Treatment Patterns and Overall Survival in Patients with Intermediate-Risk MDS: A Retrospective Analysis in the Spanish MDS Registry

Background: The Revised International Prognostic Scoring System (IPSS-R) classifies pts with MDS into risk categories, from very low-risk (vLR) to very high-risk (vHR), which guide treatment (tx) options. Pts with intermediate-risk MDS (IR-MDS) are heterogenous and real-world tx practices and outcomes for these pts are unknown. In Spain, the GESMD is an MDS registry containing more than 16,000 pts registered from 142 study sites which represent the country. We evaluated the real-world tx patterns and survival outcomes of pts with MDS from this registry across IPSS-R risk groups (with a focus on IR-MDS) and explored factors driving tx decisions among pts with IR-MDS. Methods: We analyzed the data collected by the GESMD registry from January 2008 to June 2020. Pts included were adults diagnosed with MDS, with informed consent and ≥6-mo follow up if the pt was alive. Pts who did not have available data on their MDS risk score or their use of hypomethylating agent for MDS were excluded. Prior to inclusion in the registry, a curation process was performed to ensure that each pt had the minimum data set and to avoid duplication and errors. Data queries were responded to by physicians at study sites, and the final data included were reviewed by the investigators. Descriptive statistics were used to summarize demographics, clinical, and tx characteristics overall and by risk groups. Overall survival (OS) was analyzed by risk group and tx type using the Kaplan-Meier estimator and 95% confidence intervals (CIs) were calculated. In pts with IR-MDS, a number of baseline variables (including sex, diagnosis year, transfusion status, risk score, age, and blood and blast counts) were explored to assess their relationship with tx selection between either azacitidine (AZA) or best supportive care (BSC) only (eg, transfusions, growth factors). Results: In total, 4,604 pts were included in this analysis. The median age of enrolled pts was 76 y and 39% were female. Other baseline characteristics are seen in Table 1. Seven hundred sixty-one pts (16.5%) were classified as IR-MDS with similar distribution across IPSS-R risk score subgroups 3.5, 4.0, and 4.5. Txs received by pts in the cohort included AZA, chemotherapy, allogeneic stem cell transplant (alloSCT), BSC, and others (eg, immunosuppressors, androgens; Table 2). The majority of pts with IR-MDS were treated with BSC (61%) and AZA (38%). The median time from diagnosis to start of AZA tx ranged from 1 mo in pts with high-ri