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Identifying the stages of leukemia can provide important information about the progression of the condition that can help physicians determine the most appropriate treatments. Leukemia cells develop within the bone marrow and do not form masses or tumors, but instead affect the quantities of white blood cells, red blood cells and platelets within the body. Therefore, while most types of cancer are staged based on the size and spread of a primary tumor, the stages of leukemia are determined differently based on blood cell counts and the accumulation of leukemia cells within organs, such as the liver and spleen.

Rather than using traditional methods, such as the TNM staging system, to assign the stages of leukemia, a physician will first determine the subtype of the condition by evaluating the results of cytologic (cellular) tests, flow cytometry or other lab tests. Each leukemia subtype is then staged using a unique system:

  • Acute lymphocytic leukemia – Staged based on the type of lymphocyte and the maturity of the cells
  • Acute myelogenous leukemia – Staged using the French-American-British (FAB) system, which takes into account the number of healthy blood cells, the size and number of the leukemia cells, the changes in the chromosomes of the leukemia cells and other genetic abnormalities
  • Chronic lymphocytic leukemia – Staged using the Rai system, which considers three main factors: the number of lymphocytes in the blood; the degree of lymph node, spleen or liver enlargement and the presence of anemia or thrombocytopenia
  • Chronic myelogenous leukemia – Staged based on the number of diseased cells found in blood and bone marrow tests

The stages of leukemia relate generally to a patient’s prognosis, mainly in that patients who are diagnosed in early stages tend to have better outcomes. Nevertheless, the stage of the condition alone cannot predict a patient’s outcome with any degree of certainty, and furthermore, there is a wide range of outcomes for patients with the same stage of leukemia.

Stages of Chronic Leukemia

The Rai system is used to stage chronic leukemia:

  • Stage 0 – A patient has high levels of white blood cells, but no other physical symptoms.
  • Stage 1 – A patient has high levels of white blood cells and enlarged lymph nodes.
  • Stage 2 – A patient has high levels of white blood cells and is anemic. He or she may also have enlarged lymph nodes.
  • Stage 3 – A patient has high levels of white blood cells and is anemic. He or she may also have enlarged lymph nodes and/or an enlarged liver or spleen.
  • Stage 4 – A patient has high levels of white blood cells and low platelets. He or she may also be anemic, have enlarged lymph nodes and have an enlarged liver or spleen.

How is leukemia diagnosed?

Leukemia staging is generally determined by blood cell counts and the accumulation of leukemia cells within organs. When diagnosing leukemia, the test most commonly performed is a complete blood count (CBC), which measures:

  • White blood cell count
  • Red blood cell count
  • Platelet count
  • Hemoglobin concentration
  • Hematocrit concentration

If the results of a patient’s CBC are abnormal, additional testing will likely need to be performed. This might include:

  • Bone marrow aspiration – This procedure involves collecting a sample of liquid bone marrow, typically from the patient’s hip bone. After numbing the area, the physician will use a hollow needle to remove the cells.
  • Bone marrow biopsy – Similar to a bone marrow aspiration, a bone marrow biopsy involves removing a sample of bone marrow from the patient’s hip bone. However, while an aspiration involves collecting liquid bone marrow cells, a biopsy involves taking a small piece of bone that’s filled with marrow.
  • Cytogenetic analysis – This test is used to identify changes in chromosomes—for example, broken or missing chromosomes, rearranged chromosomes or the presence of extra chromosomes—since changes like these could indicate cancer or another medical condition.
  • Flow cytometry – Experts can use a device known as a flow cytometer to analyze cells collected in a sample. The sample is suspended within a fluid and then injected into the flow cytometer. Light illuminates the cells as they pass through a narrow channel one at a time, and sensors detect whether light is refracted or emitted from the cells. This process helps determine the cells’ physical and chemical characteristics.
  • Fluorescence in situ hybridization (FISH) – This technique involves exposing chromosomes to a small DNA sequence (a probe) with an attached fluorescent dye. The probe will find and stick to its matching sequence on one of the chromosomes, helping physicians visualize and map the genetic material within a patient’s cells.
  • Lumbar puncture (spinal tap) – During this procedure, a physician inserts a needle into the patient’s lower back to collect cerebrospinal fluid from the spinal canal. The sample will then be analyzed to detect the presence of cancer cells.

What to do if you’re diagnosed with leukemia

If you’ve received a leukemia diagnosis, you’re probably feeling incredibly overwhelmed. The most important thing you can do is reach out to a leukemia specialist, such as the ones at Moffitt Cancer Center. A leukemia expert will be able to address your concerns and provide you with critical information about the next steps to take. Before your initial consultation, you may want to write down a list of questions so that you don’t forget anything. You may also consider bringing along a family member or friend to provide emotional support and help remember important pieces of information.

Moffitt Cancer Center’s Approach to Leukemia

If you’d like to learn more about the stages of leukemia, the outstanding physicians in the Malignant Hematology Program at Moffitt Cancer Center can provide all of the information you need. These highly experienced physicians each specialize in a single disease discipline, such as leukemia. By focusing on one specific condition, our physicians have acquired extensive expertise, which translates to better treatments and outcomes for our patients.

Medically reviewed by Onyee Chan, MD, Malignant Hematology.

To consult with the experts at Moffitt about the stages of leukemia, Call 1-888-663-3488 or complete a new patient registration form online. When you do so, you can expect to be connected with a cancer expert as soon as possible. We’re proud to have disrupted the traditional patient care model to provide patients with rapid care, starting treatment quickly so that we can achieve the best possible outcomes.