Overview of Prognostic Systems

Prognostic systems aim at improving the ability to predict survival and progression in patients with myelodysplastic syndromes (MDS), based on the identification of independent predictive variables such as1,2:

  • Age
  • Peripheral cytopenias
  • Bone marrow (BM) blast count
  • Cytogenetic pattern

The evolution of prognostic systems

There are 5 validated prognostic scoring systems for MDS3-7:

CMML, chronic myelomonocytic leukemia; IPSS, International Prognostic Scoring System; IPSS-R, Revised International Prognostic Scoring System; MDA, MD Anderson; MDA LR-PSS, MD Anderson Lower-Risk Prognostic Scoring System; WPSS, World Health Organization (WHO) Prognostic Scoring System.

The International Prognostic Scoring System (IPSS) provides a means of calculating the prognosis for a patient with MDS based on the percentage of BM blasts, cytogenetic parameters (karyotype), and number of cytopenias.3

  • The IPSS has been validated in independent patient populations and has been shown to be effective in predicting the outcome of treatment after diagnosis, but it does not identify patients with lower-risk disease and poor prognosis7

The World Health Organization Prognostic Scoring System (WPSS) provides a means of calculating the prognosis for a patient with MDS based on their WHO subgroup, karyotype categorized according to IPSS, and degree of anemia.4

The Revised International Prognostic Scoring System (IPSS-R) is an update to the IPSS, providing a means of calculating the prognosis for a patient with MDS based on the same clinical features as those used in the IPSS, but employing a revised cytogenic scoring that includes 5 cytogenetic subgroups instead of 4.5 Also, new marrow blast categories were identified: 0 to ≤2%, >2% to <5%, 5% to 10%, and >10%.3

The MD Anderson General Risk Model (MDA General Risk Model) adapted the IPSS to include additional MDS subgroups (secondary MDS, chronic myelomonocytic leukemia [CMML]).6

The MD Anderson Lower-Risk Prognostic Scoring System (MDA LR-PPS) was proposed to further stratify IPSS lower-risk patients with MDS into 3 different risk groups.7

  • MD Anderson evaluated patients with low or intermediate-1 disease as determined by the IPSS and found the following were associated with worse survival7:
    • Low platelets (platelet count ≤200 x 109 cells/L)
    • Anemia (hemoglobin [Hb] <10 grams per deciliter [g/dL])
    • Older age (≥60 years)
    • Higher percentage of marrow blasts (≥4%)
    • Unfavorable cytogenetics (other than diploid and del[5q])
  • This indicates there is a possibility to identify lower-risk patients who may benefit from early therapy intervention7

References: 1. Invernizzi R, Filocco A. Myelodysplastic syndrome: classification and prognostic systems. Oncol Rev. 2010;4:25-33. 2. Malcovati L, Nimer SD. Myelodysplastic syndromes: diagnosis and staging. Cancer Control. 2008;15(suppl):4-13. 3. Greenberg P, Cox C, LeBeau MM, et al. International scoring system for evaluating prognosis in myelodysplastic syndromes. Blood. 1997;89(6):2079-2088. 4. Malcovati L, Della Porta MG, Strupp C, et al. Impact of the degree of anemia on the outcome of patients with myelodysplastic syndrome and its integration into the WHO classification-based Prognostic Scoring System (WPSS). Haematologica. 2011;96(10):1433-1440. 5. Greenberg PL, Tuechler H, Schanz J, et al. Revised International Prognostic Scoring System for myelodysplastic syndromes. Blood. 2012;120(12):2454-2465. 6. Kantarjian H, O’Brien S, Ravandi F, et al. Proposal for a new risk model in myelodysplastic syndrome that accounts for events not considered in the original International Prognostic Scoring System. Cancer. 2008;113(6):1351-1361. 7. Garcia-Manero G, Shan J, Faderl S, et al. A prognostic score for patients with lower risk myelodysplastic syndrome. Leukemia. 2008;22(3):538-543.