Chronic lymphocytic leukemia (CLL) is a type of leukemia. Leukemia is cancer that affects the blood and bone marrow. Bone marrow is the spongy tissue inside bones where blood cells are made.

The term "chronic" in chronic lymphocytic leukemia refers to the slower progression of this cancer. CLL typically progresses more slowly than other types of leukemia. The term "lymphocytic" refers to the cells affected by the disease. The cells are a group of white blood cells called lymphocytes. Lymphocytes help your body fight infection.

Treatments for chronic lymphocytic leukemia may include a "watch and wait" approach, targeted therapy, chemotherapy, immunotherapy and bone marrow transplant, also known as bone marrow stem cell transplant. Other treatment options may include CAR-T cell therapy, radiation therapy and clinical trials.

Chronic lymphocytic leukemia symptoms may not happen right away. Symptoms may develop as the cancer progresses. When symptoms happen, they may include:

• Swollen lymph nodes, which might feel like a lump under the skin. They happen most often in the neck, armpit and groin.
• Fever.
• Drenching night sweats.
• Fatigue.
• Weight loss without trying.
• Loss of appetite.
• Pain in the upper left part of the belly, which may be caused by an enlarged spleen.
• Frequent infections.

When to see a doctor

Make an appointment with a healthcare professional if you have any symptoms that worry you.

It's not clear what causes chronic lymphocytic leukemia. Cancer happens when cells develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to make many more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells. In chronic lymphocytic leukemia, the cancer cells can build up in the blood, bone marrow, lymph nodes and other parts of the body.

Factors that may increase the risk of chronic lymphocytic leukemia include:

• Your age. Chronic lymphocytic leukemia happens most often in adults older than 55.
• Your race. White people are more likely to develop chronic lymphocytic leukemia than are people of other races.
• Family history of blood and bone marrow cancers. A family history of chronic lymphocytic leukemia or other blood and bone marrow cancers may increase your risk.
• Exposure to chemicals. Certain herbicides and insecticides, including Agent Orange used during the Vietnam War, have been linked to an increased risk of chronic lymphocytic leukemia.
• A condition that causes excess lymphocytes. Monoclonal B-cell lymphocytosis (MBL) causes an increased number of a type of lymphocyte, called B lymphocytes, in the blood. For a small number of people with MBL, the condition may develop into chronic lymphocytic leukemia. If you have MBL and also have a family history of chronic lymphocytic leukemia, you may have a higher risk of developing cancer.

Chronic lymphocytic leukemia may cause complications such as:

• Frequent infections. If you have chronic lymphocytic leukemia, you may get infections more often. These infections can be serious. Sometimes infections happen because your blood doesn't have enough germ-fighting antibodies, called immunoglobulins. Your healthcare professional might recommend regular immunoglobulin infusions.
• A switch to a more aggressive form of cancer. A small number of people with chronic lymphocytic leukemia may develop a more aggressive form of cancer called diffuse large B-cell lymphoma. This is sometimes referred to as Richter syndrome.
• Increased risk of other cancers. People with chronic lymphocytic leukemia have an increased risk of other types of cancer. These include skin cancer and cancers of the lung and the digestive tract.
• Immune system attacks. A small number of people with chronic lymphocytic leukemia may develop an immune system reaction that causes the disease-fighting cells of the immune system to mistakenly attack the red blood cells. This is called autoimmune hemolytic anemia. The immune system also may attack the blood cells that help blood clot, called platelets. This attack is called autoimmune thrombocytopenia.

Diagnosis of chronic lymphocytic leukemia often begins with a physical exam. The exam checks for swollen lymph nodes in the neck, underarms and groin and an enlarged spleen. Other tests and procedures include blood tests, imaging tests and taking a sample of tissue for lab testing.

Blood tests

Tests and procedures used to diagnose chronic lymphocytic leukemia include blood tests that:

• Count the number of cells in a blood sample. A complete blood count may be used to count the number of lymphocytes in a blood sample. A high number of B cells, one type of lymphocyte, could mean chronic lymphocytic leukemia.
• Show the size, shape and appearance of cells. A peripheral blood smear may be used to see what cells in the blood look like. In chronic lymphocytic leukemia, the smear may show a lot of small, round lymphocytes. These are sometimes called smudge cells.
• Identify proteins on the surface of the cancer cells. Chronic lymphocytic leukemia cells have certain proteins on their surfaces that help identify them. These proteins are known as markers. These markers also can help predict how aggressive the cells are.
• Look for changes in the cancer cell DNA. Cancer happens when cells get changes in their DNA. Lab tests can show which DNA changes are present in the leukemia cells.

Other tests

Your healthcare team may recommend more tests to help with diagnosis, such as:

• Bone marrow biopsy and aspiration. Bone marrow aspiration and biopsy are procedures that involve collecting cells from the bone marrow. The cells are sent for testing.

  A healthcare professional may recommend this test if blood counts are low and there isn't a clear reason for the low counts.

• Imaging tests. Imaging tests make pictures of the body. A healthcare professional may recommend imaging tests for CLL if there are areas of concern in the body or to help guide treatment. Tests might include CT and positron emission tomography (PET) scans.

Treatments for chronic lymphocytic leukemia may include a "watch and wait" approach, targeted therapy, chemotherapy, immunotherapy and bone marrow transplant, also known as bone marrow stem cell transplant. Other treatment options may include CAR-T cell therapy, radiation therapy and clinical trials. Which treatment is right for you depends on whether you have symptoms and the extent of your cancer, called the stage. Your healthcare team also considers how quickly the cancer is growing, your overall health and what you prefer.

Watch and wait

If your chronic lymphocytic leukemia doesn't cause symptoms, you may not need treatment right away. Instead, you may have checkups every few months. The checkups help your healthcare team watch your condition to see if your cancer progresses.

Targeted therapy

Targeted therapy for cancer is a treatment that uses medicines that attack specific proteins in cancer cells. By blocking these proteins, targeted treatments can cause cancer cells to die.

Targeted therapy is often the first treatment for chronic lymphocytic leukemia. You may take a combination of targeted therapy medicines. Targeted therapy also may be used when other treatments haven't worked, known as refractory chronic lymphocytic leukemia. Or it may be used for cancer that comes back after treatment, called relapsed chronic lymphocytic leukemia.

Side effects of targeted therapy may include diarrhea, liver issues, high blood pressure, and issues with blood clotting and wound healing. Side effects also may include fatigue, mouth sores and nail changes. Most side effects go away after treatment is done.

Chemotherapy

Chemotherapy treats cancer with strong medicines. There are many chemotherapy medicines. Most chemotherapy medicines are given through a vein. Some come in pill form.

Chemotherapy may be a treatment for chronic lymphocytic leukemia. You may take several chemotherapy medicines at one time. Chemotherapy also may be combined with immunotherapy. Chemotherapy may be the first line treatment for older adults or others who can't tolerate targeted therapy. Chemotherapy also may be used for chronic lymphocytic leukemia that has transformed into a more aggressive cancer.

Side effects of chemotherapy depend on the medicines you're given. Common side effects are nausea and hair loss. Serious long-term complications can happen, such as heart disease, lung damage, infertility and secondary cancers.

Immunotherapy

Immunotherapy for cancer is a treatment with medicine that helps the body's immune system kill cancer cells. The immune system fights off diseases by attacking germs and other cells that shouldn't be in the body. Cancer cells survive by hiding from the immune system. Immunotherapy helps the immune system cells find and kill the cancer cells.

Immunotherapy may be combined with chemotherapy to treat chronic lymphocytic leukemia. Immunotherapy also may be used for relapsed or refractory chronic lymphocytic leukemia.

Side effects of immunotherapy may include fever, chills, weakness, dizziness, aches, upset stomach and vomiting. Rarely, some immunotherapy treatments can cause an allergic reaction.

Bone marrow transplant

A bone marrow transplant, also called a bone marrow stem cell transplant, involves putting healthy bone marrow stem cells into the body. These cells replace cells hurt by chemotherapy and other treatments. Stem cells can come from your own body, called an autologous transplant. Stem cells also can come from a donor, called an allogeneic transplant.

As new and more-effective treatments have been developed, bone marrow transplant has become less common for treating chronic lymphocytic leukemia. However, an allogeneic bone marrow transplant may be a treatment option for some people with relapsed or refractory chronic lymphocytic leukemia.

Short-term side effects of a bone marrow transplant may include upset stomach, vomiting and not feeling hungry. They also may include fatigue, mouth sores, hair loss and skin reactions. Long-term side effects may include infertility, secondary cancers, organ damage, weakness in the bones or muscles, and cataracts.

CAR-T cell therapy

Chimeric antigen receptor (CAR)-T cell therapy trains the immune system cells to fight leukemia. This treatment begins with removing some white blood cells, including T cells, from the blood.

The cells are sent to a lab. In the lab, the cells are treated so that they make special receptors. The receptors help the cells recognize a marker on the surface of the leukemia cells. Then the cells go back into the body. They find and destroy leukemia cells.

CAR-T cell therapy may be an option for some people with refractory or relapsed CLL. CAR-T cell therapy may only be used after at least two other treatments have been tried.

Side effects of CAR-T cell therapy may include fever, upset stomach, headache and confusion. They also may include dizziness, rash, rapid heartbeat, trouble breathing and low blood pressure.

Radiation

Radiation therapy treats cancer with powerful energy beams. The energy can come from X-rays, protons or other sources. During radiation therapy, you lie on a table while a machine moves around you. The machine directs radiation to precise points in your body.

For chronic lymphocytic leukemia, radiation therapy may only be used to ease symptoms and improve quality of life.

Radiation therapy side effects include fatigue and skin irritation at the site where the radiation is aimed. Other side effects depend on where the radiation is aimed. Radiation to the neck can cause dry mouth and damage the thyroid. Radiation to the chest can damage the heart and lungs.

Clinical trial

Clinical trials are studies of new treatments. These studies provide a chance to try the latest treatments. The risk of side effects might not be known. Ask your healthcare team if you might be able to be in a clinical trial.

Monitoring after treatment

After treatment is complete, you may have frequent follow-up appointments to see if the cancer has come back, known as a relapse. You may have repeat blood and imaging tests to check for a relapse.

Treatment complications

Treatments for chronic lymphocytic leukemia may have complications, including:

• Bone marrow suppression. When the bone marrow is suppressed, it can't produce enough blood cells, including white blood cells. White blood cells help fight infections. With a lower amount of white blood cells, you are at a higher risk of infections.
• Febrile neutropenia. Febrile neutropenia is a serious condition that can happen in people being treated for cancer. Febrile means having a fever. Neutropenia means having a low number of neutrophils, a type of white blood cell that helps fight infections. In febrile neutropenia, the body is trying to fight an infection but doesn't have enough neutrophils.
• Medicine toxicity. Some medicines used to treat cancer can be harmful to the body. They can cause organ damage and other issues. Whether a medicine is toxic depends on the type and how much you receive. There are many different medicine options. Your healthcare team can work with you to find the best medicines for you.
• Reactivating viruses. If you have had a viral infection in the past, such as hepatitis B or hepatitis C, some treatments can cause the virus to become active again. This can lead to liver inflammation, liver damage and other complications.
• Tumor lysis syndrome. Tumor lysis syndrome is a serious condition that can happen when cancer cells break down quickly after treatment or randomly. When these cells die, they release substances into the bloodstream that can overwhelm the body. This can lead to issues with the kidneys and other organs. You may take medicines to treat or prevent harmful side effects.

No alternative treatments have been proved to cure chronic lymphocytic leukemia.

Alternative treatments for coping with fatigue

Some alternative medicine therapies may help you cope with fatigue. Many people with chronic lymphocytic leukemia have fatigue. Your healthcare team can treat fatigue by controlling the underlying causes. However, medicines alone usually aren't enough. You may find relief through alternative therapies, such as:

• Acupuncture.
• Exercise.
• Massage.
• Yoga.

Talk with your healthcare professional about your options. Together you can come up with a plan to help you cope with fatigue.

With time, you'll likely find what helps you cope with the uncertainty and worry of a cancer diagnosis. Until then, you may find that it helps to:

Learn enough about chronic lymphocytic leukemia to make decisions about your care

Ask your healthcare team about your cancer, including your test results, treatment options and, if you want, your prognosis. As you learn more about chronic lymphocytic leukemia, you may become more confident in making treatment decisions.

Keep friends and family close

Keeping your close relationships strong can help you deal with your chronic lymphocytic leukemia. Friends and family can provide the practical support you may need, such as helping take care of your home if you're in the hospital. And they can serve as emotional support when you feel overwhelmed by having cancer.

Find someone to talk with

Find someone who is willing to listen to you talk about your hopes and worries. This person may be a friend or family member. The concern and understanding of a counselor, medical social worker, clergy member or cancer support group also may be helpful.

Ask your healthcare team about support groups in your area. Other sources of information include the National Cancer Institute, the American Cancer Society, Blood Cancer United and the Lymphoma Research Foundation. Find support online through Mayo Clinic Connect, which is a community where you can connect with others for support, practical information and answers to everyday questions.

Make an appointment with a healthcare professional if you have any symptoms that worry you.

If your healthcare professional thinks you might have chronic lymphocytic leukemia, you may be referred to a doctor who specializes in diseases of the blood and bone marrow, called a hematologist.

Because appointments can be brief, it's a good idea to be prepared. Here's some information to help you get ready.

What you can do

• Be aware of anything you need to do ahead of time. At the time you make the appointment, ask if there's anything you need to do in advance, such as restrict your diet.
• Write down symptoms you have, including any that may not seem related to the reason for which you scheduled the appointment.
• Write down important personal information, including major stresses or recent life changes.
• Make a list of all medicines, vitamins and supplements you're taking and the doses.
• Take a family member or friend along. It can be hard to remember all the information you get during an appointment. Someone who goes with you may remember something that you missed or forgot.
• Write down questions to ask your healthcare team.

For chronic lymphocytic leukemia, some basic questions include:

• Do I have chronic lymphocytic leukemia?
• What is the stage of my chronic lymphocytic leukemia?
• Will I need more tests?
• What are the treatment options?
• How much does each treatment prolong my life or increase my chances of a cure?
• What are the potential side effects of each treatment?
• How will each treatment affect my daily life?
• What treatment options have shown the best results?
• What would you recommend to a friend or family member in my situation?
• Should I see a specialist?
• Are there any brochures or other printed material that I can take with me? What websites do you recommend?
• What will determine whether I should plan for a follow-up visit?

Don't hesitate to ask other questions.

What to expect from your doctor

Be prepared to answer questions, such as:

• When did your symptoms begin?
• Do your symptoms happen all the time or do you have them now and then?
• How bad are your symptoms?
• What, if anything, seems to make symptoms better?
• What, if anything, seems to make symptoms worse?
• Have you had any fevers, night sweats or weight loss?
• Have you noticed any lumps, swelling or pain anywhere in your body?
• What are your biggest worries about your diagnosis or treatment?

If you're diagnosed with chronic lymphocytic leukemia (CLL), the next step is to determine the cancer's extent, called the stage. Imaging tests and blood tests may be used to determine the stage of your chronic lymphocytic leukemia. Your healthcare team uses the cancer stage to help create your treatment plan.

Chronic lymphocytic leukemia stages can use letters or numbers. In general, the earliest stages of cancer may not cause symptoms and don't need to be treated right away. People with cancer in the later stages may have symptoms and need treatment right away. The numbered stages include:

• Stage 0 chronic lymphocytic leukemia. At stage 0, the number of lymphocytes in the blood is higher than usual. This is a condition known as lymphocytosis.
• Stage 1 chronic lymphocytic leukemia. Stage 1 involves lymphocytosis with enlarged lymph nodes.
• Stage 2 chronic lymphocytic leukemia. Stage 2 involves lymphocytosis with an enlarged spleen or liver. The lymph nodes also may be enlarged.
• Stage 3 chronic lymphocytic leukemia. Stage 3 involves lymphocytosis and a condition characterized by a lack of healthy red blood cells, called anemia. Stage 3 also may include an enlarged spleen or liver and enlarged lymph nodes.
• Stage 4 chronic lymphocytic leukemia: Stage 4 involves lymphocytosis and a condition characterized by low platelet counts, called thrombocytopenia. Stage 4 also may include an enlarged spleen or liver, enlarged lymph nodes, and anemia.

The lettered stages include:

• Stage A is lymphocytosis with less than three lymph nodes regions involved.
• Stage B is lymphocytosis with three or more lymph node regions involved.
• Stage C is lymphocytosis with anemia or thrombocytopenia. The lymph nodes and an enlarged spleen may or may not be involved.

Survival rates are different for each person with chronic lymphocytic leukemia. Healthcare professionals use something called a prognostic score to determine the chances of surviving certain types of cancers. Prognostic scores for chronic lymphocytic leukemia range from 0 to 10. The higher your score, the lower your chance of survival. Your score is determined by:

• Your age.
• Whether certain gene changes are present in your cancer.
• How much of a specific protein is in your blood.
• The stage of your cancer.

For example, chronic lymphocytic leukemia has a five-year survival rate of about 90% at a score of 0 to 1. The 10-year survival rate for a score of 0 to 1 is about 86%. As the score gets higher, the survival rate gets lower. For chronic lymphocytic leukemia with a score of 7 to 10, the chance of surviving at least five years is about 23%. The 10-year survival rate for a score of 7 to 10 is 0%.

Keep in mind that survival statistics take five or 10 years to collect. The most recent survival rates include people who had treatment for chronic lymphocytic leukemia more than five years ago. These people may not have had access to the latest treatments. Over the last few decades, chronic lymphocytic leukemia death rates have been falling and survival rates have been increasing.