Influence of alternative donor type on early survival after hematopoietic stem cell transplantation for acute myeloid leukemia lacking a sibling donor.

Allogeneic hematopoietic stem cell transplantation is the only potentially curative therapy for acute myeloid leukemia. In the absence of an HLA-matched related or unrelated donor (MRD or MUD), the best alternative donor source remains controversial. Umbilical cord blood and haploidentical donors offer a shorter delay from indication to transplantation. This retrospective multicentre study of a French registry compares overall survival in the 18 months following registration in the absence of a MRD between four types of donors. Between 2012 and 2016, 1302 patients were transplanted using MUD (control, n = 803), mismatched MUD (n = 219), umbilical cord blood (n = 153) and haploidentical (n = 127) donors. Multivariate analyses were conducted for overall survival after registration, after transplant, and transplant-related mortality. After adjustment for variables, the type of donor did not influence any of the three end points. Our results confirmed the significant negative impact of longer time between registration and transplant: HR = 1.04 [1.02-1.06] (p < 0.0001). This indicates a positive correlation between better survival and shorter registration-to-transplantation wait time. In the absence of a sibling donor, the alternative stem cell source does not impact early survival in acute myeloid leukemia patients. The minimization of registration-to-transplantation time should be considered when weighing the alternative donor options.

Characteristics, outcome, and response to therapy of multirefractory chronic immune thrombocytopenia.

Refractory immune thrombocytopenia (ITP) was previously defined as lack of a minimum response to splenectomy and the requirement for long-term treatment to reduce the risk of significant bleeding events. In this multicenter study, we included 37 patients with multirefractory ITP, defined as no response to splenectomy, rituximab, romiplostim, and eltrombopag. As compared with a historical cohort of 183 ITP patients, matched on the calendar year of ITP diagnosis with a 5:1 ratio, patients with multirefractory ITP were more likely to have secondary ITP (odds ratio [OR], 4.84; 95% confidence interval [CI], 1.31-17.86; P = .018) and monoclonal gammopathy of undetermined significance (OR, 5.94; 95% CI, 1.08-32.48; P = .04). The median duration of ITP before being recognized as multirefractory was 78 months (range, 6-450). The patients showed failure of a median of 10.5 prior treatment lines for ITP (range, 6-15). At the end of follow-up (median, 84 months; range, 12-455), only 1/14 patients achieved response with immunosuppressant therapy alone. By contrast, 7/10 patients achieved response with a combination of immunosuppressant therapy and thrombopoietin-receptor agonists that lasted for a median of 15 months (range, 6-32). Throughout the course of ITP, 5/37 patients died, 3 with ITP (bleeding, n = 2; sepsis n = 1); 15 (40%) had at least 1 bacterial infection and 9 (24%) at least 1 episode of thrombosis. In conclusion, multirefractory ITP was associated with high morbidity and mortality. Combining an immunosuppressant therapy with thrombopoietin-receptor agonists may be a good strategy for management for these patients with severe disease.

Impact of Thymoglobulin by Stem Cell Source (Peripheral Blood Stem Cell or Bone Marrow) After Myeloablative Stem Cell Transplantation From HLA 10/10-Matched Unrelated Donors: A Report From the Société Française de Greffe de Moelle et de Thérapie Cellulaire.

BACKGROUND: The impact of antithymocyte globulin (ATG) in the setting of a myeloablative conditioning transplantation remains controversial, especially when using bone marrow (BM) as the stem cell source. METHODS: We therefore conducted a retrospective analysis to investigate the impact of ATG in patients with acute myeloid leukemia or myelodysplastic syndrome receiving myeloablative conditioning followed by a matched 10 of 10 unrelated donor transplant from BM or peripheral blood stem cells (PBSCs). Our study included 356 patients conditioned with cyclophosphamide associated with fractionated total body irradiation or busulfan. RESULTS: Median follow-up was 17.6 months (range, 0-156). The ATG and PBSCs were the only variables that independently decreased the cumulative incidence (CI) of chronic graft-versus-host disease (GvHD) (hazards ratio [HR], 0.4; 95% CI, 0.21-0.73; P < 0.01; and HR, 0.53; 95% CI, 0.30-0.90; P = 0.02, respectively). The ATG had no impact on overall survival, disease-free survival, relapse, and nonrelapse mortality. In the PBSC group (n = 139), ATG was associated with a lower CI of both grades III to IV acute GvHD (HR, 0.17; 95% CI, 0.03-0.91; P = 0.04), chronic GvHD (HR, 0.31; 95% CI, 0.11-0.87; P = 0.03), and GvHD-free/relapse-free survival (HR, 0.48; 95% CI, 0.29-0.80; P < 0.01), whereas these correlations were not significant in the group of patients (n = 217) receiving BM (HR, 0.36; 95% CI, 0.11-1.93; P = 0.06 for grade III-IV acute GvHD; HR, 0.49; 95% CI, 0.22-1.06; P = 0.08 for chronic GvHD; and HR, 0.69; 95% CI, 0.46-1.01; P = 0.06 for GvHD-free/relapse-free survival). CONCLUSIONS: Although our results confirm the recommendation for ATG to be added after PBSC transplantation, no obvious benefit was identified using this approach in the setting of BM transplantation. Only prospective studies may yield definitive answers to this question.

Intragraft Th17 infiltrate promotes lymphoid neogenesis and hastens clinical chronic rejection.

To evaluate the influence of intragraft inflammatory infiltrate on the course of chronic rejection, 11 human renal grafts, detransplanted for terminal failure, were analyzed. Samples were divided into two groups according to their graft survival (> or < or = 8 y). In both groups, the main cell population infiltrating the graft interstitia was T lymphocytes. The extent of the lymphocytic infiltration and the distribution of naive and memory, CD4(+) and CD8(+) T cells, were similar in both groups. Although all types of Th polarization profiles can lead to terminal chronic rejection, a correlation between shorter graft survival and the presence of Th17 cells that produce IL-17 and IL-21 was observed. In contrast, grafts infiltrated by regulatory T cells survived significantly longer. The correlation between the expressions of activation-induced cytidine deaminase (the key enzyme of the germinal center reaction) and IL-21 suggests that Th17 could exert their deleterious effect by promoting lymphoid neogenesis, namely, the organization of inflammatory effectors into ectopic germinal centers in which a local humoral immune response is elicited. Further studies will determine whether Th17 infiltration can be used as a prognosis tool and whether the Th17 subset constitutes a therapeutic target for slowing down chronic rejection.