Article written by
Kelly Crumrin

Oncologists (doctors specializing in cancer) assign a stage to multiple myeloma as a way of expressing how advanced the cancer is and their prediction for how it will progress. Recommendations about myeloma treatment are based partly on the stage. Two different systems are used to stage multiple myeloma. Both systems recognize three stages and are based on the results of clinical tests rather than myeloma symptoms a person experiences.

Some doctors regard related precancerous conditions such as monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) as early, asymptomatic stages of multiple myeloma. However, this article deals with how cancer is staged when multiple myeloma is first diagnosed or when it relapses. Read more about myeloma types and related disorders.

Systems for staging multiple myeloma

The two staging systems for multiple myeloma are based on measurements of different properties.

International Staging System (ISS)

The International Staging System was introduced in 2003, and many doctors consider it a more accurate assessment of the risk for multiple myeloma progression. The ISS does not take X-rays or bone lesions into account when staging multiple myeloma. Oncologists using the ISS perform a cytogenic study to examine the genes of cancer cells for traits connected with a high risk for progression. They also measure levels of different substances found in the blood:

Albumin – A common protein
Beta microglobulin – Protein produced by myeloma cells
Lactate dehydrogenase – Enzyme produced as cells turn glucose into energy

Stage I

• Cytogenic studies do not show high risk for progression
• Albumin levels greater than 3.5 grams per deciliter
• Beta macroglobulin levels less than 3.5 milligrams per liter
• Normal lactate dehydrogenase levels

Stage II

• Findings more advanced than stage I, but less advanced than stage III

Stage III

• Cytogenic studies show high risk for progression
• Beta macroglobulin levels greater than 5.5 milligrams per liter
• Elevated lactate dehydrogenase levels

Durie-Salmon Staging System

First introduced in the 1970s, the Durie-Salmon staging system is still used by some doctors to stage multiple myeloma. Oncologists using the Durie-Salmon system look at X-rays and count bone lesions as well as measuring levels of certain substances in the blood and urine:

Hemoglobin – a protein that transports oxygen in the blood
Calcium – a mineral released when bones are breaking down
M-proteins – abnormal fragments of antibodies made by the immune system
Light chains – abnormal fragments of antibodies made by the immune system

Stage I

• Normal X-rays or solitary plasmacytoma (one bone lesion)
• Hemoglobin greater than 10.5 grams per deciliter
• Blood calcium 12 milligrams per deciliter or less
• M-proteins, IgG less than 5 grams per deciliter, IgA less than 3 grams per deciliter
• Light chains in urine less than 4 grams in 24 hours

Stage II

• Findings more advanced than stage I, but less advanced than stage III
• Divided into stage IIA if there is no kidney failure, stage IIB if kidney failure is present

Stage III

• X-rays show more than three bone lesions
• Hemoglobin less than 8.5 grams per deciliter
• Blood calcium greater than 12 milligrams per deciliter
• M-proteins, IgG greater than 7 grams per deciliter, IgA greater than 5 grams per deciliter
• Light chains in urine greater than 12 grams in 24 hours

Re-staging

If there is a relapse after multiple myeloma has been effectively treated, the oncologist may re-stage the cancer based on the same criteria.

Resources

External references

• Myeloma Staging – Leukemia & Lymphoma Society
• Multiple Myeloma: Stages – Cancer.net

Internal resources

• Multiple Myeloma – An Overview
• Multiple Myeloma – The Path to Diagnosis
• Symptoms of Multiple Myeloma
• Treatments for Multiple Myeloma
• What Causes Multiple Myeloma?
• Myeloma Types and Related Conditions
• Myeloma Treatments A-Z

Kelly leads the creation of content that educates and empowers people with chronic illnesses. Learn more about her here.