Chronic lymphocytic leukemia (CLL) is a slow-growing blood cancer. It can take a while for CLL to cause symptoms, and some people live with CLL for several years without realizing it. CLL is often not discovered until routine blood tests show unusual results.
Signs and symptoms of CLL may include:
Many other illnesses also cause these symptoms, so experiencing them does not necessarily mean you have CLL. You should always tell your doctor about any unusual symptoms or health concerns for proper diagnosis. If your doctor suspects CLL, they may order the following tests to make a diagnosis.
Your doctor may suggest that you get basic blood tests done if they think that you may have leukemia. You may also have blood tests done for other reasons, including as part of a regular physical exam. Blood tests often include a complete blood cell count (CBC), which counts how much of each type of blood cell is in your blood. If you have CLL, a CBC will usually show that you have high numbers of lymphocytes (white blood cells). A CBC can also show the other types of white blood cells that may be affected.
Other blood chemistry tests measure the levels of different substances. For example, your doctor may want you to have a lactate dehydrogenase test. Lactate dehydrogenase is a type of protein your cells release when they become damaged. Having high levels of lactate dehydrogenase may be a sign of disease.
If there is a chance you may have CLL, a physical exam can help your doctor identify possible signs of disease. During an exam, your doctor will probably measure your spleen size and look at your abdomen and lymph nodes for signs of any pain or swelling. Your doctor will likely ask about any symptoms you may be having, and ask you to describe any family history of health problems. At this exam, your doctor may also schedule you for additional tests.
Bone marrow tests are sometimes used to diagnose blood cancers. They are not always needed for CLL. However, they may be useful in certain cases for distinguishing between CLL and other diseases or for measuring whether treatments are working.
Bone marrow is tissue that produces blood cells and is found inside of certain bones. During a bone marrow biopsy and aspiration, a doctor will remove a small sample of tissue and fluid from the bone marrow — usually from the hip bone using a needle. During this procedure, you will typically be given medication to numb the area and may receive medication that helps you relax.
Blood samples, and occasionally bone marrow samples, can be further studied in a laboratory. There are several different types of white blood cells, and cancer can develop from any of them. CLL develops from a type of white blood cell called B cells, or B lymphocytes. Lab testing can more closely analyze your white blood cells, providing information about which type of blood cancer you have and which treatments are likely to work best. These tests can further inform your doctor about prognosis.
Laboratory tests may not be able to distinguish between CLL cells and small lymphocytic lymphoma (SLL) cells. These cells look the same and have some of the same genes and proteins. Usually, you receive a diagnosis of CLL if you have high levels of lymphocytes, and a diagnosis of SLL if you have lower levels of lymphocytes in addition to leukemia cells in the spleen or lymph nodes. Both of these types of the disease often warrant the same treatments.
Immunophenotyping tests can help your doctor provide a CLL diagnosis, and are often performed using a procedure called flow cytometry. Flow cytometry reads the proteins found on the outer surface of blood cells.
Fluorescence in situ hybridization (FISH) is another test that can identify certain gene changes. Often, leukemia cells have changes in specific genes or chromosomes (long pieces of DNA that contain a cell’s genes). FISH can count the number of chromosomes or show certain gene abnormalities.
Gene changes can also be measured through cytogenetic testing, which examines bone marrow cells.
Other tests can look for small changes, or mutations, in specific genes. The tumor protein p53 (or TP53) and immunoglobulin variable heavy chain (or IgVH) genes are often mutated in CLL cells. Finding out whether gene mutations are present can help you and your doctor understand more about your outlook.
An immunoglobulin test measures the levels of certain proteins called antibodies. Antibodies are normally made by B cells and play a role in fighting infection. People with CLL often have low levels of these antibodies because the cancerous B cells can’t make immunoglobulin properly.
CLL develops in the bone marrow. Once leukemia cells form, they also circulate around the body in the blood. Imaging tests, which take pictures of your tissues and organs, can show whether CLL cells have spread to other areas, including the spleen, liver, and lymph nodes. You may need imaging tests before treatment to help determine which treatments may be helpful. You may also need more imaging tests during treatment to show whether the treatment is working.
Types of imaging tests for CLL include:
The most important function of these tests is showing whether or not you have leukemia. However, CLL diagnostic tests can provide other important information as well.
Diagnostic tests can help determine the stage of your leukemia. This, in turn, can help you and your doctor understand which treatments may be most helpful and whether your outlook is likely to be good or bad.
If you have early-stage CLL, cancer cells have not spread to organs like the spleen and liver, and your levels of red blood cells and platelets are close to normal. You may not need aggressive treatments, and your outlook is likely to be good. If you have advanced-stage CLL, cancer cells may be found in the liver, spleen, or lymph nodes, and you may have low levels of red blood cells or platelets. Higher-stage CLL may need more aggressive treatments and may lead to a worse outlook.
Blood, bone marrow, and imaging tests may also uncover prognostic factors that help you understand your outlook. Risk factors that may mean you are likely to have a worse prognosis include:
Have you recently been diagnosed with chronic lymphocytic leukemia? Connecting with others who have also undergone a cancer diagnosis can help. At MyLeukemiaTeam, over 7,900 people with different types of leukemia gather to share advice and talk about their own experiences living with this disease.
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