Myelodysplastic Syndrome: A Study of VA Population.

Background: Epidemiology and outcome of myelodysplastic syndromes (MDS) in the United States is not well recognized. MDS became reportable to the Surveillance, Epidemiology, and End Results program (SEER) in 2001. Only one study is published examining the SEER data between 2001–2003 on MDS incidence, epidemiology and outcome. We report first study of MDS among large population in the Veteran Affair system.

Methods: There are approximately 127 VA Medical Centers diagnosing and/or treating Cancer patients. The data collected by the medical centers cancer registries is aggregated as the VA Central Cancer Registry (VACCR) and is maintained by the Chief Program Office for Oncology at VA in Washington DC. We used the VACCR to analyze VA patients with MDS diagnosed between 1995 and 2005. The data was downloaded from the database using ICD-03 histology codes for MDS. Data was entered and analyzed using bio-statistical software SPSS. Kaplan-Meier curves were used for estimates of overall survival, chi square for comparison of categorical variables and t-test for continuous variables.

Results: Between 1995 and 2005, 1411 MDS cases were registered in the VACCR database. The median age was 75 years. Among those 1379 (97.7%) were males and 1196 (84.4%) were white patients, 171 (12.1%) black, and 44 (3.5%) other race. Majority of cases were reported as MDS, NOS 935 (66.3%), Refractory anemia (RA) 180 (12.8%), Refractory anemia with ring sideroblasts (RARS) 105 (7.4%), Refractory anemia with multilineage dysplasia (RCMD) 22 (1.6%), 5 q syndrome 13 (0.9%), Refractory anemia with excess blasts (RAEB) 105 (7.4%), Refractory anemia with excess blast in transformation 17 (1.2%), and therapy related MDS (t-MDS) 34 (2.4%). No IPSS data were available. The median overall survival (OS) was 1.8 year (95% CI 1.5–2.1). The 3 year and 5 year overall survival was 30% and 22% respectively. The median OS for RA patients was 3.7 year, RARS 4.9 year and for RAEB was 0.8 year. No difference was observed in OS between whites and black (median OS 1.73 versus 2.65, p value 0.28). Their was a non statistically significant trend for improvement of OS in patients diagnosed in 2004–2005 compared to 1995–2003 (time where azacitidine and lenalidomide were approved) median OS of 3.2 versus 1.8 (p value 0.64).

Conclusion: This is the first report of MDS case series in the VA system. Outcome is similar to what is described in literature and SEER data (3 Year OS was 30% in our VA population study compared to 35% in recently published SEER data). No racial disparities are observed in outcome. A trend towards better overall survival is noted in the last 2 years since approval of new treatment options. Coding for WHO subtypes, IPSS and treatment options should be considered in all large MDS registries.