Myeloma - tests and investigations

What tests and investigations will I have?

Tests and investigations are carried out to:

• Establish a diagnosis
• Help determine a treatment plan and monitor progress
• Detect complications of the myeloma so that they can be treated
• Identify when relapse is occurring

There are three main tests carried out in myeloma patients:

• A bone marrow biopsy: to determine if there are abnormal plasma cells (myeloma cells) in the bone marrow. It can also be carried out once a course of treatment such as a stem cell transplant has finished to determine response to treatment as well as a suspected relapse to confirm the myeloma is becoming active again
• Blood and urine tests: to detect abnormal protein (paraprotein) which is being produced by the myeloma cells. This is done again to establish the diagnosis and to monitor response to treatment and confirm any suspected relapse
• X-rays: to look for evidence of myeloma bone disease. A skeletal survey is performed at diagnosis to determine the extent of any bone disease

What is a skeletal survey?

This is a series of X-rays of all the long bones and the skull and is used to detect any bone damage caused by myeloma. It is often one of the first tests to be carried out and can assist in confirming the diagnosis of myeloma.

Why is it done?

A skeletal survey is useful at diagnosis to detect the extent of any myeloma bone damage and can give the doctor an overall picture of a patient’s individual myeloma.

One-off X-rays can be requested at any time, if there is new or increasing pain in an area, in order to detect any new damage. Generally X-rays are good enough to highlight any area of bone disease caused by myeloma. If there is ever any doubt then the doctor may order more sophisticated scans (such as MRI or CT scans) of an area causing concern. These scans can provide more detail and can often identify areas of bone damage not seen on the X-ray.

What are the potential side-effects of X-rays?

X-rays cause no side-effects and exposure to radiation is minimal even with a full skeletal survey. However, the ovaries and testicles are particularly sensitive to radiation and therefore lead blocks are used to shield them if they are in the X-ray field.

What is an MRI?

MRI is an abbreviation for Magnetic Resonance Imaging and is a sophisticated scan which uses a magnetic field rather than X-rays to obtain clear pictures of bones or soft tissue. A dye is sometimes injected before the MRI to improve the quality of the image. The procedure involves lying on a bed which moves through a tunnel-like scanner.

Why is it done?

MRI is often used to identify lesions in areas which are causing symptoms but no damage has shown up on X-rays.

What are the potential side-effects of an MRI?

MRI is generally a very safe procedure but allergic reactions to the dye do sometimes occur. As a very strong magnetic field is used, all metal such as earrings and other jewellery should be removed. MRI cannot be used on patients who have pacemakers fitted or who have had surgery using metal implants to repair fractures.

The machine can be very noisy and headphones or earplugs are often offered.

What is a CT scan?

CT is an abbreviation for Computed (or Computerised) Tomography and uses computers and X-rays to build up a 3D image of bones or soft tissue. The scanner looks like a large doughnut and patients lie on a bed which moves through the doughnut. There may be a whirring noise as the scan takes place. Sometimes a dye is used to improve the quality of the image and this is injected into a vein just prior to the scan.

Why is it done?

CT scans are used when a more detailed image of a particular area is required or to pinpoint areas when planning treatment such as radiotherapy, Percutaneous Vertebroplasty or Balloon Kyphoplasty.

What are the potential side-effects of a CT scan?

CT scans are generally safe but patients are exposed to more radiation than with X-rays so are used sparingly. Allergic reactions to the dye, if used, can sometimes occur but this is rare.

What is a FDG / PET scan?

FDG / PET is an abbreviation for fluoro-deoxyglucose positron emission tomography.

FDG / PET can pinpoint problematic areas which may be missed on X-rays. It involves a low-dose radioactive glucose material being injected, which builds up in areas where there is active bone remodelling (the process by which old bone is broken down and new bone is formed). In myeloma bone disease there is increased activity of osteoclasts (cells that break down bone), so the radioactive drug will collect in these areas highlighting where myeloma bone disease is present.

Why is it done?

A FDG / PET scan can be used to identify any damage caused by myeloma. It is also helpful for monitoring purposes in people with non-secretory myeloma who do not have any evidence of paraprotein.

What are the potential side-effects of FDG / PET?

There are generally no side-effects from a FDG / PET scan, and exposure to radiation is minimal. The amount of glucose used is miniscule and should have no adverse effects for patients with diabetes.

What is a full blood count?

A full blood count is a blood test to measure the levels of blood cells such as red cells (and the haemoglobin within them), white cells and platelets. The measurements are compared against a normal range of values.

Why is it done?

Both myeloma and some of the treatments for it can have an effect on the production of blood cells. A full blood count can be used alongside other tests to monitor response to treatment as well as stability or progression of the myeloma.

What are red blood cells?

Red blood cells (Erythrocytes) carry oxygen in the form of haemoglobin round the body.

What are white blood cells?

White blood cells (Leucocytes) are part of the immune system and help fight infection. There are five different types of white blood cell.

What are platelets?

Platelets are very small blood cells that help blood to clot normally.

What is a bone marrow biopsy?

Bone marrow is the spongy material in the middle of most bones where plasma cells are found. A bone marrow biopsy is a test to measure the number of plasma cells in a sample of bone marrow.

A bone marrow biopsy is a fairly invasive procedure and will be carried out by skilled specialists. It involves putting a needle into the bone (usually the hip or breast bone) to get a small sample of the bone marrow (this sample is sometimes called an aspirate); the procedure is carried out under a local anaesthetic with or without sedation.

This sample is then examined to count the number of plasma cells present in the bone marrow: normal bone marrow has less than 5% plasma cells; bone marrow in myeloma patients may have between 10% and 90% plasma cells. A better indication of the number of plasma cells is gained by doing a 'trephine biopsy', which means taking a small core of bone along with the marrow inside.

Why is it done?

Bone marrow biopsies are particularly used to help establish a diagnosis and may be used at certain times in the treatment of myeloma to determine a response to treatment or to confirm any suspected relapse.

What are the potential side-effects of a bone marrow biopsy?

There may be some pain or bruising at the site of the biopsy, some patients may need to take regular paracetamol for a day or so after. If sedation has been given then there may be some sleepiness for a while so driving won’t be allowed.