Long-term survival following autologous and allogeneic stem cell transplantation for blastic plasmacytoid dendritic cell neoplasm.

We sought to clarify the role of high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto-HSCT) and allogeneic hematopoietic stem cell transplantation (allo-HSCT) to treat blastic plasmacytoid dendritic cell neoplasm (BPDCN). We retrospectively identified 25 BPDCN patients (allo-HSCT, n = 14; auto-HSCT, n = 11) from registry data of the Japan Society for Hematopoietic Cell Transplantation and analyzed clinicopathologic data and clinical outcomes after transplantation. The median age at HSCT was 58 years (range, 17-67 years). All 11 patients who underwent auto-HSCT were in the first complete remission (CR1). With a median follow-up of 53.5 months, the overall survival rates at 4 years for patients who underwent auto-HSCT and allo-HSCT were 82% and 53% (P = .11), respectively, and progression-free survival rates were 73% and 48% (P = .14), respectively. Auto-HSCT for BPDCN in CR1 appears to provide promising results and deserves further evaluation in the setting of prospective trials.