Multiple Myeloma Stages, Classification, and Risk
Multiple myeloma is a type of blood cancer that affects plasma cells. When you have multiple myeloma, your plasma cells change and grow faster than normal.
Multiple myeloma stages, classifications, and risk are based on the tests done at the time of diagnosis.
Staging in multiple myeloma is different from that in solid tumors, like breast cancer or lung cancer. Solid tumor staging reflects tumor size and spread. When a solid tumor has spread to other parts of the body, it is called metastatic. Multiple myeloma is a blood cancer that is always considered “metastatic” because it affects the blood and bone marrow.
Myeloma staging focuses on protein levels, kidney function, and bone damage. But it doesn’t predict patient outcomes in the same way that a solid tumor stage might. When you receive your diagnosed “stage,” remember that myeloma staging serves a different purpose and may not closely predict your prognosis.
What is the Revised International Staging System (R-ISS) for multiple myeloma?
The revised International Staging System (R-ISS), updated in 2015, was based on data from 4,445 newly diagnosed multiple myeloma patients across 11 clinical trials.
Myeloma experts were already aware that high beta-2 microglobulin and low albumin levels indicated higher-risk myeloma. The update incorporated new insights into high-risk genetic features and elevated LDH levels, which are now included in the staging system.
R-ISS Stage I
Criteria | Test Type | Results |
Beta 2 microglobulin | Blood | Less than 3.5 mg/L |
Albumin | Blood | Greater than 3.5 g/dL |
Genetics | Bone marrow biopsy | Standard-risk chromosomal abnormalities by FISH |
LDH | Blood | At or under normal LDH levels |
R-ISS Stage II (Neither Stage I nor Stage III)
Criteria | Test Type | Results |
Beta 2 microglobulin | Blood | Between 3.5 - 5.5 mg/L OR |
Albumin | Blood | Less than 3.5 g/dL |
R-ISS Stage III
Criteria | Test Type | Results |
Beta 2 microglobulin | Blood | Over 5.5 mg/L |
Albumin | Blood | Greater than 3.5 g/dL |
Genetics | Bone marrow biopsy | High risk chromosomal abnormalities including del 17p, translocation 4;14 or translocation 14;16 by FISH OR |
LDH | Blood | LDH over normal levels |
Learn how to understand myeloma staging with Dr. Muzaffar Qazilbash from MD Anderson Cancer Center
Characteristics of high-risk multiple myeloma
The International Myeloma Society/International Myeloma Working Group considers myeloma high risk if it features at least one of the following genetic changes or lab test results:
Del(17p) at more than 20% clonal fraction and/or a TP53 mutation
A translocation of t(4:14), t(14;16), or t(14;20) with 1q+ and/or del(1p32)
Monoallelic del(1p32) with 1q+ or biallelic del(1p32)
High levels of beta2-microglobulin (greater than or equal to 5.5 mg/L) with normal creatinine (less than 1.2 mg/dL)
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