Chronic Lymphocytic Leukemia (CLL)

Expert Care and Treatment for Leukemia and Related Disorders

Dana-Farber Brigham Cancer Center’s Adult Leukemia Program within the Hematologic Oncology Treatment Center includes hematologists, medical oncologists, pathologists, and radiation therapists who specialize in treating patients with all types of leukemia and related blood and bone marrow disorders.

Your care team will collaborate to develop a comprehensive, personalized treatment plan that offers the most advanced therapies and an array of supportive resources.

Adult Leukemia Program

What Is Chronic Lymphocytic Leukemia?

Chronic lymphocytic leukemia (CLL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). 

Leukemia may affect red blood cells, white blood cells, and platelets. 

Normally, the body makes blood stem cells (immature cells) that become mature blood cells over time. A blood stem cell may become a myeloid stem cell or a lymphoid stem cell. 

A myeloid stem cell becomes one of three types of mature blood cells: 

  • Red blood cells that carry oxygen and other substances to all tissues of the body 
  • White blood cells that fight infection and disease 
  • Platelets that form blood clots to stop bleeding 

A lymphoid stem cell becomes a lymphoblast cell and then one of three types of lymphocytes (white blood cells): 

  • B lymphocytes that make antibodies to help fight infection 
  • T lymphocytes that help B lymphocytes make antibodies to fight infection 
  • Natural killer cells that attack cancer cells and viruses 

In CLL, too many blood stem cells become abnormal B lymphocytes and do not become healthy white blood cells. The abnormal lymphocytes may also be called leukemia cells. The lymphocytes are not able to fight infection very well. Also, as the number of lymphocytes increases in the blood and bone marrow, there is less room for healthy white blood cells, red blood cells, and platelets. This may cause infection, anemia, and easy bleeding. 

How Common is CLL? 

CLL is one of the most common types of leukemia in adults. The average age of diagnosis is when people are in their late 60s. 

What are the Risk Factors for CLL? 

Most patients don't have a specific risk factor for CLL. Some characteristics that may be associated with CLL include: 

  • Being elderly, male, or white 
  • A family history of CLL or cancer of the lymph system 
  • Exposure to Agent Orange 

What are the Symptoms and Signs of CLL? 

Many people do not have any symptoms when they are diagnosed. CLL is often found when a doctor orders blood tests for an unrelated health problem. 

Symptoms can include: 

  • Weakness 
  • Feeling tired 
  • Unintentional weight loss 
  • Night sweats 
  • Enlarged lymph nodes (often felt as lumps under the skin) 
  • Pain or a sense of "fullness" in the belly (this can make someone feel full after only a small meal), which is caused by an enlarged spleen and/or liver 
  • Inability to fight serious infections well 

Growth and Spread 

CLL is a chronic (ongoing) disease that usually gets worse slowly. It often is present in the bone marrow, blood, and lymph nodes, and more rarely in organs. 

Precursor Conditions for CLL 

CLL is often preceded by a precursor condition, which is an early precancerous phase of blood diseases that may develop into cancer. Monoclonal B-cell lymphocytosis (MBL) is the common precursor condition to CLL. Most people who develop CLL have had MBL, and about 1 percent per year will convert to CLL. 

Our researchers in the Center for Early Detection and Interception of Blood Cancers (formerly the Center for Prevention of Progression) are studying the genomic, genetic, and epigenetic factors that characterize conditions that are often "precancerous." We aim to understand what changes cause MBL to progress to CLL so that we can prevent progression in the future. 

This research is driven by the center's PCROWD study, which collects, processes, and stores tissue samples from people with precursor conditions from across the United States. 

Find a list of drugs approved for chronic lymphocytic leukemia.

Why Choose Us

The Center for Chronic Lymphocytic Leukemia (CLL) at Dana-Farber Brigham Cancer Center provides comprehensive care and promising new therapies to patients with CLL. 

As one of only a few dedicated CLL centers in the country, our team has unique expertise in caring for patients with CLL, including extensive prognostic testing, tissue banking, and access to cellular therapies including stem cell/bone marrow transplant program and CAR T-cell therapy, if necessary. 

We are a centralized hub for CLL research. Our team of laboratory and clinical-based investigators and physicians offers access to clinical trials of new, promising therapies. Our goal is to have a clinical trial option for patients at every stage of the disease. We offer clinical trials for newly diagnosed CLL, relapsed/refractory CLL, as well as Richter's syndrome, a condition where CLL turns into an aggressive form of lymphoma. 

Our center is part of Dana-Farber Brigham Cancer Center's Hematologic Oncology Treatment Center, one of the world's largest and most respected treatment centers for patients with disorders of the blood or bone marrow.  

We provide comprehensive services to patients with these cancers, including:  

  • Personalized treatment plans, ranging from standard supportive care to intensive chemotherapy for chronic leukemia 
  • Access to new therapies through clinical trials, some of which may not be available elsewhere 
  • Close collaboration with the experts in our Bone Marrow Transplantation Program at Dana-Farber Brigham Cancer Center, one of the largest and most experienced programs in the world 
  • Access to the latest diagnostics, such as molecular and genomic profiling, including the Rapid Heme Panel, which was developed by our scientists to rapidly detect key mutations that are important for developing timely treatment plans
  • Multidisciplinary care delivered by specialists from Dana-Farber Cancer Institute and Brigham and Women’s Hospital