Lymphocytic leukaemia is a type of blood cancer that affects white blood cells and bone marrow. While it can sound frightening, understanding this condition and the options available can help patients and families navigate the journey ahead with greater confidence and clarity.
Understanding Lymphocytic Leukaemia
Lymphocytic leukaemia is cancer that starts in the blood and bone marrow. The bone marrow is the spongy tissue inside your bones where blood cells are made. This type of cancer specifically affects lymphocytes, which are a kind of white blood cell that normally helps your body fight off infections. When you have lymphocytic leukaemia, your bone marrow produces too many abnormal lymphocytes that don’t work properly.[1]
There are two main forms of lymphocytic leukaemia: chronic and acute. Chronic lymphocytic leukaemia (CLL) develops slowly over time, while acute lymphocytic leukaemia (ALL) progresses much more quickly and creates immature blood cells rather than mature ones.[1][3] The word “chronic” refers to the slower progression of the disease, while “acute” indicates that the disease advances rapidly.[1][3]
In chronic lymphocytic leukaemia, the abnormal lymphocytes may also be called leukaemia cells. These cells cannot fight infection very well. As the number of leukaemia cells increases in your blood and bone marrow, there is less room for healthy white blood cells, red blood cells, and platelets. This crowding out of healthy cells can lead to infection, anaemia (a condition where you don’t have enough red blood cells), and easy bleeding.[6]
How Common Is Lymphocytic Leukaemia
Chronic lymphocytic leukaemia is one of the most common types of leukaemia in adults. It affects about 5 in every 100,000 people in the United States. Estimates suggest that around 18,700 people will be diagnosed with CLL each year.[2] By comparison, this is much less common than conditions like lung cancer, which affects more than 238,000 people annually.[2]
Acute lymphocytic leukaemia, on the other hand, is the most common type of cancer in children, and treatments offer a good chance for cure in younger patients. However, when ALL occurs in adults, the chance of cure is greatly reduced.[3]
Chronic lymphocytic leukaemia typically affects people aged 65 and older, though it can occur in people as young as 30. Most people are around 70 or 71 years old when they receive their diagnosis. The condition is more common in men than in women, particularly among white men.[2][4]
What Causes Lymphocytic Leukaemia
Lymphocytic leukaemia happens when bone marrow cells develop changes, known as mutations, in their genetic material or DNA. The DNA in a cell contains instructions that tell the cell what to do. Normally, these instructions tell the cell to grow at a set rate and to die at a set time. In leukaemia, the mutations tell the cells to keep growing and multiplying, and they don’t die when they should.[3]
Medical researchers know that chronic lymphocytic leukaemia is caused by these genetic changes that control the growth of bone marrow cells. However, the exact reason why these changes occur remains unknown.[4] Scientists have identified that these mutations happen during a person’s lifetime rather than being inherited from parents.[4]
The leukaemia cells continue to multiply and accumulate over time. In chronic lymphocytic leukaemia, this accumulation happens slowly, which is why the disease progresses gradually. These abnormal cells can spread beyond the blood and bone marrow to the lymph nodes, spleen, and liver.[4]
Risk Factors for Developing Lymphocytic Leukaemia
Several factors have been identified that may increase a person’s risk of developing lymphocytic leukaemia. Understanding these risk factors can help people be more aware, though having a risk factor doesn’t mean you will definitely develop the disease.
Age is one of the most significant risk factors. Chronic lymphocytic leukaemia most commonly affects people over the age of 50, with the average age at diagnosis being 70 years old.[4] The condition is quite rare in younger people.
Sex also plays a role. Men are more likely to develop CLL than women. This pattern is especially noticeable among white men, who have higher rates of the disease than other groups.[2][4]
Family history is another important consideration. Studies show that people with close relatives who have CLL, such as a biological parent, sibling, or child, are two to four times more likely to develop the condition themselves.[2] This suggests that genetic factors may play some role, even though the disease itself is not directly inherited.
Exposure to certain chemicals has been linked to chronic lymphocytic leukaemia. In particular, exposure to Agent Orange, a herbicide that was used during the Vietnam War, has been associated with an increased risk of developing CLL.[2][4]
There is also a condition called monoclonal B-cell lymphocytosis (MBL) that can increase risk. In this condition, you have a higher-than-normal number of identical B-cells (a type of lymphocyte) in your blood. If you have this condition, you may be at greater risk of developing chronic lymphocytic leukaemia.[2][4]
Symptoms of Lymphocytic Leukaemia
One of the challenging aspects of chronic lymphocytic leukaemia is that symptoms may not appear right away. Many people have no symptoms at all when they are first diagnosed. In fact, most people learn they have CLL after having blood tests done as part of routine physical examinations.[2][6] It may take months or even years before symptoms become noticeable.[2]
When symptoms do develop, they can include swollen lymph nodes. These swollen nodes might feel like lumps under the skin and happen most often in the neck, armpit, and groin areas. The swelling is usually painless.[1][6]
Fatigue is another common symptom. This overwhelming tiredness happens because CLL affects your red blood cells, causing anaemia. When you don’t have enough healthy red blood cells to carry oxygen throughout your body, you feel exhausted even after rest.[2][4]
Many people with chronic lymphocytic leukaemia experience fever and frequent infections. Because the disease affects the white blood cells that normally fight off germs, your body has a harder time protecting itself from bacteria and viruses.[1][4]
Night sweats that drench your bedding can occur. You might also experience unexplained weight loss, where you lose weight without trying or changing your diet.[1][4]
Some people feel pain or fullness in the upper left part of their belly. This happens when the spleen becomes enlarged due to cancerous white blood cells accumulating there.[1][4] Loss of appetite can also occur, making it difficult to maintain normal eating patterns.[1]
In more advanced cases, people may experience easy bruising or bleeding. You might also notice petechiae, which are flat, pinpoint, dark-red spots under the skin caused by bleeding. Weakness and a general decrease in energy are also possible symptoms.[3][6]
Prevention Strategies
Unfortunately, there are no known ways to prevent lymphocytic leukaemia because the exact causes remain unclear. Since the disease results from genetic mutations that happen during a person’s lifetime, and researchers don’t fully understand what triggers these changes, specific prevention measures cannot be recommended.[4]
However, people who know they have risk factors can be more vigilant about their health. Those with a family history of CLL or who have been exposed to Agent Orange should discuss their concerns with their doctor. Regular check-ups and blood tests can help detect the disease early if it develops.
Once diagnosed with chronic lymphocytic leukaemia, there are steps you can take to support your overall health and wellbeing. Maintaining a healthy lifestyle through balanced nutrition and appropriate physical activity, when possible, can help your body cope better with the disease and its treatments. Staying up to date with vaccinations to prevent infections is particularly important since CLL affects your immune system’s ability to fight off illnesses.[17]
How Lymphocytic Leukaemia Affects the Body
To understand how lymphocytic leukaemia affects your body, it helps to know how blood cells normally develop. Blood cells start as blood stem cells, which are immature cells in your bone marrow. Over time, these stem cells mature into different types of blood cells that your body needs.[6]
A blood stem cell can become either a myeloid stem cell or a lymphoid stem cell. Myeloid stem cells develop into red blood cells that carry oxygen, white blood cells called granulocytes that fight infection, or platelets that help your blood clot. Lymphoid stem cells become lymphocytes, which are white blood cells that play crucial roles in your immune system.[6][10]
There are three main types of lymphocytes. B lymphocytes (or B-cells) make antibodies to help fight infection. T lymphocytes (or T-cells) help B-cells make antibodies and can directly attack infected or cancerous cells. Natural killer cells attack cancer cells and viruses.[6][10]
In chronic lymphocytic leukaemia, too many blood stem cells become abnormal lymphocytes. Most cases of CLL affect B-cells, though there is a related condition called T-cell prolymphocytic leukaemia that affects T-cells.[2][4]
These leukaemia cells don’t function properly. They cannot effectively fight infections like healthy white blood cells would. Instead of dying when they should, they continue to accumulate in the blood, bone marrow, and lymphoid tissues.[6][7]
As more and more leukaemia cells build up, they crowd out the space needed for healthy blood cells. This means your bone marrow produces fewer healthy white blood cells, red blood cells, and platelets. The lack of healthy white blood cells increases your risk of infections. The shortage of red blood cells leads to anaemia, causing fatigue and weakness. Without enough platelets, you may bruise easily or have difficulty stopping bleeding.[6][10]
The leukaemia cells can also accumulate in your lymph nodes, causing them to swell. When they build up in your spleen or liver, these organs can become enlarged, which may cause pain or a feeling of fullness in your abdomen.[4]
Chronic lymphocytic leukaemia can also cause problems with your immune system beyond just reducing your ability to fight infections. Some people develop complications such as Coombs-positive haemolytic anaemia, where the immune system attacks red blood cells, or immune thrombocytopenia, where it attacks platelets. Levels of protective proteins called immunoglobulins may also become depressed, further weakening immune defences.[1][15]
The disease progresses from an initially mild increase in lymphocytes without other obvious problems to a more generalized condition with enlarged lymph nodes and low blood cell counts. Complications from low blood cell counts, including bleeding and serious infections, represent major challenges in managing this disease.[15]