Chronic lymphocytic leukemia
What is Chronic lymphocytic leukemia?
Chronic lymphocytic leukemia is a type of blood cancer that develops slowly over time. It happens when your bone marrow makes too many lymphocytes, a specific type of white blood cell. These abnormal cells build up in your blood and bone marrow, crowding out healthy blood cells.
CLL is the most common type of leukemia in adults. It usually affects people over age 60. The cancer grows slowly, which is why it is called chronic. Many people live for years with this condition, and some need no treatment at first.
Unlike other cancers, CLL often does not cause symptoms in the early stages. Many people discover they have it during routine blood work. Understanding this condition helps you work with your doctor to monitor changes and plan the right care approach.
Symptoms
- Swollen lymph nodes in the neck, underarms, or groin
- Feeling very tired or weak even after rest
- Fever without an obvious infection
- Night sweats that soak your sheets
- Unexplained weight loss over several months
- Frequent infections that take longer to heal
- Pain or fullness below the ribs on the left side
- Easy bruising or bleeding from minor injuries
Many people with early-stage CLL have no symptoms at all. The condition is often found during blood tests done for other reasons. Symptoms typically appear gradually as the disease progresses over months or years.
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Causes and risk factors
CLL happens when DNA changes in bone marrow cells cause them to make abnormal lymphocytes. These cells do not die when they should. They keep multiplying and crowd out healthy blood cells. Scientists do not know exactly what causes these DNA changes. Most cases happen without any clear cause or family history.
Age is the biggest risk factor, as CLL is rare before age 40. Men develop CLL more often than women. Having family members with CLL or other blood cancers slightly raises your risk. Exposure to certain chemicals like Agent Orange may increase risk. Being of European or North American ancestry is more common than Asian ancestry. No lifestyle factors like diet or smoking have been proven to cause CLL.
How it's diagnosed
CLL is usually first suspected when a routine blood test shows high white blood cell counts. Your doctor will order a complete blood count to check your levels of different blood cells. A blood smear lets lab technicians look at your cells under a microscope. Flow cytometry testing examines surface proteins on your white blood cells to identify CLL cells.
Surface light chains testing can help confirm the diagnosis, as CLL cells express either kappa or lambda light chains but not both. Your doctor may also order bone marrow tests, imaging scans, or genetic tests to understand your specific type of CLL. Because CLL requires specialized testing beyond standard panels, talk to your doctor about which tests you need. You can chat with our medical team about your concerns and next steps.
Treatment options
- Active surveillance for early-stage CLL with regular blood tests and checkups
- Targeted therapy drugs that attack specific proteins on cancer cells
- Chemotherapy medications to kill fast-growing cells
- Immunotherapy treatments that help your immune system fight cancer cells
- Stem cell transplant for younger patients with aggressive disease
- Radiation therapy for swollen lymph nodes causing symptoms
- Eating a nutrient-dense diet to support your immune system
- Getting adequate rest and managing stress to support overall health
- Avoiding infections by practicing good hygiene and avoiding sick contacts
- Working with a cancer specialist who focuses on blood cancers
Frequently asked questions
Chronic leukemia grows slowly over months or years, while acute leukemia develops quickly over days or weeks. Chronic lymphocytic leukemia often needs no immediate treatment. Acute leukemia requires urgent treatment. CLL mainly affects older adults, while acute leukemia can occur at any age.
Many people with early-stage CLL live normal lives for years without treatment. The condition progresses slowly in most cases. Some people need treatment eventually, while others never do. Regular monitoring with your doctor helps you plan care as needed.
CLL specifically affects B lymphocytes, a type of white blood cell that fights infection. It grows more slowly than most other leukemias. CLL mainly affects older adults, with an average age of diagnosis around 70. It often requires a watch-and-wait approach rather than immediate treatment.
A complete blood count is usually the first test to show abnormal white blood cell levels. Flow cytometry examines proteins on cell surfaces to identify CLL cells. Surface light chains testing shows whether cells express kappa or lambda light chains, helping confirm diagnosis. Your doctor may order additional specialized tests based on these results.
No, many people with early-stage CLL do not need immediate treatment. Doctors often recommend active surveillance, also called watch and wait. This means regular checkups and blood tests to monitor the disease. Treatment starts when symptoms appear or blood counts change significantly.
DNA changes in bone marrow cells cause them to make abnormal lymphocytes that do not die normally. These cells keep multiplying and accumulating over time. Scientists do not fully understand what triggers these DNA changes. Most cases occur without any known cause.
While lifestyle changes cannot cure CLL, they can support your overall health during treatment. Eating nutrient-rich foods helps your immune system function better. Getting enough sleep and managing stress support your body during cancer care. Avoiding infections is important because CLL weakens your immune response.
CLL has a slight genetic component, but most people with CLL have no family history of the disease. Having a first-degree relative with CLL does increase your risk somewhat. However, the overall chance is still small. Genetic testing is not typically recommended for family members.
Survival rates for CLL vary widely based on stage and other factors. Many people live 10 years or more after diagnosis. Some people with slow-growing CLL live normal lifespans. Newer targeted therapies have improved outcomes significantly in recent years.
See your doctor if you have swollen lymph nodes that last more than two weeks. Unexplained fatigue, frequent infections, or night sweats also need evaluation. Easy bruising or bleeding should be checked promptly. Regular checkups with blood work can catch CLL before symptoms appear.