Abstract Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematological malignancy with a poor prognosis and considered incurable with conventional chemotherapy. Small observational studies reported allogeneic hematopoietic cell transplantation (allo-HCT) offers durable remissions in patients with BPDCN. We report an analysis of patients with BPDCN who received an allo-HCT, using data reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). We identified 164 patients with BPDCN from 78 centers who underwent allo-HCT between 2007 and 2018. The 5-year overall survival (OS), disease-free survival (DFS), relapse, and nonrelapse mortality (NRM) rates were 51.2% (95% confidence interval [CI], 42.5-59.8), 44.4% (95% CI, 36.2-52.8), 32.2% (95% CI, 24.7-40.3), and 23.3% (95% CI, 16.9-30.4), respectively. Disease relapse was the most common cause of death. On multivariate analyses, age of ≥60 years was predictive for inferior OS (hazard ratio [HR], 2.16; 95% CI, 1.35-3.46; P = .001), and higher NRM (HR, 2.19; 95% CI, 1.13-4.22; P = .02). Remission status at time of allo-HCT (CR2/primary induction failure/relapse vs CR1) was predictive of inferior OS (HR, 1.87; 95% CI, 1.14-3.06; P = .01) and DFS (HR, 1.75; 95% CI, 1.11-2.76; P = .02). Use of myeloablative conditioning with total body irradiation (MAC-TBI) was predictive of improved DFS and reduced relapse risk. Allo-HCT is effective in providing durable remissions and long-term survival in BPDCN. Younger age and allo-HCT in CR1 predicted for improved survival, whereas MAC-TBI predicted for less relapse and improved DFS. Novel strategies incorporating allo-HCT are needed to further improve outcomes.
Increased overall and bacterial infections following myeloablative allogeneic HCT for patients with AML in CR1
Abstract Presumably, reduced-intensity/nonmyeloablative conditioning (RIC/NMA) for allogeneic hematopoietic cell transplantation (alloHCT) results in reduced infections compared with myeloablative conditioning (MAC) regimens; however, published evidence is limited. In this Center for International Blood and Marrow Transplant Research study, 1755 patients (aged ≥40 years) with acute myeloid leukemia in first complete remission were evaluated for infections occurring within 100 days after T-cell replete alloHCT. Patients receiving RIC/NMA (n = 777) compared with those receiving MAC (n = 978) were older and underwent transplantation more recently; however, the groups were similar regarding Karnofsky performance score, HCT–comorbidity index, and cytogenetic risk. One or more infections occurred in 1045 (59.5%) patients (MAC, 595 [61%]; RIC/NMA, 450 [58%]; P = .21) by day 100. The median time to initial infection after MAC conditioning occurred earlier (MAC, 15 days [range, <1-99 days]; RIC/NMA, 21 days [range, <1-100 days]; P < .001). Patients receiving MAC were more likely to experience at least 1 bacterial infection by day 100 (MAC, 46% [95% confidence interval (CI), 43-49]; RIC/NMA, 37% [95% CI, 34-41]; P = .0004), whereas at least a single viral infection was more prevalent in the RIC/NMA cohort (MAC, 34% [95% CI, 31-37]; RIC/NMA, 39% [95% CI, 36-42]; P = .046). MAC remained a risk factor for bacterial infections in multivariable analysis (relative risk, 1.44; 95% CI, 1.23-1.67; P < .0001). Moreover, the rate of any infection per patient-days at risk in the first 100 days (infection density) after alloHCT was greater for the MAC cohort (1.21; 95% CI, 1.11-1.32; P < .0001). RIC/NMA was associated with reduced infections, especially bacterial infections, in the first 100 days after alloHCT.