Comparison of IPSS and IPSS-R Scoring in a Population Based Myelodysplastic Syndromes (MDS) Study

The International Prognostic Scoring System (IPSS) has recently been revised (IPSS-R) to capture more inclusive cytogenetic characterization, more stringent blast description, and more detailed cytopenia assignments. To validate the IPSS-R in a prospective cohort of patients, we compared IPSS and IPSS-R categorization within a group of newly diagnosed MDS patients in a prospective population-based epidemiologic study in Minnesota.

We identified all newly diagnosed MDS cases in Minnesota between the ages of 20 and 85 years from April 1, 2010 to April 2012. Our process includes rapid case identification by the Minnesota Cancer Surveillance System (MCSS), patient contact and enrollment, central medical review including: 1) independent review by two hematopathologists to confirm diagnosis and WHO subclassification; 2) independent cytogeneticist's review for classification as defined by IPSS and IPSS-R; and 3) medical chart review with prospective calculation of IPSS, IPSS-R, and WPSS by a an oncologist.

Classification of the 128 patients by IPSS versus IPSS-R is shown (Table)

Kendall's Tau = 0.77

In this comparative classification, IPSS-R scoring refined the MDS prognostic risk groups. Low IPSS remained low risk in the IPSS-R spanning the Very Low and Low groups, while all high risk IPSS remained in the Very High risk group in the IPSS-R. However, those in the INT-1 and INT-2 IPSS categories were inconsistently reclassified in the IPSS-R. INT-1 IPSS spanned from Very Low to High and INT-2 IPSS spanned from Intermediate to Very High in the IPSS-R. While reclassification of this prospective cohort resembles results in the IPSS-R reports, ongoing follow-up will be needed to determine if the survival and AML progression measures are reproducible.

Until molecular data are available to refine future prognostic scoring systems, the IPSS-R enhances our prognostic risk stratification abilities and is applicable to the general MDS population. As treatment decisions are based on this initial prognostic risk assessment, the more diverse differentiation of risk within the IPSS-R will directly refine prognosis and impact decisions on therapy.

Miller:Celgene: Membership on an entity's Board of Directors or advisory committees; Coronado Bioscience: Membership on an entity's Board of Directors or advisory committees.