A population-based study of survival in patients with secondary myelodysplastic syndromes (MDS): impact of type and treatment of primary cancers

Myelodysplastic syndromes (MDS) following treatment with chemotherapy or irradiation are termed 'secondary' MDS. Clinical observations suggest a worse prognosis for secondary than for primary MDS, but differences in survival have not been studied in a general population sample. We analyzed data from the Surveillance, Epidemiology, and End Results (SEER) program to describe survival in MDS patients according to previous cancer diagnosis. Our study included 3,938 MDS cases diagnosed in 2001-2004 and reported by registries which have participated in SEER since the 1970s. A previous cancer diagnosis (26% of MDS cases) was associated with 13% increased risk of death from any cause among MDS cases (hazard ratio [HR]=1.13, 95% confidence interval [CI]: 1.02-1.25). Radiation treatment for a previous cancer was associated with 52% increased risk of death (95% CI: 1.15-2.02). Shortened survival was most pronounced if the latency between the previous cancer and MDS was less than five years, including lung cancer diagnosed in the year preceding MDS (HR = 3.43, 95% CI: 1.93-6.10) and lymphohematopoietic cancer 1-5 years before MDS (HR = 2.11; 95% CI: 1.33-3.36). Our results confirm a more severe prognosis for secondary MDS than for primary MDS, associated with certain types and treatments of previous cancer.