Allogeneic Hematopoietic Cell Transplantation Is an Effective Treatment for Blastic Plasmacytoid Dendritic Cell Neoplasm in First Complete Remission: Systematic Review and Meta-analysis

Introduction: It is common practice to refer patients to transplantation centers for allogeneic hematopoietic cell transplantation (allo-HCT) for blastic plasmacytoid dendritic-cell neoplasm(BPDCN) despite lack of randomized controlled trials. We performed a systematic reviewto assess the totality of evidence pertaining to the efficacy of allo-HCT in BPDCN. Methods: We searched the Cochrane, PubMed, and Embase databases through January 5, 2018, for studies on alloHCT for BPDCN. Two authors independently reviewed all references for inclusion and extracted data related to benefits (overall [OS] and progression-free/disease-free [PFS/DFS] survival) and harms (relapse and nonrelapse mortality) from included studies. When appropriate, data were pooled using random-effects model. Results: Four studies (128 patients) were included in analysis. Pooled OS rate was 50%(95% confidence interval [CI], 41-59) for all patients. Among patients who underwent allografting whose disease was in first complete remission (CR1), pooled OS and PFS/DFS rates were 67% (95% CI, 52-80) and 53% (95% CI, 29-76), respectively. For patients who underwent allografting in > CR1, pooled OS and PFS/DFS rates were 7% (95% CI, 0-32) for both outcomes. Relapse rates were higher when reduced-intensity regimens were used (40% [95% CI, 25-56] vs. 18% [95% CI, 7-31]). Conclusion: This systematic review represents the best available evidence supporting allo-HCT in BPDCN, especially when offered in CR1. Use of myeloablative allo-HCT results in lower pooled relapse rates (18% vs. 40%). A prospective comparative study will be needed to determine the impact of intensity of the conditioning regimen on postallograft relapse. (C) 2018 Elsevier Inc. All rights reserved.