Multiple myeloma

Multiple myeloma is a type of blood cancer that originates due to an abnormal proliferation of plasma cells (one type of leukocyte, the body’s defence). These plasma cells can cause bone lesions, growing profusely and causing anaemia. At the same time, they are able to produce immunoglobulins. These are proteins that, in excess, can affect the kidneys and increase the risk of infection.

Multiple myeloma is a type of bone marrow cancer that comes about due to the proliferation of clonal plasma cells and the abnormal production of immunoglobulins (Ig), which are a component of the immune system and can be found in blood and/or urine.

Description

The annual incidence in adults is 4-6 new cases per 100,000 of the population per year, which represents 1% of all cancers and 10% of blood cancers. These figures mean the condition is considered rare. It often affects predominantly older people, with the average being around 70 years.

What happens when someone has multiple myeloma?

Excess Ig interferes with the properties of the blood, affecting normal kidney function and increasing the risk of developing infections (as normal Ig are not produced). If there are also excess plasma cells, the bones containing bone marrow may be damaged, with possible fractures and pain. It can also make the normal production of red blood cells, white blood cells and platelets more difficult, leading to increased risk of anaemia, infection and bleeding.

The symptoms

The classic symptoms of myeloma are given by the initials of the affected organs: “CRAB” (Calcium, Renal failure, Anaemia, Bone lesions). These may, however, lead to other symptoms:

Anaemia (most common symptom): tiredness, weakness, sickness, drowsiness
Fever, infection
Bleeding
Peripheral neuropathy, shivers, cold hands and feet
Bone pain
Renal failure: oedema/swelling, decreased urination/non-passage of urine
Organ failure due to protein deposits in different organs
Skin outbreak
Constipation, diarrhoea

Diagnosis

In a routine analysis, it is common to find a monoclonal gammopathy, anaemia or to diagnose a fracture after the persistence of bone pain that does not stop with conventional analgesia.

To confirm the diagnosis and establish the extent and treatment needs, a full blood count needs to be conducted with a special protein study, a urine analysis to rule out abnormal protein excretion by the kidneys, a bone marrow aspirate or biopsy to confirm excess plasma cells in the bone marrow (if possible with cytometric and genetic study) and imaging tests to rule out bone lesions.

Typical treatment

Treatment of multiple myeloma has changed significantly in the last decade and above all in recent years with the appearance of new drugs and action mechanisms.

The aim of treatment is to control the condition for the longest amount of time possible with minimal side effects and to achieve a good quality of life.

Treatment of multiple myeloma includes drugs that can be classified according to their mechanism of action:

· Proteaosome inhibitors

· IMiDs

· Alkylating agents

· Corticosteroids

· Monoclonal antibodies

As well as the drugs and combinations used, a treatment plan may also take into account the possibility of one (or two) bone marrow transplants.

There is currently an exponential increase in the development of new treatments for multiple myeloma. New drugs are being developed with different mechanisms of action. In some cases, these new drugs or potentially beneficial combinations may be offered as part of clinical trials.