Myeloablative Haploidentical Donor Hematopoietic Transplantation Using Post-Transplantation Cyclophosphamide and Antithymocyte Globulin.

Haploidentical donor (haplo-) hematopoietic stem cell transplantation (HSCT) with post-transplantation cyclophosphamide (PTCy) is now performed on a large scale worldwide. Our patient outcomes did not completely reflect the results published by other groups. We herein present the results of 60 patients with hematologic malignancies treated homogeneously on a modified version of the standard protocol by adding ATG as an additional graft-versus-host disease (GVHD) prophylaxis measure. This was a retrospective analysis of 60 haplo-HSCT recipients using a myeloablative conditioning regimen with antithymocyte globulin and PTCy for GVHD prophylaxis. At 5 years, overall survival was 59.2%, relapse-free survival (RFS) was 48.6%, and chronic GVHD (cGVHD) and relapse-free survival was 40%. The median time to neutrophil and platelet engraftment was 16 days and 28.5 days, respectively. The rates of grade II-IV acute GVHD and extensive cGVHD were 46.7% and 23.3%, respectively. The cumulative incidence of relapse was 30%, nonrelapse mortality was 21.6%, and transplantation-related mortality was 11%. Higher Disease Risk Index and 50% HLA match were associated with lower RFS. Female donor to male recipient and older donor age were associated with an elevated risk of cGVHD. The use of PTCy might not yield the same results in different populations. Many remaining questions need to be addressed in randomized trials, including optimal graft source and donor, date of calcineurin inhibitor initiation, personalized or targeted dose of PTCy, immune reconstitution, and others.

Outcomes of allogeneic hematopoietic cell transplant for acute myeloid leukemia in adolescent patients.

Patients between 14 and 22 years old are underrepresented in both adult and pediatric studies. We analyzed the outcomes of 94 consecutive patients aged between 14 and 22 who underwent myeloablative matched related-donor transplant while in first or second complete remission. We studied the impact of disease type, remission status, ELN risk group, ABO mismatch, time from diagnosis to transplant, patient and donor age, conditioning type, stem cell source, and the year of transplant on transplant outcomes. The cumulative incidences of relapse, NRM, OS, and DFS at 5 years were 42%, 10%, 59%, and 48%, respectively. Absence of ABO mismatch and donor age > 20 were associated with better OS and DFS on univariate and multivariate analysis. The cumulative incidence of aGVHD and cGVHD were 18% and 44%, respectively. Donor age > 20 and peripheral blood stem cell source were significantly associated with higher incidence of cGVHD on univariate and multivariate analysis. Younger patient age was significantly associated with higher incidence of aGVHD. In this age group, the determinants of survival seem to be dependent on donor variables rather on the traditional disease and patient related variables. Relapse still a significant factor for transplant failure while NRM was low.

Efficacy and Feasibility of Sorafenib as a Maintenance Agent After Allogeneic Hematopoietic Stem Cell Transplantation for Fms-like Tyrosine Kinase 3 Mutated Acute Myeloid Leukemia: An Update.

BACKGROUND: Patients diagnosed with acute myeloid leukemia (AML) with Fms-like tyrosine kinase 3 (FLT3) mutations have a very poor prognosis, despite use of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and salvage treatments. PATIENTS AND METHODS: We previously reported the safety and efficacy of sorafenib, an FLT3 inhibitor, as a maintenance agent after allo-HSCT in patients diagnosed with AML with FLT3 mutations. We provide an update on the 27 patients with FLT3-mutated AML in our original report, who received sorafenib as a single maintenance agent. RESULTS: Since our previous report, others have confirmed our reported significant overall survival and progression-free survival in patients who received sorafenib before and/or after allo-HSCT. In this update on the 27 patients with FLT3-mutated AML in our original report, we show persistence of the previously reported impressive long-term disease control. CONCLUSION: Our results, with longer follow-up than in our previous report, together with those of others, further support the use of sorafenib as a maintenance agent after allo-HSCT.

Prognostic role of KIR genes and HLA-C after hematopoietic stem cell transplantation in a patient cohort with acute myeloid leukemia from a consanguineous community.

NK cell activity is tuned by a balance of activating and inhibitory signals transmitted via their respective receptors, including killer immunoglobulin-like receptors (KIRs). The impact of NK cells on graft-versus-leukemia following hematopoietic stem cell transplantation (HSCT) is well established. These effects sometimes lead to GvHD. The link between KIR/HLA interaction and GvHD remains unclear. Herein, we studied the impact of the KIR/HLA interaction on HSCT outcomes in a longitudinal follow-up study of a highly consanguineous HLA-matched related cohort. Peripheral blood DNA was collected from HSCT donor-recipient pairs (n = 87), including 41 AML pairs. KIR and HLA were genotyped and significant results were only measured when matching KIR (donor) with HLA (recipients). GvHD was observed in 47% of patients. KIR2DL1_C2 and 2DS2_C1 (P = 0.02 and 0.04, respectively) matching was associated with an increased incidence of acute GvHD in AML donor-recipient pairs. The rate of chronic GvHD also rose in AML patients who were matched for KIR2DS1_C2 (P = 0.004) and had either KIR2DL2 or KIR2DS2 (P = 0.03). In conclusion, matching of KIR2DL1, 2DS1, and 2DS2 in donors with their HLA-C ligands in recipients is associated with increased GvHD, and holds potential for selection of HSCT donors.