Chronic Lymphocytic Leukemia (CLL)

Chronic lymphocytic leukemia is a type of blood, lymph node and bone marrow cancer in which too many abnormal white blood cells called lymphocytes accumulate in your body.

Chronic Lymphocytic Leukemia (CLL)

The Basics

Chronic lymphocytic leukemia (CLL) is a type of cancer that involves certain white blood cells (lymphocytes) that develop in the bone marrow and lymph nodes. These cancer cells then move into the bloodstream.

Cancer cells often build up slowly in CLL. Many people don't have any symptoms for the first few years. Over time, the cells can spread to other areas, such as the lymph nodes, liver and spleen.

CLL is one of the most common types of leukemia in adults and mainly affects older adults. The average age at diagnosis is around 71 years. It rarely occurs in people under age 40. Although CLL includes the word “leukemia” because abnormal cells are found in the blood, CLL is more similar to non-Hodgkin lymphoma than to the other leukemias.

According to the American Cancer Society, about 19,000 new cases of CLL are diagnosed in the U.S. each year.

Relation to bone marrow failure diseases:

CLL patients who are treated with certain types of chemotherapy have an increased risk of developing myelodysplastic syndromes (MDS).

Causes

The exact cause of CLL is not known. There are, however, a few known risk factors that increase the chances of getting CLL. They include:

  • Exposure to certain chemicals like Agent Orange and long-term exposure to some pesticides
  • Gender, since males are more likely than females to get CLL
  • A family history of CLL
  • Ethnicity, since CLL is more common in people of North American or European decent than people of Asian descent

Symptoms

Most people with CLL do not have any symptoms when diagnosed. The high lymphocyte count is often found during routine blood tests. Some symptoms reported by patients include:

  • Weakness
  • Feeling tired
  • Weight loss
  • Night sweats
  • Swelling of the lymph nodes in the neck, underarm, stomach, or groin
  • Pain or a feeling of fullness below the ribs
  • Fever and infection

As CLL becomes more advanced, the cancer cells can replace the bone marrow’s normal blood-making cells, which can cause the marrow to produce fewer red cells, white cells and platelets with these results:

  • A low number of red blood cells (anemia) can lead to feeling very tired, shortness of breath and pale skin.
  • A low number of normal white blood cells (leukopenia) can lead to a fever and frequent or severe infections.
  • A low number of blood platelets (thrombocytopenia) can lead to problems with easy bruising and bleeding. Some people have frequent or severe nosebleeds or bleeding from the gums.

Diagnosis

Doctors often discover CLL when doing routine blood tests for other reasons. For instance, a person's white blood cell count may be very high, even though he or she doesn't have any symptoms. Other tests that might be done to confirm diagnosis include:

  • Physical exam and history
  • Blood tests include:
    • Complete blood count with a differential looks at the total number and type of blood cells in your blood
    • A blood smear allows your doctor to look at your blood under a microscope
  • Bone marrow aspiration and biopsy to see howyour bone monocytes in your bone marrow look
  • Cytogenetic testing that looks at abnormalities in your cell DNA

Different kinds of CLL:

  • Some kinds of CLL grow slowly and patients don’t need treatment for a long time.
  • Other kinds of CLL are more serious because they grow much faster.

The leukemia cells from these 2 types look alike, but tests reveal their differences.

Treatment

Treatment depends on the stage of disease, how low the blood counts are, and symptoms like fever, chills, or weight loss, and whether the liver, spleen or lymph nodes are enlarged. The response to initial treatment and whether the CLL has recurred are also considered. Often no treatment is required for many years.

Treatment options include:

  • Supportive care with blood transfusions, blood cell growth factors and antibiotics to treat infections
  • to kill cells cancer cells
  • Monoclonal antibodies, man-made versions of immune proteins that attach to a specific target cell, help the immune system find and destroy the cancer cells. Rituximab, obinutuzumab and ofatumumab are used because they target the protein CD20 found on the surface of B lymphocytes.
  • Targeted therapies work in different ways to kill the CLL cancer cells and stop them from growing. Targeted therapies for CLL include Ibrutinib, idelalisib, venetoclax and others.

Clinical trials, also called research studies, may offer good treatment options for some CLL patients. These studies also help researchers better understand the value of promising new treatments or procedures.