Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare fast-growing hematodermic neoplasm that most often occurs in older men. It is notable for its highly aggressive behavior, with cutaneous, lymph node and bone marrow involvement. In the past, BPDCN has been poorly understood, recognized and treated, and consequently has had a poor prognosis. Today, it has been reclassified as a myeloid neoplasm and there is greater understanding of the disease’s clinical features, course and pathology, a new diagnostic test that makes prompt diagnosis possible and a new targeted therapy that, so far, has been shown to at least double survival. The complexity of caring for patients with BPDCN stems from both its rarity and its multiorgan involvement. 'Fast Facts: Blastic Plasmacytoid Dendritic Cell Neoplasm' is designed to bring hematologists, oncologists, dermatologists, pathologists, clinical nurse specialists and trainees in all these fields up to speed on the latest developments, as well as providing the most up-to-date information on first-line chemotherapy, consolidation treatments and stem cell transplantation. It will aid readers of all relevant medical disciplines to implement prompt diagnosis and effective management.

Abstract: Second allogeneic stem-cell transplantation (SCT2) is a therapeutic option for patients with AML relapsing after a first transplant. Prior studies have shown similar results after SCT2 from the same or different donor; however, there are limited data on second non-T-depleted haplo-identical transplant in this setting. We retrospectively analyzed SCT2 outcomes in 556 patients, median age 46 years, relapsing after first transplant given in CR1. Patients were divided into three groups based on SCT2 donor (donor2): same donor (n = 163, sib/sib-112, UD/UD-51), different matched donor (n = 305, sib/different sib-44, sib/UD-93, UD/different UD-168), or haplo-donor (n = 88, sib/haplo-45, UD/haplo-43). Two-year leukemia-free survival (LFS) rate after SCT2 was 23.5%, 23.7%, and 21.8%, respectively (P = 0.30). Multivariate analysis showed no effect of donor2 type on relapse: hazard ratio (HR) 0.89 (P = 0.57) and 1.11 (P = 0.68) for different donor and haplo-donor compared to same donor, respectively. However, donor2 did predict for non-relapse mortality (NRM) after SCT2: HR 1.21 (P = 0.50) and 2.08 (P = 0.03), respectively, and for LFS: HR 1.00 (P = 0.97) and 1.43 (P = 0.07), respectively. In conclusion, SCT2 with the same or different matched donor is associated with similar outcomes in patients with relapsed AML. Non-T-depleted haplo-identical transplant may be associated with higher NRM, similar relapse rate and with no better results in this setting