Myeloma diagnosis and classification

Doctors will do many different tests to find out the type of the cancer and how much it has spread. Some tests may also help to define the best treatment options.

Myeloma diagnosis usually requires

  • blood and urine tests
  • imaging studies
  • bone marrow exams.

Bone marrow exams will be taken at the latest when the myeloma is causing symptoms and treatment is being planned.

Blood or urine samples are investigated for the abnormal protein produced by the malign plasma cells, i.e. paraprotein (M component), because it is almost always found in patients with myeloma. Paraprotein levels may be indicative of how extensive the disease is, and they can also be used to monitor the effectiveness of treatment.

Blood tests are also used to examine many other values such as red and white blood cell counts and
thrombocyte (platelet) values.

Imaging studies are used to find out what kind of changes the myeloma has caused in the skeleton.
X-ray images are taken of areas such as the skull, pelvis, arms and legs and the spine. Sometimes,
imaging is augmented with computed tomography, magnetic resonance imaging or PET scans.

Bone marrow examinations to confirm the diagnosis

Myeloma diagnosis is confirmed with a bone marrow examination consisting of

  • bone marrow aspiration
  • often also bone marrow biopsy.

Bone marrow aspiration biopsy may be taken from the breastbone (sternum), or the iliac crest in
the lower back. The skin around the biopsy site is numbed and a doctor will take the sample using a
special syringe. If necessary, a bone marrow biopsy may be taken from the back of the hip bone to
find out how many myeloma cells there are in the bone marrow.

The bone marrow samples show whether there is any impairment in the production of blood cells
and whether the number and appearance of plasma cells are abnormal. The existence of myeloma
cells confirms the diagnosis, and their proportion indicates how extensive the disease is.

Myeloma classification

Doctors define the stage and classification of the cancer based on the examination results. Myeloma
is classified based on blood tests into three “ISS risk classes” (International Staging System),
which are used to determine the prognosis. ISS stage 1 has the best prognosis and stage 3 the worst
prognosis.

Myeloma classification is important for deciding on an appropriate and effective treatment plan.