CLL is treated when the disease is in the intermediate to advanced stages
Chronic lymphocytic leukemia (CLL) is slow-growing leukemia that progresses over many years. Many patients in the early stages of CLL do not have any symptoms and do not require immediate treatment. The disease is monitored regularly, and treatment is started when CLL progresses to the intermediate and advanced stages.
Stages of chronic lymphocytic leukemia
The spread of CLL is staged based on the enlargement of lymph nodes and other organs, as well as the effect on red blood cells and platelets. All stages of CLL have lymphocytosis or a high lymphocyte count.
CLL is commonly staged using the Rai 5-stage staging system:
- Stage 0: No symptoms and more than 5000 lymphocytes per microliter of blood.
- Stage I: Lymphocytosis and enlarged lymph nodes.
- Stage II: Lymphocytosis, swollen lymph nodes and enlarged liver and/or spleen.
- Stage III: Anemia, lymphocytosis, swollen lymph nodes and enlarged liver and/or spleen.
- Stage IV: Low platelet count, lymphocytosis, anemia, swollen lymph nodes and enlarged liver and/or spleen.
Stage 0 is considered the early stage or low-risk stage. Stages I and II are considered intermediate stages. Stages III and IV are considered advanced stages where CLL progresses rapidly.
How is CLL treated?
Treatment options for patients who have intermediate or advanced stages of CLL include:
- Chemotherapy: Cancer cells are destroyed using a combination of two or more drugs.
- Targeted cancer drugs: Uses drugs that identify and attack specific cancer cells. Tyrosine kinase inhibitor (TKI) therapy, BCL2 inhibitor therapy and monoclonal antibody therapy are examples of targeted therapies used to treat CLL.
- Immunotherapy: Uses special medications to activate the patient’s immune system to recognize and destroy cancer cells. Immuno-modulating agent lenalidomide and Chimeric antigen receptor (CAR) T-cell therapy are used to treat CLL.
- Radiotherapy: High-energy beams are used to destroy cancer cells, shrink swollen lymph nodes or spleen.
- Stem cell or bone marrow transplants: After destroying the patient’s stem cells using strong chemotherapy medications, healthy stem cells from a donor are transplanted into the patient. The transplanted stem cells start producing healthy blood cells in the patient’s body.
- Leukapheresis: Blood is passed through a special machine to lower the high number of CLL cells by filtering them out. This treatment is used as a temporary fix. Chemotherapy or immunotherapy is required to destroy the cancer cells.
- Surgery: If chemotherapy or radiation does not shrink an enlarged spleen, surgery may be performed to remove it.
What are the types of leukemia?
Leukemia is cancer of the white blood cells of the bone marrow, which is the spongy part in the center of the long bones. Patients with leukemia have an overproduction of the white blood cells (cells that fight infection and provide immunity) in the body.
Based on the origin, leukemia can be divided into two broad types:
- Myeloid leukemia (myelogenous leukemia) arises from the uncontrolled production of the blood cells called myeloblasts in the bone marrow. Normally, myeloblasts would turn into neutrophils.
- Lymphoid leukemia (lymphocytic or lymphoblastic leukemia) arises from cells called lymphoblasts in the bone marrow. Normally, lymphoblasts would turn into a particular type of white blood cells, the lymphocytes.
Based on how fast it progresses, leukemia is classified as acute or chronic:
- Acute leukemia: Most of the abnormal blood cells are immature and do not function normally. It progresses very quickly.
- Chronic leukemia: There are some immature cells, but others are normal and function normally. It progresses slowly.
What is chronic lymphocytic leukemia?
CLL is the most common type of leukemia in adults. In CLL, the bone marrow produces too many functionally incompetent lymphocytes. These abnormal cells compete with healthy cells for oxygen and nutrition, eventually starving and killing healthy cells. Over time, this causes an increased risk of infections, persistent tiredness, swollen glands in the neck, armpits or groin and unusual bleeding or bruising.
Basic characteristics of CLL are as follows:
- The disease mostly affects people over 60 years of age and is rarely found in people under 40 years of age.
- It progresses slowly compared with other types of blood cancers. Patients with CLL do not need drug therapy until they become symptomatic or show evidence of rapid progression of the disease.
- Although CLL cannot be cured completely, treatment can help control the condition for many years. CLL has a relatively higher survival rate than that of many other cancers.
- The 5-year survival rate for CLL is around 83%. For people over 75 years of age, the 5-year survival rate drops to less than 70%.
What are signs and symptoms of CLL?
Patients with CLL often do not present any signs or symptoms in the early stages, and the cancer is usually discovered when a blood test is done for a different health condition.
Symptoms of CLL may include:
- Painless swollen lymph nodes in the neck, groin or armpits due to lymphocyte accumulation
- Abdominal fullness, swelling and pain due to enlarged spleen
- Anemia and pale skin due to reduced red blood cells
- Bleeding and bruising, which occur more easily due to extremely low platelet count
- Petechiae, which are flat, dark-red spots under the skin caused by intradermal bleeding
- Shortness of breath
- Fever
- Fatigue
- Loss of appetite
- Unintentional or unexplained weight loss
- Recurrent infections
- Drenching night sweats
What causes CLL?
The exact cause of CLL is unknown. CLL results from genetic mutations (changes) of the stem cells in the bone marrow. While the exact cause of mutations is also unknown, potential causes include:
- Inherited chromosomal abnormalities; the deletions of parts on the chromosomes 11q, 13q, 17p and trisomy 12 have been seen in around 70-80% of CLL cases.
- First-degree relatives of patients with blood cancers.
- Exposure to certain chemicals (industrial solvents), such as benzene and butadiene.
- Prior chemo or radiation for cancer treatment.
- Underlying blood disorders, such as myelodysplastic disorders, Hodgkin lymphoma, Richter syndrome and hairy cell leukemia.