Revised Multiple Myeloma International Staging System (R-ISS)
Why Use
Provides better discrimination of prognosis for MM by using simple, readily available variables. Reliable, validated tool that may have a role in upfront risk stratification in future clinical trials, and also may help patients understand their prognosis better.
When to Use
Newly diagnosed MM patients. Its utility has NOT been validated in relapsed myeloma, smoldering myeloma or MGUS patients.
Formula
Pearls / Pitfalls
The revised International Staging System (R-ISS) for multiple myeloma was developed to better prognosticate long term outcomes of myeloma patients using easily obtained and routinely used prognostic variables. It includes the parameters from the International Staging System (ISS), as well as cytogenetic abnormalities (CA) serum lactate dehydrogenase (LDH). The R-ISS creates 3 subgroups with significantly different overall survival: Stage I: 82% Stage II: 62% Stage III: 40% It risk-stratifies multiple myeloma patients better than the original ISS. 40% of patients in the data set were not transplant eligible, which reflects a more real-world population than does previous studies
Management
Current staging systems provide prognostic information and are useful for stratification and data assessments/comparisons. The R-ISS, though a more robust powerful prognostic tool compared to ISS, is NOT directly used to alter treatment recommendations outside of a clinical trial at this time.
Advice
Many MM patients are treated through clinical trials. Physicians may consider referring patients to academic treatment centers if they are eligible and willing to receive transplantation, not only to discuss standard treatment options, but also to consider clinical trial options.
More Information
R-ISS interpretation: R-ISS Stage Median progression-free survival I 66 months II 42 months III 29 months