Diagnosing leukaemia involves several important steps that help doctors identify the type of disease and create the best treatment plan for each patient. Understanding when to seek testing and what to expect during the diagnostic process can help reduce anxiety and uncertainty.

When Should You Seek Diagnostic Testing?

You should consider seeking medical evaluation if you experience persistent signs or symptoms that worry you. Leukaemia symptoms can be vague and often resemble those of common illnesses like the flu, which means they can be easy to overlook at first^[2]. This is why many people may dismiss early warning signs as nothing serious.

Make an appointment with your doctor if you notice any lasting symptoms that don’t go away. These might include ongoing tiredness that doesn’t improve with rest, frequent infections that keep coming back, unexplained weight loss, or unusual bleeding and bruising^[2]. You might also notice swollen lymph nodes, which are small glands in your neck, armpits, or groin, or experience night sweats that soak through your clothing.

Sometimes leukaemia is discovered unexpectedly during routine blood tests performed for completely different reasons^[2]. This is particularly common with chronic forms of leukaemia, which develop slowly over time. Your doctor may find abnormal blood cell counts even before you notice any symptoms.

Classic Diagnostic Methods for Leukaemia

When your doctor suspects leukaemia, they will begin with a thorough evaluation that includes both physical examination and laboratory testing. The diagnostic process is designed to not only confirm whether leukaemia is present, but also to identify which specific type you have, as this determines your treatment plan.

Physical Examination

During a physical exam, your doctor will look for physical signs that might indicate leukaemia. They will check for pale skin, which can signal anaemia (a condition where you don’t have enough healthy red blood cells)^[10]. Your doctor will also feel for swelling in your lymph nodes, particularly in your neck, armpits, and groin.

The examination includes checking your abdomen to see if your liver or spleen is enlarged. These organs can become larger when leukaemia cells build up inside them^[10]. Your doctor might press gently on different areas of your belly to check for any tenderness or unusual swelling.

Blood Tests

Blood tests are usually the first step in diagnosing leukaemia. A complete blood count, or CBC, is the most common initial test^[3]. This test measures the levels of different types of blood cells in your blood. By examining a sample of your blood, your doctor can determine if you have abnormal levels of red blood cells, white blood cells, or platelets (cells that help your blood clot).

In leukaemia, blood tests may reveal several unusual findings. You might have too many white blood cells, or you might have too few. Sometimes the white blood cells present are immature cells that shouldn’t normally be found in the bloodstream^[10]. The test might also show that you have lower than normal numbers of red blood cells and platelets, which explains symptoms like tiredness and easy bruising.

However, not all types of leukaemia cause leukaemia cells to circulate in the blood. In some cases, the abnormal cells remain in the bone marrow, which is the soft, spongy tissue inside your bones where blood cells are made^[10]. This is why additional testing is often necessary.

Bone Marrow Tests

If blood tests suggest leukaemia, your doctor will likely recommend a bone marrow examination to confirm the diagnosis. There are two main types of bone marrow tests: bone marrow aspiration and bone marrow biopsy^[10]. These procedures are often performed at the same time.

During a bone marrow aspiration, a healthcare professional uses a thin needle to remove a small amount of liquid bone marrow. This is usually taken from a spot in the back of your hip bone, also called the pelvis^[10]. The bone marrow biopsy involves removing a small piece of bone tissue along with the marrow inside it.

These samples are then sent to a laboratory where specialists look for leukaemia cells under a microscope. The bone marrow test helps determine which type of leukaemia you have and how severe it is^[3]. This information is crucial because different types of leukaemia require different treatments.

Specialized Laboratory Tests

Once leukaemia cells are identified, your samples will undergo more specialized testing. These tests examine the specific characteristics of the leukaemia cells to provide detailed information about your disease^[10]. This might include looking at the cells’ appearance, checking for specific proteins on their surface, and analyzing their genetic makeup.

Genetic tests look for gene and chromosome changes in the leukaemia cells^[7]. These tests can identify specific genetic abnormalities that affect how the disease behaves and responds to treatment. Some genetic changes mean the leukaemia is more likely to respond well to certain treatments, while others might indicate a more aggressive disease.

Additional Diagnostic Procedures

Depending on your symptoms and test results, your doctor might order additional tests to see if the leukaemia has spread to other parts of your body. Imaging tests such as X-rays, CT scans, or ultrasounds can help identify any areas where leukaemia cells have accumulated outside the bone marrow^[7].

A lumbar puncture, also called a spinal tap, may be performed to check if leukaemia has spread to the fluid around your brain and spinal cord. This procedure involves collecting and testing cerebrospinal fluid (CSF), which is the liquid that surrounds your brain and spinal cord^[7]. While this might sound concerning, it’s an important test to ensure comprehensive treatment planning.

Diagnostic Tests Used for Clinical Trial Qualification

If you’re considering participating in a clinical trial, you’ll need to undergo specific diagnostic tests to determine whether you meet the trial’s entry requirements. Clinical trials have strict criteria about who can participate, and these criteria are based on precise measurements of your disease.

Clinical trials for leukaemia typically require detailed information about your specific type of leukaemia and how advanced it is. This means you’ll need comprehensive blood testing and bone marrow examination similar to what was done for your initial diagnosis. The trial doctors need to confirm your exact leukaemia subtype and verify that you haven’t received certain treatments before^[6].

Genetic testing becomes particularly important for clinical trial qualification. Many modern clinical trials focus on treating leukaemia with specific genetic characteristics. Your leukaemia cells will be analyzed using advanced techniques like next-generation sequencing, which looks at multiple genes at once to identify specific mutations or changes^[6]. The presence or absence of certain genetic markers determines whether you’re eligible for particular trials.

Clinical trials often require baseline measurements of your overall health and organ function. This typically includes blood tests to check how well your kidneys and liver are working, because these organs need to be healthy enough to process the trial medications. You might also need an electrocardiogram (ECG or EKG), which measures your heart’s electrical activity, to ensure your heart is functioning properly.

Imaging tests may be required before you can join a trial. These might include CT scans, MRI scans, or ultrasounds to measure any enlarged lymph nodes, spleen, or liver. These baseline images help trial researchers track how well the treatment is working over time by comparing new images to the ones taken before treatment started.

For some trials, particularly those involving targeted therapies (treatments that attack specific features of cancer cells), you may need specialized molecular testing. This testing looks for very specific proteins or genetic markers on your leukaemia cells. For example, some trials only accept patients whose leukaemia cells have a particular protein called CD20 on their surface, or those with specific chromosome changes.

Throughout a clinical trial, you’ll undergo regular testing to monitor how your disease responds to treatment. This usually includes frequent blood tests and periodic bone marrow examinations. These monitoring tests serve two purposes: they help ensure the treatment is working and allow researchers to detect any concerning side effects early.

Your overall physical condition, called your performance status, is also evaluated for clinical trial entry. Doctors assess whether you’re able to care for yourself and carry out daily activities. This helps ensure you’re strong enough to tolerate the trial treatment. Some trials accept patients with lower performance status, while others require participants to be more physically active.

Age and previous treatment history are important factors in clinical trial qualification. Some trials specifically focus on older adults, while others are designed for children or young adults. Your treatment history matters because many trials require that you haven’t received certain types of chemotherapy or other treatments before, or conversely, some trials only accept patients whose leukaemia has come back after previous treatment.