(Information below courtesy of ALLG)
Leukaemia is a cancer that affects the blood and bone marrow where blood cells are made. All leukaemia starts in the bone marrow where developing blood cells, usually developing white cells, undergo a malignant (cancerous) change. This means that they multiply in an uncontrolled way, crowding the marrow and interfering with normal blood cell production. Increasing numbers of abnormal cells, called blast cells or leukaemic blasts eventually spill out of the bone marrow and travel around the body in the bloodstream. In some cases these abnormal cells accumulate in various organs including the lymph nodes, spleen, liver and central nervous system (brain and spinal cord).
While the number of abnormal cells in the blood is increasing, the number of normal red and white blood cells and platelets is decreasing. This means the remaining red blood cells cannot transport as much oxygen to the body’s tissues and organs; the normal white blood cells cannot effectively fight infection; and the platelets cannot ‘plug’ all the ‘leaks’ in the blood vessels. The leukaemia patient may therefore experience some of the symptoms or signs of particular blood cell shortages. For example, red blood cell loss would lead to fatigue and pallor (anaemia), white blood cell loss would lead to repeated infections, and platelet loss would lead to red skin blotches, numerous bruises, and nosebleeds. This explains why leukaemia results in anaemia, bleeding and infections.
Types of Leukaemia
Leukaemia is subdivided into a variety of large groups. The first division is between its acute and chronic forms:
Acute leukaemia is characterized by a rapid increase in the number of immature blood cells. Crowding due to such cells makes the bone marrow unable to produce healthy blood cells. Immediate treatment is required due to the rapid progression and accumulation of the malignant cells, which then spill over into the bloodstream and spread to other organs of the body.
Chronic leukaemia is characterized by the excessive build up of relatively mature, but still abnormal, white blood cells. Chronic leukaemia develop more slowly and may not need to be treated for some time after they are diagnosed.
Combining these two classifications provides a total of four main categories.
- Acute myeloid leukaemia (AML)
- Acute lymphoblastic leukaemia (ALL)
- Chronic myeloid leukaemia (CML)
- Chronic lymphocytic leukaemia (CLL)
- blood cancer affecting white blood cells
- develops in the lymphatic system
Lymphoma is a general term for cancer of the lymphatic system. The lymphatic system is part of the body’s immune system which protects against disease/infection and it is a network of vessels that run throughout the body, similar to blood vessels. These vessels carry colourless liquid called lymph, which circulates nutrients, waste and white blood cells around the body.
Lymphoma arises when developing lymphocytes (a type of white blood cell) undergo a malignant (cancerous) change and multiply in an uncontrolled way. The big problem is that these cells start to divide before they are fully mature. This means they can’t fight infection as normal white blood cells do. Another problem is that the abnormal lymphocytes start to collect in the lymph nodes (located in all parts of the body, but most easily found in the neck, armpit and groin) or in other parts of the body such as the bone marrow, spleen or other organs. These collections of lymphoma cells can grow into tumours and begin to cause problems within the lymphatic system or the organ in which they are growing. For example, if a lymphoma starts in the thyroid gland it can affect the normal production of thyroid hormones. Over time, lymphoma cells replace normal lymphocytes, weakening the immune system’s ability to fight infection.
Types of Lymphoma
There are many different sub-types of lymphoma, which are divided into two main types. The two types of lymphoma spread differently and are treated differently.
- Hodgkin lymphoma: This is a rare form of lymphoma characterised by a particular abnormal tumour cell – Reed Sternberg – not present in other forms of lymphoma.
- non-Hodgkin lymphoma (NHL): Any lymphoma that is not Hodgkin lymphoma is classified as non-Hodgkin lymphoma. There are more than 30 different subtypes of non-Hodgkin lymphoma, which are generally classified into two equal groups, depending on the rate at which the tumour is growing.
- Indolent (low-grade): Tumour cells divide and multiply slowly making initial diagnosis difficult. Patients may live many years with the disease, yet standard treatment cannot cure the disease in its advanced stages.
- Aggressive (intermediate/high grade): Tumour cells divide and multiply rapidly in the body and, if left untreated, can be fatal within four weeks to two years. Unlike indolent NHL, treatment of aggressive NHL can lead to patients being cured.
Myeloma, also known as multiple myeloma, is a cancer of plasma cells (a type of blood cell) that arises in the bone marrow (the soft tissue inside bones where blood cells are made).The plasma cells in healthy people are an important part of the immune system and develop from white blood cells called lymphocytes. These cells make antibodies that help fight infections.When a person has multiple myeloma, there is a large increase in the malignant (cancerous) plasma cells and a reduction in the normal cells. The malignant plasma cells are inside the bone marrow. This means that there is no longer the space necessary to make normal white cells, red cells and platelets.As a result, the person has fewer red and white cells. The low red cell count causes anaemia (with symptoms such as tiredness, lethargy and shortness of breath on exertion). The low white cell count may mean the person is less able to fight infections.
Multiple myeloma spreads from the bone marrow into the bone. The malignant plasma cells produce different substances that cause the bone to become thin, weak and more likely to break. This may be associated with an increase in the level of calcium in the blood (hypercalcaemia). Abnormal proteins produced by the malignant cells may affect the kidneys so that they cannot filter and clean the blood properly.
Symptoms of Myeloma;
- Bone lesions leading to pain and fractures;
- Anaemia and fatigue;
- Kidney damage leading to renal failure &
- Recurrent and /or persistent infections