Blood cancers affect the production and function of your blood cells. Most of these cancers start in your bone marrow where blood is produced. Stem cells in your bone marrow mature and develop into three types of blood cells: red blood cells, white blood cells, or platelets. In most blood cancers, the normal blood cell development process is interrupted by uncontrolled growth of an abnormal type of blood cell. These abnormal blood cells, or cancerous cells, prevent your blood from performing many of its functions, like fighting off infections or preventing serious bleeding.
There are three main types of blood cancers:
Leukemia, a type of cancer found in your blood and bone marrow, is caused by the rapid production of abnormal white blood cells. The high number of abnormal white blood cells are not able to fight infection, and they impair the ability of the bone marrow to produce red blood cells and platelets.
Lymphoma is a type of blood cancer that affects the lymphatic system, which removes excess fluids from your body and produces immune cells. Lymphocytes are a type of white blood cell that fight infection. Abnormal lymphocytes become lymphoma cells, which multiply and collect in your lymph nodes and other tissues. Over time, these cancerous cells impair your immune system.
Myeloma is a cancer of the plasma cells. Plasma cells are white blood cells that produce disease- and infection-fighting antibodies in your body. Myeloma cells prevent the normal production of antibodies, leaving your body's immune system weakened and susceptible to infection.
What is blood cancer?
There are three main groups of blood cancer: leukemia, lymphoma and myeloma
Blood cancer is an umbrella term for cancers that affect the blood, bone marrow and lymphatic system.
Unfortunately, blood cancer affects a large number of people.
There are three main groups of blood cancer: leukemia, lymphoma and myeloma. Some types are more common than others:
- Non-Hodgkin lymphoma
- Other types of blood cancer – such as myeloma – are less common.
Leukemia affects your white blood cells. These are an important, infection-fighting part of your immune system, made in your bone marrow.
If you have leukemia, you produce an abnormal number of immature white blood cells which ‘clog up’ your bone marrow and stop it making other blood cells vital for a balanced immune system and healthy blood.
Acute leukemia comes on suddenly, progresses quickly and needs to be treated urgently. Chronic leukemia develops more slowly, over months or years.
There are four main types of leukemia:
- Acute myeloid leukemia (AML)
- Acute lymphoblastic leukemia (ALL)
- Chronic myeloid leukemia (CML)
- Chronic lymphocytic leukemia (CLL)
- acute promyelocytic leukemia (APL)
- hairy cell leukemia (HCL)
- large granular lymphocytic leukemia (LGL)
- t-cell acute lymphoblastic leukemia (T-ALL)
- chronic myelomonocytic leukemia (CMML)
Lymphoma is a type of blood cancer that affects your lymphatic system, an important part of your immune system, which helps to protect your body from infection and disease.
If you have lymphoma it means you make too many lymphocytes, a type of white blood cell. Your lymphocytes also live longer than they should. This overload compromises your immune system.
Lymphoma can develop in many parts of your body, including your lymph nodes, bone marrow, blood, spleen and other organs.
The two main types of lymphoma are:
- Non-Hodgkin lymphoma (NHL)
- Hodgkin lymphoma(used to be called Hodgkin disease)
Myeloma (also called multiple myeloma) is a blood cancer of the plasma cells. Plasma cells are found in your bone marrow and produce antibodies, which help fight infection.
In myeloma, unusually large numbers of abnormal plasma cells gather in your bone marrow and stop it producing an important part of your immune system.
Myelodysplastic syndromes (MDS)
The myelodysplastic syndromes (MDS) are a group of blood disorders where a person’s bone marrow is not producing the correct amount and quality of blood cells. Red, white and platelet cells can be affected.
These problems lead to people with MDS feeling very tired, weak and bleeding or bruising more easily. There are different levels of severity of MDS, it’s not a type of leukemia but can sometimes lead to acute myeloid leukemia. MDS is rare – about 4 in every 100,000 people get MDS. It mainly affects older people, and is more common in people over 70 years old.
If you have low or intermediate risk MDS you may not need immediate treatment, but regular blood transfusions and medication can help. Some people with more severe MDS can have chemotherapy and a small number of people may need to have a stem cell transplant
Treatments for blood cancer
When it comes to deciding on the best treatment, it all depends what type of blood cancer you have, how advanced and aggressive it is and your general health. Your doctor will suggest the most effective course of treatment for you.
Common treatments are chemotherapy, radiotherapy and, in some cases, a stem cell or bone marrow transplant.
What is chemotherapy?
Chemotherapy involves taking drugs that destroy cancer cells, hopefully putting it into remission or significantly slowing down the progression of the disease.
There are many types of chemotherapy drugs and they work in different ways. Sometimes doctors will prescribe a single drug, but often they’ll recommend combining two or more because they often work better together. Chemotherapy can be used on its own, but it’s often combined with other treatments like radiotherapy. Chemotherapy is designed to attack cells that are growing and multiplying. That’s because cancer cells grow and multiply faster than healthy cells.
Some healthy cells can be caught in the crossfire, as they can also be growing and dividing quickly. This can cause side effects such as nausea, tiredness and hair loss.
If you’re getting ready for a stem cell, bone marrow or cord blood transplant, you’ll also need chemotherapy to suppress your immune system and stop it attacking your donor’s new ‘foreign’ cells. This is called conditioning therapy.
What is radiotherapy?
Radiotherapy works by using high-energy X-rays to kill cancer cells.
For it to be effective, doctors need to give just the right amount of radiation, targeted at the right area of the body. That’s why you get radiotherapy in specialist centers where doctors, physicists and radiographers work together. They’ll normally use a machine called a ‘linear accelerator’ for the treatment.
Radiotherapy can treat some types of leukemia and lymphoma. Doctors can also use it to prepare a patient for a stem cell, bone marrow or cord blood transplant as part of the conditioning therapy. A low dose of radiation will lower someone’s immune system, so they’re less likely to reject donor cells. The type of radiotherapy you might have before a stem cell transplant is called total body irradiation or TBI and this means it affects the whole body.
Radiotherapy can also damage normal cells, which can cause side effects. These vary greatly for each person; some experiencing mild symptoms such as tiredness while for others it can be more debilitating. These side effects will normally have passed within a few weeks of the treatment finishing.
When radiotherapy finishes, most of your body's healthy cells will continue to grow normally again. But radiotherapy can have long-term side effects.