Overview
Chronic lymphocytic leukemia (CLL) is a type of cancer of the blood and bone marrow — the spongy tissue inside bones where blood cells are made. With CLL, the most common chronic adult leukemia, one may feel well for years without needing treatment.1
The term “chronic” in chronic lymphocytic leukemia comes from the fact that it typically progresses more slowly than other types of leukemia. The term “lymphocytic” in chronic lymphocytic leukemia comes from the cells affected by the disease — a group of white blood cells called lymphocytes, which help the body fight infection.1
Chronic lymphocytic leukemia most commonly affects older adults. There are treatments to help control the disease.1
Symptoms
Many people with chronic lymphocytic leukemia have no early symptoms. Those who do develop signs and symptoms may experience:
- Enlarged, but painless, lymph nodes
- Fatigue
- Fever
- Pain in the upper left portion of the abdomen, which may be caused by an enlarged spleen
- Night sweats
- Weight loss
- Frequent infections1
Causes
Doctors aren’t certain what starts the process that causes chronic lymphocytic leukemia. What’s known is that something happens to cause one or more genetic mutations in the DNA of blood-producing cells. This mutation causes the blood cells to produce abnormal, ineffective lymphocytes.1
Beyond being ineffective, these abnormal lymphocytes continue to live and multiply, when normal lymphocytes would die. The abnormal lymphocytes accumulate in the blood and certain organs, where they cause complications. They may crowd healthy cells out of the bone marrow and interfere with normal blood cell production.1
Factors that may increase the risk of chronic lymphocytic leukemia include:
- Age. This disease occurs most often in older adults. On average, people diagnosed with chronic lymphocytic leukemia are in their 70s.
- Race. Whites 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 the 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.1
