Q&A: Blood cancers
The questions below were raised - and answered by our expert consultants - at one of our regular GP Education Days
Dr Mike Potter, Head of Haemato-oncology Unit, with a patient
What is the aetiology of Lymphoma?
Lymphomas develop because of changes in the genes of a lymphocyte (a type of white blood cell). These changes alter how the cell grows and divides or may prevent it dying when it normally should do. Often more than one change happens in the genes before a lymphoma develops.
We now know a lot about the gene changes in different types of lymphoma. In most cases, however, no one really knows what makes the changes happen. This is probably because lymphomas are caused by lots of different things that each affect the genes in a small way. Scientists sometimes call this the ‘multi-hit theory’.
There are some things that are known to increase the risk of developing lymphoma (often called ‘risk factors’). They are not a cause on their own but include:
- problems with the immune system
- certain infections
- a close relative having lymphoma
- previous treatment for cancer
- getting older
Other things that have been studied that may be a contributory risk factor are chemicals (or certain jobs where people use chemicals) and lifestyle, including smoking, diet and obesity.
How do we diagnose Chronic Lymphoctic Leukaemia?
CLL can be diagnosed with a full blood count, where it shows an increase in lymphocytes. Specialist tests on these can confirm the diagnosis by distinguishing CLL lymphocytes from normal B cells or from other B cell diseases.
Is there any absolute level of the total white blood cell count or lymphocyte count that would indicate re-referral to haematology?
If the FBC showed a lymphocyte count persistently at >10 x 109/L then we would recommend a referral to haematology.
Is there any increase in risk of developing blood cancers in regular blood donors?
No, there is no evidence to show this.
What are the main types of leukaemia and who do they affect?
Leukaemia is cancer of the white blood cells, where the body produces 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 leukaemia comes on suddenly, progresses quickly and needs to be treated urgently. Chronic leukaemia develops more slowly, over months or years.
There are four main types:
- Acute myeloid leukaemia (AML). This affects around 2,900 adults a year in the UK. It’s most common in people over 70, although people of any age can get it
- Acute lymphoblastic leukaemia (ALL). This is the most common type of leukaemia in children. ALL affects around 800 people a year in the UK. About half the cases are in adults and half in children. ALL has B & T cell types
- Chronic myeloid leukaemia (CML). This is also quite a rare condition: only about 700 people every year are affected
- Chronic lymphocytic leukaemia (CLL). Doctors diagnose just over 3,400 people with CLL a year in the UK. It’s more common if you’re over 60 and is very rare in people under 40.
Other types of leukaemia include:
- Acute promyelocytic leukaemia (APL)
- Hairy cell leukaemia (HCL)
- Large granular lymphocytic leukaemia (LGL)
- Chronic myelomonocytic leukaemia (CMML).
What are ‘B symptoms’ of blood cancers?
B symptoms refer to key indicators of Hodgkin's or non-Hodgkin’s lymphomas which reflects the staging of the cancer. They include fever, night sweats and unexplained weight loss.
The presence of these alongside other symptoms such as lymphadenopathy, splenomegaly, requires an urgent 2ww referral to a haematologist.
What is the difference between Small Lymphocyctic Leukaemia and Chronic Lymphocyctic Leukaemia?
This is the same disease biologically. Clinically, SLL presents with enlarged lymph nodes which may not initially be accompanied by any changes in the blood count. The BM is usually involved and, eventually, usually the blood as well. CLL will always present with evidence of the disease in the PB, but patients may also have lymphadenopathy.