What is chronic lymphocytic leukemia (CLL)?
Chronic lymphocytic leukemia (CLL) is a type of leukemia that causes your body to make abnormal white blood cells (lymphocytes) in your bone marrow. As the number of these abnormal cells grow, there is less room for healthy white and red blood cells and platelets. The cells can also spread to your lymph nodes, spleen, or liver. Because these white blood cells are not able to effectively defend the body from infections, you can experience illnesses, anemia, and bleeding.
CLL is the most common type of leukemia in adults. It tends to occur later in life, on average around age 70. This type of leukemia may be chronic and progress very slowly, or it can spread quickly and require therapy. Your treatment will depend on how the disease progresses.
Penn Medicine’s blood cancer care experts specialize in treating CLL. Although there’s no cure for the disease, therapies can allow you to live without symptoms, known as remission. Our experts have helped develop many of the current therapies for blood cancers, and we lead the largest bone marrow transplant program in our region. We also offer newer approaches that allow older adults to safely receive blood cancer therapies. With deep-rooted insights and experience, we can recommend the best treatment strategy for you.
Types of chronic lymphocytic leukemia
Chronic lymphocytic leukemia can be classified as either slow growing (indolent) or fast growing (aggressive). The type you have may determine whether or not you have symptoms and how the disease is treated.
Indolent CLL is slow growing and can remain stable without treatment for years. If your CLL is indolent, it means you have an increased number of lymphocytes in your blood, but your other blood cell counts are normal or only slightly below normal.
Sometimes people with CLL in the early stages discover their illness when their primary care physician orders routine tests or diagnostic tests for other symptoms. If you have slow growing CLL, you may not have symptoms of the disease.
Aggressive CLL is fast growing and requires more immediate treatment. In this type of CLL, there are too many lymphocytes, leaving little to no room for healthy blood cells. You may have symptoms of the disease.
When aggressive CLL goes untreated, you can develop complications, like anemia, bleeding, and difficulty fighting off infections. Some people with CLL complications may need a blood transfusion.
How CLL can affect you
One of the most common symptoms of CLL is enlarged lymph nodes in your neck, chest, or groin. This happens when lymphocytes build up in the nodes, causing them to swell. However, having swollen lymph nodes doesn’t necessarily mean that you have CLL because they’ll temporarily become enlarged when they produce antibodies to fight an infection. Other signs of CLL include:
- Fatigue and lethargy
- Night sweats
- Unexplained weight loss
- Unusual fullness after a meal
- Abdominal pain or swelling
- Fever and infections
- Bruising or bleeding, like nosebleeds or bleeding gums
How is CLL diagnosed?
Most people can be diagnosed with CLL based on a physical exam and blood tests, which include specialized testing in the lab to analyze your cells. A peripheral blood smear can identify CLL cells under the microscope, and a test called flow cytometry can confirm that the molecular markers on those cells are consistent with CLL. You might also have genetic testing, including cytogenetic studies to examine your chromosomes. These tests can help your doctor choose the right therapies for you. Sometimes a small sample of your bone marrow is also taken for examination.
Staging CLL
Staging your chronic lymphocytic leukemia, along with knowing its clinical behavior, will help us create a treatment plan specific to you. CLL stages are determined using the Rai staging system:
- Stage 0: In this stage, there are circulating CLL cells without other abnormalities.
- Stage I: Your lymph nodes are involved.
- Stage II: Your spleen is involved.
- Stage III: You are anemic.
- Stage IV: You have low platelets.
It's important to know that the Rai staging system is different from other staging systems. Traditional, solid tumor staging may predict prognosis, but under the Rai system, higher stages doesn’t necessarily mean you have a poorer outlook. Doctors use the Rai staging system along with other factors to predict prognosis.
Getting a second opinion from Penn Medicine
If you were diagnosed at another health care center and are coming to Penn Medicine for treatment or a second opinion, additional diagnostic tests may be necessary.
We use specific diagnostic imaging tools, tests, and procedures that are often more modern than what is available elsewhere. The results of these tools help us develop your personalized treatment plan.
Treatment approaches for CLL
If you’re not having CLL symptoms, your doctor may recommend watchful waiting, which means you don’t need to start treatment right away. You’ll see your health care team regularly so they can monitor you. If you are having symptoms, treatments can slow the growth of lymphocytes and put you in remission. There are several options, including medication, therapies, and stem cell transplants. Some of these treatments are used in combination.
Rated “exceptional” by The National Cancer Institute
Penn Medicine’s Abramson Cancer Center is a world leader in cancer research, patient care, and education. Our status as a national leader in cancer care is reflected in our continuous designation as a Comprehensive Cancer Center by the National Cancer Institute (NCI) since 1973, one of 7 such centers in the United States. The ACC is also a member of the National Comprehensive Cancer Network, one of a select few cancer centers in the U.S., that are working to promote equitable access to high-quality, advanced cancer care.
Related specialties
Patient stories
‘You won the lottery’: The very first CAR T cell patient
Bill Ludwig will forever be known as the first person successfully treated with a cellular therapy that kills cancer cells with his own immune system.
Improving care for patients with acute lymphocytic leukemia
A clinical trial gave Becky Yu access to treatment that would become the new standard of care for newly diagnosed acute lymphocytic leukemia.
Life, gained: Walter Styer’s CAR T story
Walter Styer’s 11+ life-filled years after being the 10th participant in an early trial, are a testament to the impact of CAR T cell immunotherapy.
How pickleball (and Penn Medicine) saved one patient’s life
With teamwork and determination, specialists at Penn Medicine solved Ronnie Recchia’s life-threatening medical mystery and got him back in the game.