Response to pretransplant hypomethylating agents influences the outcome of allogeneic hematopoietic stem cell transplantation in adults with myelodysplastic syndromes.

This study describes a retrospective analysis on the transplant outcome of 56 consecutive patients with myelodysplastic syndrome ( MDS) according to their response to hypomethylating agents ( HMA). While 2-yr disease-free survival ( DFS) of patients who transformed to acute myeloid leukemia ( n = 12) was 25%, that of the remaining patients with MDS according to response to HMA was 73.1%, 68.1%, 50.0%, and 20.8% in G- COR (group of continuous response, n = 19), G- No C (group of no change, n = 15), G- LOR (group of loss of response, n = 6), and G- DP (group of disease progression, n = 4), respectively. When dichotomized as G- COR/ G- No C versus G- LOR/ G- DP, significantly different 2-yr DFS (71.0% vs. 33.3%; P = 0.004) and relapse (14.1% vs. 46.7%; P = 0.016) were demonstrated. On multivariate analysis, G- LOR/ G- DP [hazard ratio ( HR), 3.91; P = 0.008] and poor karyotype at transplantation ( HR, 2.69; P = 0.017) were the significant predictors for poor DFS, as G- LOR/ G- DP was for relapse ( HR, 6.28; P = 0.011). DFS was significantly poor in patients with any of the two predictors in all MDS (81.5% vs. 34.9%; P = 0.001) or higher-risk MDS ( Hr MDS) at the time of HMA (80.7% vs. 29.2%; P = 0.005). G- COR showed a trend of better DFS compared with G- No C among Hr MDS (74.6% vs. 36.5%; P = 0.090). These results implicate the significance of response to HMA on hematopoietic stem cell transplantation ( HSCT) outcomes and support the need for future study to verify the suggested strategy of proceeding to transplantation before LOR or DP, especially for Hr MDS. [ABSTRACT FROM AUTHOR]