Leukemia is a general term for cancers affecting the blood and the blood-forming tissues of the body. Chronic Lymphocytic Leukemia (CLL) is the most prevalent form of the disease, with the majority of cases occurring in individuals aged 55 and over.
Like all types of leukemia, CLL begins with abnormalities in the creation of blood cells. Blood cells are primarily produced in the bone marrow, where immature stem cells develop into either lymphoid or myeloid stem cells.
Lymphoid stem cells mature into lymphocytes (B cells and T cells), which are crucial for the immune system. Myeloid stem cells mature into other white blood cells (monocytes and granulocytes), red blood cells (which carry oxygen), and platelets (which help blood to clot).
CLL develops from B cells. A cancerous B cell grows and multiplies abnormally in the bone marrow, lymph nodes, liver, and spleen, leading to a high white blood cell count. These cancerous cells are unable to function correctly to fight infection. They also crowd out healthy cells in the marrow and can cause the enlargement of the lymph nodes, liver, and spleen.
CLL is a chronic disease, meaning it is typically slow-growing and less aggressive than acute forms of leukemia. The presence of specific genetic mutations or proteins, however, can significantly affect a patient's outlook.
A risk factor is anything that increases the likelihood of developing a disease, though not all individuals with risk factors will develop the condition. Risk factors for CLL include:
Almost 90% of new CLL cases are diagnosed in people aged 55 and older.
More men develop CLL than women.
Having a parent, sibling, or child with CLL increases one's risk.
Exposure to Agent Orange is a known risk factor for CLL.
As chronic leukemia develops slowly, many CLL patients may not experience symptoms for months or even years. In such cases, the disease is often discovered incidentally through a routine blood test.
When symptoms do develop, they are frequently related to a deficiency of properly functioning blood cells, which impacts the body's ability to transport oxygen, fight infection, and stop bleeding. Symptoms can also be caused by low levels of haemoglobin.
Weakness, tiredness, and fatigue (often caused by the leukemia or low haemoglobin).
Fever and frequent infections (due to low counts of healthy white blood cells).
Excessive sweating or night sweats.
Easy bleeding and bruising, including bleeding of the gums (due to low platelet levels).
Recurrent nose bleeds.
Petechiae (a rash-like collection of pinpoint spots on the skin caused by bleeding into the skin, also due to low platelet levels).
Shortness of breath (may be due to low haemoglobin levels or lung infections).
Swollen lymph nodes (in the neck, underarm, stomach, or groin).
Loss of appetite or a feeling of fullness after eating very little (due to enlargement of the spleen).
Unexplained weight loss.
Bone and joint pain.
For female patients, longer or heavier than normal menstruation.
A successful treatment journey begins with an accurate and precise diagnosis.
Diagnosis typically starts with a simple blood test called a Complete Blood Count (CBC), which a doctor may order after evaluating a patient's symptoms or as part of a routine check-up.
If the CBC shows evidence of leukemia cells or abnormal levels of red blood cells, white blood cells, or platelets, doctors may order further tests to provide a definitive diagnosis, determine the extent of the disease, and monitor its progress.
This is a key diagnostic test for leukemia. It involves using a needle to take a sample of bone marrow from the hip to check for the presence of cancerous cells.
If leukemia is diagnosed, additional tests can determine if specific chromosomes or gene mutations are present in the diseased cells, or if the cells have particular proteins or molecules on their surface. This profiling helps doctors determine the exact type of leukemia and the patient's prognosis, informing the creation of the most effective treatment plan.
While leukemia starts in the bone marrow, it may spread to the central nervous system (brain and spinal cord). A lumbar puncture is used to examine the patient's spinal fluid for this spread. During this procedure, a small dose of chemotherapy may also be administered into the spinal fluid to kill any leukemia cells that may be present.
Doctors may order various imaging exams to look for the presence of cancer in other parts of the body.
Staging is the process of learning how far the cancer has spread within the patient's body, which is vital for determining prognosis and treatment plans. CLL is typically staged as follows (based on the National Cancer Institute system):
Too many lymphocytes are present in the blood, but there are no other signs or symptoms of leukemia. This stage is considered indolent (slow-growing).
Too many lymphocytes in the blood, and the lymph nodes are larger than normal.
Too many lymphocytes in the blood, and the liver or spleen is larger than normal. Lymph nodes may also be larger than normal.
Too many lymphocytes in the blood, and there is a low level of red blood cells (anaemia). The lymph nodes, liver, or spleen may be enlarged.
Too many lymphocytes in the blood, and there is a low level of platelets (thrombocytopenia). The lymph nodes, liver, or spleen may be enlarged, or there may be too few red blood cells.
The ultimate goal of leukemia treatment is to achieve remission and, where possible, a cure. Complete remission generally means that a patient's bone marrow has no detectable microscopic evidence of the disease and their blood counts have returned to normal. Patients who remain in continuous complete remission for an extended period are considered cured, having an extremely low chance of recurrence.
Clinical studies have often not demonstrated a benefit to immediate treatment for many early-stage CLL patients. Because of this, doctors frequently recommend active surveillance.
Patients undergo regular blood tests to monitor the disease's progress, specifically watching for an increase in leukemia cell count and a decrease in haemoglobin and platelet counts. Symptoms are managed as they arise.
If and when the disease progresses to a set point (known as an indication for treatment), initial therapies can include targeted therapy and a combined chemotherapy/immunotherapy treatment.
These initial treatments generally put patients into remission. Some may require continued maintenance therapy to sustain remission, while others may stop treatment entirely. All CLL patients in remission carry a risk of recurrence, which may necessitate further courses of treatment, including new drug combinations or a stem cell transplant.
Drugs used to kill cancer cells, control their growth, or alleviate disease-related symptoms. It may involve a single drug or a combination, depending on the cancer type and its rate of growth.
Drugs specifically designed to interfere with the molecules (often proteins) that cancer cells need to survive, multiply, and spread.
A procedure that replaces cancerous bone marrow with new, healthy bone marrow stem cells. This is typically done after intense chemotherapy to prepare the body. This physically challenging treatment is generally reserved for patients whose leukemia has returned, has not responded to standard treatments, or who have a high-risk form of the disease that makes a cure unlikely with standard therapies.
As a leading cancer centre, SSCHRC offers multiple clinical trials for CLL. These trials explore new drugs and drug combinations, including targeted therapies and immunotherapies.