Chronic lymphocytic leukemia (CLL) is a type of cancer that affects lymphocytes. It can be challenging to detect CLL early, because it does not cause symptoms in its early stages.

Lymphocytes are a type of white blood cell in the immune system. In CLL, the bone marrow produces too many lymphocytes. These can then build up in the bone marrow, travel into the bloodstream, and spread to lymph nodes and other organs, including the lungs, spleen, and liver.

According to the American Cancer Society, CLL is the most common type of leukemia in adults.

CLL can follow two different patterns. Some forms develop very slowly, meaning a person may not require treatment for a long time. Other forms grow faster, causing a more severe condition.

In this article, we discuss how doctors diagnose CLL and whether they can detect it in its early stages. We also examine CLL stages and symptoms and the outlook for people with the condition.

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CLL commonly does not cause any symptoms early on, making it difficult to detect in its early stages.

A doctor may detect CLL during a routine blood test they conduct for another reason.

As the condition develops, a person may begin to experience various symptoms. At this point, a doctor may find it easier to diagnose CLL.

A doctor may carry out several tests to diagnose CLL, such as blood tests, bone marrow tests, and biopsies.

Below, we discuss in detail some of the tests doctors use for CLL diagnosis.

Blood tests

A doctor usually takes a blood sample from a person’s arm for analysis to look for factors that may indicate CLL.

To diagnose the condition, a doctor may use one of two blood test types: complete blood count and blood cell exam or flow cytometry.

During complete blood count and blood cell exam, also known as peripheral blood smear, a doctor measures the levels of the different cells in the blood sample, including red blood cells, white blood cells, and platelets.

Additionally, they analyze the numbers of white blood cells, including lymphocytes. In people with CLL, there are too many lymphocytes, and their structure may also be unusual.

Flow cytometry involves using a machine to reveal certain substances on or in cells to identify specific cell types. This test can help see whether a person’s lymphocytes contain CLL cells. Flow cytometry tests can also help identify CLL cells in a person’s bone marrow and other bodily fluids.

Bone marrow tests

A doctor may take a sample of bone marrow to test. They commonly collect the sample from the back of a person’s pelvic bone during a procedure called aspiration and biopsy.

The doctor cleans the skin over the hip during bone marrow aspiration and injects a drug to numb the area and the surface of the bone. They then place a hollow needle into the bone and use a syringe to collect a small sample of liquid bone marrow for testing.

During biopsy, the doctor removes a small piece of the core of a person’s bone and bone marrow. This piece is around one-sixteenth of an inch in diameter and half an inch long.

The doctor removes this sample using a larger needle. They twist the needle as they push it down into the bone. This can cause a feeling of pressure or tugging but usually does not hurt.

Once the doctor removes the samples, they conduct several tests to look for certain factors. A pathologist may look at the sample under a microscope to gauge the size, shape, and other traits of white blood cells.

They may check:

  • whether CLL cells are present
  • whether the lymphocytes have abnormalities
  • the maturity of the lymphocytes

Gene tests

Genetic tests that doctors may also schedule to help diagnose CLL include:

  • Cytogenetic tests: A doctor will analyze a person’s bone marrow in a laboratory to look for chromosome changes due to CLL.
  • Fluorescent in situ hybridization: This test uses a special dye that only attaches to specific parts of particular chromosomes. The test can help healthcare professionals spot specific genes or chromosome changes resulting from CLL.
  • Molecular tests: Using this test, a healthcare professional can look at a person’s genes during cDNA sequencing. This allows them to see whether a person’s genes have changed or mutated due to CLL, indicating the aggressiveness of the condition.

Lymph node biopsy

During a lymph node biopsy, a healthcare professional removes all or part of a person’s lymph node and examines it under a microscope to check for cancer cells.

Doctors often use this procedure to diagnose lymphomas. However, they rarely use it for CLL.

A doctor may use a lymph node biopsy if the node has grown very large or to see whether leukemia has changed and become more aggressive.

Lumbar puncture

A lumbar puncture allows doctors to analyze the fluid that surrounds the brain and spinal cord.

A doctor numbs the area in the lower part of a person’s back over their spine and places a small, hollow needle between the bones of the spine and into the space surrounding the spinal cord. They use the needle to collect a sample of the spinal fluid.

Healthcare professionals often do not use this procedure to test for CLL. However, they may use it if they believe that the CLL cells have spread to the spinal fluid.

Symptoms of CLL usually develop slowly. However, in rare cases, the symptoms can develop rapidly.

Many people have no symptoms at all when they receive a CLL diagnosis. As it develops, symptoms may appear and vary in severity from person to person.

Common symptoms of CLL include:

Changes to the bone marrow can lead to anemia. Possible symptoms of anemia include:

CLL may also cause a person to develop a low platelet count, or thrombocytopenia. If the platelet count is low enough, an individual may experience spontaneous bleeding and tiny round dark red spots on the skin that health experts call petechiae.

Experts often distinguish five different stages of CLL using the Rai staging system. These stages depend on specific results of blood tests and physical examinations.

The stages of CLL are as follows:

  • Stage 0: A person has many lymphocytes, no enlargement of the lymph nodes, liver, or spleen, and a normal red blood cell and platelet count.
  • Stage 1: An individual has many lymphocytes, enlarged lymph nodes, no enlargement of the liver or spleen, and a normal red blood cell and platelet count.
  • Stage 2: A person has many lymphocytes, an enlarged spleen, and possibly an enlarged liver, and they may or may not have enlarged lymph nodes. If they have stage 2 CLL, they may also have a normal red blood cell and platelet count.
  • Stage 3: A person has many lymphocytes, and they may or may not have enlarged lymph nodes, spleen, or liver. In this stage of CLL, a person has a low red blood cell count, and their platelet count is near normal.
  • Stage 4: A person has many lymphocytes and may have enlarged lymph nodes, spleen, or liver. They may also have a low or normal red blood cell count and a low platelet count.

Health experts categorize these stages of CLL into low, intermediate, and high risk groups:

  • Stage 0 is low risk.
  • Stages 1 and 2 are intermediate risk.
  • Stages 3 and 4 are high risk.

Currently, there is no cure for CLL. Most people can live with the condition for many years, and some people can live for years without treatment or symptoms. However, over time, most individuals with CLL will require treatment.

A person may need treatment on and off for many years and sometimes may not need it for prolonged periods. People with CLL may need a doctor or support groups to help them adapt and learn to live with the condition.

A person with a CLL diagnosis may wish to ask a doctor specific questions to help them understand their condition, outlook, and treatment options.

Questions to ask upon receiving a CLL diagnosis

  • What stage is my CLL, and what does this mean?
  • Do I need to have other tests before deciding on treatment?
  • How much experience do you have in treating CLL?
  • Should I get a second opinion?

Questions to ask when deciding on a treatment plan

  • When should I begin my treatment?
  • What treatment options are available to me?
  • What treatment do you recommend?
  • What are the risks and potential side effects of the different treatment options available to me?
  • How often will you test my blood or bone marrow to track the progress of my treatment?
  • How do I prepare for treatment?
  • How long will my treatment last?
  • What can I expect during my treatment, and how will it impact my daily life?
  • What is the outlook for my condition?

Questions to ask during treatment

  • How do you know whether the treatment is working?
  • How can I manage the side effects of my treatment?
  • Are there any symptoms or side effects that I should immediately mention if they appear?
  • How can I contact your office during nights, holidays, or weekends?
  • Can you recommend a mental health professional that I can speak with if I begin to feel overwhelmed or depressed during treatment?

Questions to ask after treatment

  • What symptoms should I keep an eye out for?
  • What steps will we take if the treatment does not work or if my CLL comes back?
  • What follow-up appointments will I need?
  • When can I return to work?

CLL does not tend to cause symptoms early on, making it difficult to detect in the early stages. A doctor may identify CLL during a routine blood test for another reason.

A doctor may carry out several tests to diagnose CLL. These include blood tests, bone marrow tests, and genetic tests.