evaluate the number and quality of blood cells.
• This is one of the initial screening methods that helps detect abnormalities related to leukemia and other hematological diseases.

Which indicators will the doctor check?

• After collection, the blood sample will be analyzed to assess:
  • White blood cell count.
  • Red blood cell count.
  • Platelet count.
  • Indicators reflecting the bone marrow's hematopoietic function.
• People with leukemia may experience abnormal increases or decreases in white blood cells, while red blood cells and platelets may also be lower than normal.

When are additional specialized tests needed?

• If blood test results show abnormal values or suggest leukemia, the doctor may order additional diagnostic techniques to determine the cause and assess the extent of the disease.
• Some tests or imaging diagnostics that may be performed include:
  • Magnetic Resonance Imaging (MRI) in some cases to assess related lesions.
  • Computed Tomography (CT) to check organs or lymph nodes when indicated.
  • Lumbar puncture if necessary to assess the spread of cancer cells to the central nervous system, especially in some types of leukemia.

Blood test is not the final diagnostic step

• Abnormal blood test results are not enough to confirm that you have leukemia.
• The doctor will combine clinical symptoms, medical history, and other specialized tests, such as biopsy or bone marrow aspiration, to make an accurate diagnosis.

Do not delay health checks

• If you have leukemia symptoms such as persistent fatigue, unexplained fever, swollen lymph nodes, weight loss, easy bruising, or unusual bleeding, see a doctor early.
• Detecting the disease in the early stages helps the doctor choose appropriate treatment methods and improve the effectiveness of disease control.

Method 3: Bone marrow biopsy

Bone marrow biopsy helps confirm leukemia

• If initial tests suggest leukemia, the doctor may order a bone marrow biopsy or bone marrow aspiration to confirm the diagnosis.
• This is one of the most important tests to detect leukemia, determine the type of disease, and assist in developing an appropriate treatment plan.

Procedure

• The doctor will sterilize and anesthetize the area where the sample is taken, usually the hip bone.
• Then, a specialized needle is inserted into the bone marrow to collect a small amount of marrow fluid or bone marrow tissue.
• The entire procedure usually takes a short time, and the patient may feel some pressure or discomfort during the sample collection.

How is the bone marrow sample analyzed?

• The sample will be sent to the laboratory to check for the presence of abnormal white blood cells or cancer cells.
• At the same time, the doctor will evaluate the number, shape, and developmental stage of the cells in the bone marrow to determine if leukemia is present.

Additional tests may be needed

• Based on the biopsy results, the doctor may order additional specialized tests to accurately determine the type of leukemia, its progression, and the patient's risk.
• These tests also help select appropriate treatment methods and monitor treatment effectiveness during patient care.

Don't be too worried if a biopsy is ordered

• Bone marrow biopsy is a common procedure performed at specialized hematology and oncology centers.
• Although it may cause temporary discomfort, the results from this test provide crucial information for accurately diagnosing leukemia and implementing a timely treatment plan, thereby improving the prognosis for patients.

Method 4: Receiving diagnostic results

Wait for the doctor to provide an accurate diagnosis

• After completing the clinical examination and necessary tests, the doctor will synthesize the results to determine if you have leukemia.
• The time to receive results can range from a few days to several weeks, depending on the type of test and the analysis time at the laboratory.

If diagnosed with leukemia

• If the results confirm leukemia, the doctor will clearly explain:
  • The type of leukemia you have.
  • The stage of the disease.
  • Prognosis and appropriate treatment methods.
• Understanding the disease thoroughly will help patients be more proactive in their treatment and long-term monitoring.

Determine the rate of disease progression

• Leukemia is generally divided into two main groups:
  • Acute leukemia: The disease progresses rapidly, symptoms appear quickly, and often requires early treatment.
  • Chronic leukemia: The disease develops more slowly, in many cases there are no obvious symptoms for years and it is discovered during routine health check-ups.

Classification by affected white blood cell type

• The doctor will also identify the group of white blood cells affected to accurately classify the disease:
  • Lymphocytic leukemia: Affects lymphocytes, an important component of the immune system.
  • Myelogenous leukemia: Originates from myeloid cells in the bone marrow, which are precursors to many types of blood cells.

Common types of leukemia

• Some common types of leukemia include:
  • Acute Lymphoblastic Leukemia (ALL): Common in children but can also occur in adults.
  • Acute Myeloid Leukemia (AML): Can occur at all ages and is the most common acute type in adults.
  • Chronic Lymphocytic Leukemia (CLL): Primarily affects adults, progresses slowly, and many cases are asymptomatic in the early stages.
  • Chronic Myelogenous Leukemia (CML): Often appears in adults, the disease progresses gradually and may take many years to become apparent.

Discuss the treatment plan with your doctor

• After diagnosis, the doctor will develop a treatment plan based on the type of leukemia, disease stage, age, health status, and co-existing medical conditions.
• Adherence to treatment, timely follow-up appointments, and regular monitoring will contribute to improving treatment effectiveness and the quality of life for patients.

References

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Content edited by: Leigh Kennedy Ly.

Information reviewed and verified by expert: Benjamin Lewis.