Overview
Multiple myeloma refers to cancer of plasma cells, which are a type of white blood cell that produce antibodies. In patients with multiple myeloma, the cancerous plasma cells gather in the bone marrow, which affects the production of normal blood cells. It accounts for 1% of all cancers and 10% of haematologic cancers, meaning cancers that affect blood, bone marrow and lymph nodes. Multiple myeloma is more common in older patients, with 70% of patients diagnosed aged 50-70 years old, and is twice as common in men as in women.
The condition may develop in one of four ways. Some patients have multiple lesions on the bones in their head and trunk. Others find they have a lower bone density than normal. Multiple myeloma may also present as a single large lesion in the spine or pelvis or as a bone hardening or increasing in density.
Symptoms
Patients with multiple myeloma may experience a range of symptoms. Some patients experience hardly any symptoms, while others have severe symptoms that require emergency treatment.
The main symptom of the condition is bone pain, which at first only occurs intermittently but then becomes constant. The pain tends to be worse during the day, especially after activity or weight bearing. Other symptoms include decreased red blood cell count (anaemia), kidney failure, too much protein in the urine and too much calcium in the blood.
Patients may also experience complications related to the multiple myeloma, such as bone fractures, amyloidosis (the build-up of proteins in tissues and organs), recurrent infections, tumours made up of plasma cells and nerve damage.
Diagnosis
Multiple myeloma is often diagnosed after routine blood tests for other conditions, though a bone marrow biopsy or sample of cells is necessary to confirm the diagnosis.
It is essential for patients to have a skeletal survey (a series of X-rays of all the bones in the body), as this can be used not only to diagnose the extent of the disease but also to assess the patient’s response to treatment and predict potential complications such as fractures.
Other imaging techniques can be used to gather further information about the condition. MRI can be used to detect multiple lesions, while CT may be used to evaluate the soft tissue component outside the bone or the risk of fracture in severely affected bones. In order for your doctor to diagnose you as accurately as possible, a number of factors are needed, including physical examination, medical history, symptoms and lab results.
Treatment
Although multiple myeloma currently remains incurable, there are a number of treatments which may extend the patient’s life. Chemotherapy can be used to slow the progression of the disease and reduce symptoms, and drugs called bisphosphonates prevent the loss of bone mass and promote bone healing. If you experience anaemia, you may be treated with erythropoietin, which is a hormone that stimulates red blood cell production.
A further possible treatment is stem-cell harvest, which can then be used to give you a stem cell transplant after you have undergone bone marrow ablation using chemotherapy or radiotherapy. This approach has had positive results for response and disease-free survival rates.
Multiple myeloma is very sensitive to radiation, which is used to treat lesions that are causing discomfort or pain, stabilising bones at risk of fracture and treating problems with the spinal cord.
There are a number of minimally invasive techniques available, including vertebral and bone augmentation techniques, in which cement is injected into the area surrounding a fracture to stabilise it, reducing pain and improving mobility. Ablation techniques, in which the tumour cells are destroyed under imaging, can be used to control individual tumours.