Livia Giannoni

Integrating post induction WT1 quantification and flow-cytometry results improves minimal residual disease stratification in acute myeloid leukemia

Fifty uniformly treated adult AML patients were analyzed with respect to pre-treatment and post-induction risk factors. Forty-two patients achieving complete hematological remission were assessed for minimal residual disease (MRD) by WT1 gene expression; 34 by flow-cytometry (flow-MRD). Patients who were flow-MRD negative had a better 3-year disease-free (DFS; 79.5% vs. 27.3%; p=.032) compared with patients who were still positive after induction. Interestingly, DFS of flow-MRD positive patients was not related to the amount of flow-detected clone population (≥ or <1%, p=.41) but to WT1 reduction (ΔWT1, 3-year DFS; 46.2% vs. 0% if ΔWT1 was ≥ or < of 1.5 log, p=.001). In AML, combining MRD results provided by WT1 quantification and flow-cytometry improves the reliability of MRD-based prognostic stratification. Similar analyses by further larger studies should be advocated.

Impact of HLA Disparity in Haploidentical Bone Marrow Transplantation Followed by High-Dose Cyclophosphamide

We studied the impact of HLA mismatching on the outcome of 318 consecutive patients who received an unmanipulated haploidentical bone marrow transplant, followed by post-transplant cyclophosphamide (PTCy). The number of HLA-mismatched antigens was tested for its impact on overall survival (OS) and nonrelapse mortality (NRM), whereas HLA mismatches in the graft-versus-host (GVH) direction were tested for prediction of graft-versus-host disease (GVHD and relapse. Finally, we studied whether graft rejection correlated with the number of HLA mismatched antigens in host-versus-graft (HVG) direction. Two hundred thirty-one donor-recipient pairs (72%) had 4/8 mismatches at the -A, -B, -C, -DRB1 HLA loci. HLA mismatches did not predict the 2-year OS (hazard ratio, .83; P = .58) and NRM (subhazard ratio, 1.08; P = .93). The cumulative incidence of acute GVHD (P = .13), 1-year chronic GVHD (P = .84), and relapse rate (P = .26) did not correlate with univectorial GVH mismatches. Similarly, no correlation was observed between the amount of HLA mismatch in the HVG direction and graft rejection. In multivariate analysis advanced disease at transplant was the strongest predictor of survival, NRM, relapse, and graft rejection. In conclusion, the degree of HLA mismatching should not be used as a criterion to select family haploidentical donors when using bone marrow as stem cell source and PTCy for GVHD prophylaxis.

Pre-Engraftment Bloodstream Infections after Allogeneic Hematopoietic Cell Transplantation: Impact of T Cell-Replete Transplantation from a Haploidentical Donor

Bloodstream infections (BSIs) are frequent and important infectious complications after hematopoietic cell transplantation (HCT). The aim of this study was to analyze the incidence, risk factors, and outcome of pre-engraftment BSIs after allogeneic HCT. We retrospectively analyzed data from 553 consecutive patients who underwent HCT between 2010 and 2016. Sixty percent of the patients received T cell-replete unmanipulated haploidentical bone marrow with high-dose post-transplantation cyclophosphamide. The BSI rate was 30%; among isolated 213 pathogens, 54% were Gram-positive, 43% were Gram-negative, and 3% were fungi. Independent risk factors for pre-engraftment BSI were transplantation from a haploidentical donor or from cord blood (P < .001), active disease (P = .002), age (P = .04), and myeloproliferative disorders or aplastic anemia (P < .001). Transplantation from a haploidentical donor was an independent risk factor for both Gram-positive and Gram-negative BSI. The 7-day mortality after any BSI was 5% (9 of 178), and in multivariate analysis, BSI etiology was the sole risk factor, with increased mortality in carbapenem-resistant Gram-negative BSI (P < .001). Nonrelapse mortality at day +60 after HCT was 3.8% (21 of 553); independent predictors were active disease (P = .045), year of HCT (P = .027), nonengraftment (P = .001), and pre-engraftment BSI (P < .001), with significantly higher risk in BSI due to Gram-negative pathogens compared with Gram-positive pathogens, and BSI due to carbapenem-resistant Gram-negative pathogens compared with susceptible pathogens. Pre-engraftment BSI is a frequent complication after HCT from a haploidentical donor or cord blood. Because the negative impact of pre-engraftment BSI on 60-day nonrelapse mortality was caused mainly by carbapenem-resistant Gram-negative pathogens, particular attention should be given to appropriate empiric therapy and management of patients at high risk for Gram-negative BSI.

A blastic plasmacytoid dendritic cell neoplasm-like phenotype identifies a subgroup of npm1-mutated acute myeloid leukemia patients with worse prognosis

To the Editor: As widely reported, isolated NPM1 mutations display a positive prognostic value in acute myeloid leukemia (AML) since they are associated with high complete response rate to chemotherapy and with reduced relapse risk, especially if a molecular complete remission (mCR) is achieved. However, a minority of NPM-mut AML patients do not achieve hematological or mCR or display early relapse, irrespectively of FLT3 status. Despite its recognition as a distinct WHO 2016 entity, NPM-mut AML displays indeed a certain degree of clinical and biological heterogeneity. Morphologic spectrum is wide and can involve all the FAB subtypes, with the exception of M3, with blasts frequently showing monocytic differentiation and cup-like nuclei. Even immunophenotype (IF) is not univocal; NPM-mut cells are usually CD34 negative, CD33 and CD13 positive and a “myeloid” or “monocytic” IF can be usually distinguished. No prognostic relevance has been associated to morphological and immunophenotypic features so far. We retrospectively evaluated 38 consecutive young, de novo NPM-mut AML patients diagnosed in our institution between 2006 and 2014 and treated with a fludarabine, high dose cytarabine and idarubicin (FLAI) based induction. Multicolor cytofluorimetric analysis was routinely performed on bone marrow samples obtained at diagnosis, to define lineage according to WHO 2016, and to identify the leukemia associated phenotypes for minimal residual disease (MRD) monitoring. MRD assessment was performed in all patients with both IF and RQ-PCR for NPM1 expression levels quantification, after induction and each of the consolidation courses. In our experience, a greater than 3.5 logarithmic reduction of NPM1 expression after FLAI induction identified patients with the best probability to achieve mCR and best long term outcome. The retrospective review of leukemic immunophenotypes at diagnosis allowed us to identify three different subgroups of patients; 16/38 displayed a myeloid IF [CD33/CD13/CD38/CD117/MPO (1)]; 7/38 a monocytic IF [CD33/CD64/cyLys/CD11b/CD15 (1) with 3/7 patients CD131]; the third group included 10 patients who displayed both myeloid, and monocytic features [CD33/CD13/CD38/CD117/MPO/ CD64/cLys/CD11b/CD15 (1)]. Five patients could not be assigned to any of those groups. FLT3-ITD mutation was detected in 16/38 (42%) patients. Its incidence was significantly higher in the monocytic group, however this did not translate in a worse outcome (data not shown). No statistically significant differences in relapse free survival (RFS) and overall survival (OS) were detectable among the three IF groups. The expression of CD34 did not negatively affect RFS and OS. Interestingly, searching for recurrent aberrant antigen combinations, we identified six patients with [CD56/CD123/CD4 (1)] coexpression; in other seven patients only two of these three markers were present. Since these markers represent part of the typical blastic plasmacytoid dendritic cell neoplasm (BPDCN) IF, we named this phenotype “BPDCNlike”. BPDCN-like IF was equally distributed among the previously described IF subgroups. Three out of the 6 BPDCN-like patients displayed concomitant FLT3 ITD mutation and all patients had normal karyotype. None of these BPDCN-like patients displayed clinical, morphological and biological features generally associated with BPDCN. Overall, the outcome of BPDCN-like patients was poorer compared to those not expressing this antigen combination. Specifically, five out of six BPDCN-like patients achieved CR after induction (83%) but only one patient achieved mCR. Allogeneic stem cell transplantation (HSCT) was scheduled for refractory patients and for those not achieving mCR, with three patients being transplanted. Three out of five patients not obtaining mCR could not be transplanted due to a sudden unresponsive disease relapse. A complete overview of BPDCN-like patients’ features at diagnosis, response to treatment, and long-term outcome is provided in Table 1. Three year RFS was 28 and 72%, respectively, for patient with or without BPDCN-like phenotype (P< .05), whereas 3-year OS was 0 and 63%, respectively (P<0.05). Furthermore, a trend towards an inferior OS was observed even in the seven patients presenting only two of three BPDCN markers. Although the negative impact of each of these antigens has already been described, to the best of our knowledge this is the first report on the prognostic impact of CD123, CD56, and CD4 coexpression in NPM mut AML. CD123 is strongly expressed by plasmacytoid dendritic cells and by their pathological counterpart in BPDCN and it is widely expressed in hematological malignancies. It is also expressed on physiological CD341 hemopoietic progenitors and on leukemic AML stem cells (LSC). The number of CD1231 LSC has been shown to be predictive of clinical outcome. Interestingly, a negative prognostic impact of CD123 expression in NPM-mut AML has already been

Management of early stage chronic myeloid leukemia: state-of-the-art approach and future perspectives.

Tyrosin kinase inhibitors (TKI), have dramatically changed the natural history of chronic myeloid leukemia (CML) leading to an impressive increase in overall survival rates and allowing many CML patients to achieve a close-to-normal life expectancy. Unfortunately, there is growing evidence that these drugs are not curative, about 30-35% of the patients who receive imatinib become resistant or discontinue the drug because of side effects; moreover, 15% of all patients become resistant to all TKIs, a condition which represents the biggest challenge in CML treatment. Recent progresses in CML stem cell biology have identified new agents and therapeutic strategies that can be used to target the CML stem cell compartment. These studies have opened new perspectives and have highlighted key strategies for treating, and possibly curing, CML in the upcoming years.

Haploidentical Transplants with Post-Transplant Cyclophosphamide for Relapsed or Refractory Hodgkin Lymphoma: The Role of Comorbidity Index and Pretransplant Positron Emission Tomography

Disease relapse remains an unmet medical need for patients with Hodgkin lymphoma (HL) receiving an allogeneic hematopoietic cell transplantation (HCT). With the aim of identifying patients at high risk for post-transplant relapse, we retrospectively reviewed 41 HL patients who had received haploidentical (haplo) nonmyeloablative (NMA) HCT with high dose post-transplant cyclophosphamide (PT-Cy) for graft-versus-host (GVHD) prophylaxis. Primary refractory disease, relapse within 6 months from autologous stem cell transplantation, age, pretransplant chemotherapy, HCT comorbidity index (HCT-CI), sex mismatch, tumor burden and pretransplant fluorodeoxyglucose positron emission tomography (FDG-PET) status, assessed by Deauville score, were analyzed as variables influencing outcomes. All but 1 patient engrafted: median time to neutrophil and platelet recovery was 15 (interquartile range, 13 to 23) days and 19 (interquartile range, 12 to 28) days, respectively. Cumulative incidence of severe (grade III to IV) acute graft-versus-host disease (GVHD) and 3-year moderate-severe chronic GVHD was 2.4% and 11.8%, respectively. The 3-year overall (OS), progression free (PFS), and graft relapse-free survival (GRFS) were 75.6%, 43.9%, and 39%, respectively. On multivariate analysis, 3-year OS was significantly worse in patients with HCT-CI ≥3 (hazard ratio [HR], 5.0; 95% confidence interval [CI], 1.1 to 21.8; P = .03). Three-year relapse rate, 3-year PFS, and 3-year GRFS were significantly worse in patients with HCT-CI ≥3 (HR, 3.5; 95% CI, 1.3 to 9.3; P = .01; HR, 3.3; 95% CI, 1.2 to 9.0; P = .02; and HR, 4.2; 95% CI, 1.7 to 9.9; P = .001, respectively) and in patients with a Deauville score ≥4 on pretransplant FDG-PET (HR, 4.4; 95% CI, 1.6-12.4; P = .005, HR, 3.8; 95% CI, 1.5 to 9.7; P = .005; and 3.2; 95% CI, 1.3 to 7.9; P = .01, respectively). On univariate analysis, 3-year NRM was significantly worse only in patients with a HCT-CI ≥3 (HR, 17.6; 95% CI, 1.4 to 221.0). Among relapsed or refractory HL patients undergoing haplo NMA HCT with PT-Cy, pretransplant FDG-PET with a Deauville score ≥4 and HCT-CI ≥3 identified patients at high risk of relapse. Moreover, an HCT-CI ≥3 was associated with higher NRM and lower OS.

Haploidentical bone marrow transplantation in patients with advanced myelodysplastic syndrome

In 1992, my coworkers and I published a paper in the American Journal of Hematology entitled “On the laboratory problems of diagnosing mild von Willebrand’s disease” and elsewhere another report “On the intraindividual and gender variability of hemostatic components.” Data in both papers were based on fifteen young healthy women, sampled 10-16 times during one month (one menstrual cycle) and on six young men sampled six times during one month. Considerable variations were found in the values of FVIII activity (FVIIIc), VWF:Ag, and VWF ristocetin cofactor (VWF:Rcof) activity, in both genders. In 3 of the 15 female volunteers, the VWF Ag values on some samples were so low that they could be suspected to have a mild form of von Willebrand’s disease (VWD) although they had no history of bleeding; this was associated with high individual variability in VWF:Ag. In one of these females, VWF:Ag varied from a low of 0.25 IU/mL to a high of 1.4 IU/mL (see Fig 1 in reference # 1). In 2001 € Onundarsson et al. investigated VWF activity ((Rcof), VWFAg, and FVIIIc during one menstrual cycle (early, middle, and late phase), in 95 young healthy women but found no comparable variation of these three parameters. Subsequently, we learned that the subjects with the highest VWF variability had run before the blood sampling took place. In our 1992 study, we failed to inform the volunteers that physical and mental stress could influence the results. In 2002 Miller et al. studied 175 women sampled during one cycle and found lowest levels of all three parameters VWF:Ag, VWF:Rcof, and FVIIIc during days 1-4 and highest during days 5-11. In 2007 we and others on behalf of ISTH/SSC summarized key preanalytical requirements such as abstain from physical exercise for at least 24 h; abstain from fatty food and smoking before sampling; take samples in morning hours after sitting in a relaxed position and environment for 20-30 min for equilibration of the hydrostatic pressure. In addition, for the diagnosis of VWD in fertile women, samples should be obtained on cycle days 1-4. Thus, I feel that the limitations of our 1992 study provide an explanation for its discrepant values, and I welcome the opportunity to correct the records.