Comparative Review of the Current and Future Strategies to Evaluate Bone Marrow Infiltration at Diffuse Large B-Cell Lymphoma Diagnosis.

Diffuse large B-cell lymphoma (DLBCL) requires a complete staging at diagnosis that may have prognostic and therapeutic implications. The role of bone marrow (BM) biopsy (BMB) is controversial in the era of nuclear imaging techniques. We performed a comparative review of 25 studies focused on BM evaluation at DLBCL diagnosis, including at least two of the following techniques: BMB, flow cytometry, and positron emission tomography (PET-FDG). The report about BM involvement (BMi), diagnostic accuracy, and prognostic significance was collected and compared among techniques. A concordance analysis between BMB, FCM, and PET was also performed, and we deeply evaluated the implications of the different types of BMi: concordant by LBCL or discordant by low-grade B-cell lymphoma for both BMB and FCM, and focal or diffuse uptake pattern for PET. As a main conclusion, BMB, FCM, and PET are complementary tools that provide different and clinically relevant information in the assessment of BMi in newly diagnosed DLBCL.

18F-FDG-PET/CT response after first-line treatment as a prognostic factor for survival in peripheral T-cell lymphoma: a Spanish retrospective study.

BACKGROUND: An accurate assessment of tumor viability after first-line treatment is critical for predicting treatment failure in peripheral T-cell lymphomas (PTCLs). 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) has been adopted as the preferred assessment method in clinical trials, but its impact in clinical practice should be examined. This study aims to determine the prognostic significance of18F-FDG-PET/CT for survival following first-line treatment in PTCL patients. RESEARCH DESIGN AND METHODS: Retrospective observational study including 175 patients diagnosed with PTCL between 2008 and 2013 in 13 Spanish sites. RESULTS: Fifty patients were evaluated with18F-FDG-PET/CT following first-line therapy: 58% were18F-FDG-PET/CT-negative and 42% were18F-FDG-PET/CT-positive. Disease progression occurred in 37.9% of18F-FDG-PET/CT-negative patients and in 80.9% of18F-FDG-PET/CT-positive patients (p = 0.0037). Median progression-free survival and overall survival were 67 and 74 months for18F-FDG-PET/CT-negative patients, and 5 (p < 0.0001) and 10 months (p < 0.0001), respectively, in18F-FDG-PET/CT-positive patients. After multivariate analysis, only B symptoms emerged as a negative predictive factor of complete response (RR 7.08; 95% CI 1.60-31.31; p = 0.001). CONCLUSIONS: 18F-FDG-PET/CT identifies high-risk PTCL patients who will have poor prognosis and survival following first-line treatment. However, more research is needed to confirm the best treatment options for PTCL patients.

COVID-19 Outcomes in Patients with Hematologic Malignancies in the Era of COVID-19 Vaccination and the Omicron Variant.

A greater understanding of clinical trends in COVID-19 outcomes among patients with hematologic malignancies (HM) over the course of the pandemic, particularly the Omicron era, is needed. This ongoing, observational, and registry-based study with prospective data collection evaluated COVID-19 clinical severity and mortality in 1818 adult HM patients diagnosed with COVID-19 between 27 February 2020 and 1 October 2022, at 31 centers in the Madrid region of Spain. Of these, 1281 (70.5%) and 537 (29.5%) were reported in the pre-Omicron and Omicron periods, respectively. Overall, patients aged ≥70 years (odds ratio 2.16, 95% CI 1.64-2.87), with >1 comorbidity (2.44, 1.85-3.21), or with an underlying HM of chronic lymphocytic leukemia (1.64, 1.19-2.27), had greater odds of severe/critical COVID-19; odds were lower during the Omicron BA.1/BA.2 (0.28, 0.2-0.37) or BA.4/BA.5 (0.13, 0.08-0.19) periods and among patients vaccinated with one or two (0.51, 0.34-0.75) or three or four (0.22, 0.16-0.29) doses. The hospitalization rate (75.3% [963/1279], 35.7% [191/535]), rate of intensive care admission (30.0% [289/963], 14.7% [28/191]), and mortality rate overall (31.9% [409/1281], 9.9% [53/536]) and in hospitalized patients (41.3% [398/963], 22.0% [42/191]) decreased from the pre-Omicron to Omicron period. Age ≥70 years was the only factor associated with higher mortality risk in both the pre-Omicron (hazard ratio 2.57, 95% CI 2.03-3.25) and Omicron (3.19, 95% CI 1.59-6.42) periods. Receipt of prior stem cell transplantation, COVID-19 vaccination(s), and treatment with nirmatrelvir/ritonavir or remdesivir were associated with greater survival rates. In conclusion, COVID-19 mortality in HM patients has decreased considerably in the Omicron period; however, mortality in hospitalized HM patients remains high. Specific studies should be undertaken to test new treatments and preventive interventions in HM patients.

Regular Humoral and Cellular Immune Responses in Individuals with Chronic Myeloid Leukemia Who Received a Full Vaccination Schedule against COVID-19.

Individuals with chronic myeloid leukemia (CML) constitute a unique group within individuals with oncohematological disease (OHD). They receive treatment with tyrosine kinase inhibitors (TKIs) that present immunomodulatory properties, and they may eventually be candidates for treatment discontinuation under certain conditions despite the chronic nature of the disease. In addition, these individuals present a lower risk of infection than other immunocompromised patients. For this study, we recruited a cohort of 29 individuals with CML in deep molecular response who were on treatment with TKIs (n = 23) or were on treatment-free remission (TFR) (n = 6), and compared both humoral and cellular immune responses with 20 healthy donors after receiving the complete vaccination schedule against SARS-CoV-2. All participants were followed up for 17 months to record the development of COVID-19 due to breakthrough infections. All CML individuals developed an increased humoral response, with similar seroconversion rates and neutralizing titers to healthy donors, despite the presence of high levels of immature B cells. On the whole, the cellular immune response was also comparable to that of healthy donors, although the antibody dependent cytotoxic activity (ADCC) was significantly reduced. Similar rates of mild breakthrough infections were observed between groups, although the proportion was higher in the CML individuals on TFR, most likely due to the immunomodulatory effect of these drugs. In conclusion, as with the healthy donors, the vaccination did not impede breakthrough infections completely in individuals with CML, although it prevented the development of severe or critical illness in this special population of individuals with OHD.

Remdesivir or Nirmatrelvir/Ritonavir Therapy for Omicron SARS-CoV-2 Infection in Hematological Patients and Cell Therapy Recipients.

BACKGROUND: Scarce data exist that analyze the outcomes of hematological patients with SARS-CoV-2 infection during the Omicron variant period who received treatment with remdesivir or nirmatrelvir/ritonavir. METHODS: This study aims to address this issue by using a retrospective observational registry, created by the Spanish Hematopoietic Stem Cell Transplantation and Cell Therapy Group, spanning from 27 December 2021 to 30 April 2023. RESULTS: This study included 466 patients, 243 (52%) who were treated with remdesivir and 223 (48%) with nirmatrelvir/ritonavir. Nirmatrelvir/ritonavir was primarily used for mild cases, resulting in a lower COVID-19-related mortality rate (1.3%), while remdesivir was preferred for moderate to severe cases (40%), exhibiting a higher mortality rate (9%). A multivariate analysis in the remdesivir cohort showed that male gender (odds ratio (OR) 0.35, p = 0.042) correlated with a lower mortality risk, while corticosteroid use (OR 9.4, p < 0.001) and co-infection (OR 2.8, p = 0.047) were linked to a higher mortality risk. Prolonged virus shedding was common, with 52% of patients shedding the virus for more than 25 days. In patients treated with remdesivir, factors associated with prolonged shedding included B-cell malignancy as well as underlying disease, severe disease, a later onset of and shorter duration of remdesivir treatment and a higher baseline viral load. Nirmatrelvir/ritonavir demonstrated a comparable safety profile to remdesivir, despite a higher risk of drug interactions. CONCLUSIONS: Nirmatrelvir/ritonavir proved to be a safe and effective option for treating mild cases in the outpatient setting, while remdesivir was preferred for severe cases, where corticosteroids and co-infection significantly predicted worse outcomes. Despite antiviral therapy, prolonged shedding remains a matter of concern.

Peripheral T-cell lymphoma with a T follicular-helper phenotype: A different entity? Results of the Spanish Real-T study.

Nodal peripheral T-cell lymphoma (PTCL) with a T follicular helper phenotype (PTCL-TFH) is a new type of PTCL. We aimed to define its clinical characteristics and prognosis compared to PTCL not otherwise specified (PTCL-NOS) and angioimmunoblastic T-cell lymphoma (AITL). This retrospective observational study included 175 patients diagnosed with PTCL between 2008 and 2013 in 13 Spanish sites. Patient diagnosis was centrally reviewed, and patients were reclassified according to the World Health Organization (WHO) 2016 criteria: 21 patients as PTCL-NOS, 55 as AITL and 23 as PTCL-TFH. Median follow-up was 56.07 months (95% CI 38.7-73.4). Progression-free survival (PFS) and overall survival (OS) were significantly higher in patients with PTCL-TFH than in those with PTCL-NOS and AITL (PFS, 24.6 months vs. 4.6 and 7.8 months, respectively, p = 0.002; OS, 52.6 months vs. 10.0 and 19.3 months, respectively, p < 0.001). Histological diagnosis maintained an independent influence on both PFS (hazard ratio [HR] 4.1 vs. PTCL-NOS, p = 0.008; HR 2.6 vs. AITL, p = 0.047) and OS (HR 5.7 vs. PTCL-NOS, p = 0.004; HR 2.6 vs. AITL, p = 0.096), regardless of the International Prognostic Index. These results suggest that PTCL-TFH could have more favourable features and prognosis than the other PTCL subtypes, although larger series are needed to corroborate these findings.

Allogeneic hematopoietic stem cell transplantation for NK/T-cell lymphoma: an international collaborative analysis.

Natural killer/T-cell lymphomas (NKTCL) represent rare and aggressive lymphoid malignancies. Patients (pts) with relapsed/refractory disease after Asparaginase (ASPA)-based chemotherapy have a dismal prognosis. To better define the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT), we conducted a retrospective analysis of data shared with the European Society for Blood and Marrow Transplantation (EBMT) and cooperating Asian centers. We identified 135 pts who received allo-HSCT between 2010 and 2020. Median age was 43.4 years at allo-HSCT, 68.1% were male. Ninety-seven pts (71.9 %) were European, 38 pts (28.1%) Asian. High Prognostic Index for NKTCL (PINK) scores were reported for 44.4%; 76.3% had >1 treatment, 20.7% previous auto-HSCT, and 74.1% ASPA-containing regimens prior to allo-HSCT. Most (79.3%) pts were transplanted in CR/PR. With a median follow-up of 4.8 years, 3-year progression-free(PFS) and overall survival were 48.6% (95%-CI:39.5-57%) and 55.6% (95%-CI:46.5-63.8%). Non-relapse mortality at 1 year was 14.8% (95%-CI:9.3-21.5%) and 1-year relapse incidence 29.6% (95%-CI:21.9-37.6%). In multivariate analyses, shorter time interval (0-12 months) between diagnosis and allo-HSCT [HR = 2.12 (95%-CI:1.03-4.34); P = 0.04] and transplantation not in CR/PR [HR = 2.20 (95%-CI:0.98-4.95); P = 0.056] reduced PFS. Programmed cell death protein 1(PD-1/PD-L1) treatment before HSCT neither increased GVHD nor impacted survival. We demonstrate that allo-HSCT can achieve long-term survival in approximately half of pts allografted for NKTCL.

Persistent Immunity against SARS-CoV-2 in Individuals with Oncohematological Diseases Who Underwent Autologous or Allogeneic Stem Cell Transplantation after Vaccination.

The high morbimortality due to SARS-CoV-2 infection in oncohematological diseases (OHD) and hematopoietic stem cell transplant (HSCT) recipients in the pre-vaccine era has made vaccination a priority in this group. After HSCT, the immune responses against common vaccines such as tetanus, varicella, rubella, and polio may be lost. However, the loss of immunity developed by COVID-19 vaccination after HSCT has not been completely defined. In this study, both humoral and cellular immunity against SARS-CoV-2 were analyzed in 29 individuals with OHD who were vaccinated before receiving allogeneic (n = 11) or autologous (n = 18) HSCT. All participants had low but protective levels of neutralizing IgGs against SARS-CoV-2 after HSCT despite B-cell lymphopenia and immaturity. Although antibody-dependent cellular cytotoxicity was impaired, direct cellular cytotoxicity was similar to healthy donors in participants with autologous-HSCT, in contrast to individuals with allogeneic-HSCT, which severely deteriorated. No significant changes were observed in the immune response before and after HSCT. During follow-up, all reported post-HSCT SARS-CoV-2 infections were mild. This data emphasizes that COVID-19 vaccination is effective, necessary, and safe for individuals with OHD and also supports the persistence of some degree of immune protection after HSCT, at least in the short term, when patients cannot yet be revaccinated.

Patients with secondary acute myeloid leukemia undergoing allogeneic stem-cell transplant have inferior outcomes than de novo acute myeloid leukemia regardless minimal residual disease level by flow cytometry.

Secondary acute myeloid leukemia (s-AML) patients have a poor prognosis and currently the only curative therapy is allogeneic stem-cell transplant (HSCT). However, we do not yet know whether transplantation is sufficient to reverse the poor prognosis compared to de novo AML patients. We analyzed survival after HSCT comparing a cohort of 58 patients with s-AML versus 52 de novo patients who were transplanted between 2012 and 2020. Patients with s-AML had worse event-free survival (EFS) (p = 0.001) and overall survival (OS) (p < 0.001) compared to de novo AML due to an increased risk of relapse (p = 0.06) and non-relapse mortality (p = 0.03). The main difference in survival was observed in patients who achieved complete remission (CR) before HSCT (EFS p = 0.002 OS and <0.001), regardless minimal residual disease (MRD) by |multiparametric flow cytometry cohorts. In patients transplanted with active disease (AD), the prognosis was adverse in both s-AML and de novo AML groups (EFS p = 0.869 and OS p = 0.930). After excluding patients with AD, we stratified the cohort according to conditioning intensity, noticing that s-AML who received MAC had comparable outcomes to de novo AML, but the survival differences remained among reduce intensity conditioning group. In conclusion, transplanted s-AML patients have worse survival among patients in CR before HSCT, regardless of MRD level by flow cytometry compared to de novo AML. MAC patients had similar outcomes irrespective of leukemia ontogeny.

COVID-19 Severity and Survival over Time in Patients with Hematologic Malignancies: A Population-Based Registry Study.

Mortality rates for COVID-19 have declined over time in the general population, but data in patients with hematologic malignancies are contradictory. We identified independent prognostic factors for COVID-19 severity and survival in unvaccinated patients with hematologic malignancies, compared mortality rates over time and versus non-cancer inpatients, and investigated post COVID-19 condition. Data were analyzed from 1166 consecutive, eligible patients with hematologic malignancies from the population-based HEMATO-MADRID registry, Spain, with COVID-19 prior to vaccination roll-out, stratified into early (February-June 2020; n = 769 (66%)) and later (July 2020-February 2021; n = 397 (34%)) cohorts. Propensity-score matched non-cancer patients were identified from the SEMI-COVID registry. A lower proportion of patients were hospitalized in the later waves (54.2%) compared to the earlier (88.6%), OR 0.15, 95%CI 0.11-0.20. The proportion of hospitalized patients admitted to the ICU was higher in the later cohort (103/215, 47.9%) compared with the early cohort (170/681, 25.0%, 2.77; 2.01-3.82). The reduced 30-day mortality between early and later cohorts of non-cancer inpatients (29.6% vs. 12.6%, OR 0.34; 0.22-0.53) was not paralleled in inpatients with hematologic malignancies (32.3% vs. 34.8%, OR 1.12; 0.81-1.5). Among evaluable patients, 27.3% had post COVID-19 condition. These findings will help inform evidence-based preventive and therapeutic strategies for patients with hematologic malignancies and COVID-19 diagnosis.

LAG3 genotype of the donor and clinical outcome after allogeneic transplantation from HLA-identical sibling donors.

Introduction: The association of polymorphisms in molecules involved in the immune response (checkpoint inhibitors) with the clinical outcome after allogeneic transplantation (alloHSCT) has been described. Lymphocyte Activation 3 (LAG3) is a surface protein that plays a regulatory role in immunity as an inhibitory immune checkpoint molecule. Methods: To determine its role in the alloHSCT setting, we analyzed 797 patients transplanted from HLA-identical sibling donors. The LAG3 rs870849 C>T polymorphism was genotyped in donors. Results: We detected a higher incidence of severe acute GVHD in patients transplanted from donors with TT genotype (p: 0.047, HR 1.64; 95% CI 1.01 - 2.67). Overall survival (OS) was worse for patients transplanted from donors with the rs870849 CT/TT genotype (0.020; HR, 1.44; 95% CI 1.06 - 1.96), as well as disease-free survival (DFS) (p: 0.002; HR 1.58, 95%CI: 1.18 - 2.14) and transplant-related mortality (TRM) (p< 0.001; HR: 1.88, 95% CI 1.29 - 2.74). When combining the LAG3 rs870849 and the PDCD1 rs36084323 genotypes of the donor, three genetic groups were well defined, allowing a good stratification of the risk of acute GVHD, TRM, OS and DFS. Discussion: We conclude that the LAG3 genotype of the donor may be considered in donors' selection. As this selection may be limited in the HLA-identical sibling donor scenario, further studies exploring the impact of LAG3 genotype of the donor in unrelated transplantation are warranted.

One-year breakthrough SARS-CoV-2 infection and correlates of protection in fully vaccinated hematological patients.

The long-term clinical efficacy of SARS-CoV-2 vaccines according to antibody response in immunosuppressed patients such as hematological patients has been little explored. A prospective multicenter registry-based cohort study conducted from December 2020 to July 2022 by the Spanish Transplant and Cell Therapy group, was used to analyze the relationship of antibody response over time after full vaccination (at 3-6 weeks, 3, 6 and 12 months) (2 doses) and of booster doses with breakthrough SARS-CoV-2 infection in 1551 patients with hematological disorders. At a median follow-up of 388 days after complete immunization, 266 out of 1551 (17%) developed breakthrough SARS-CoV-2 infection at median of 86 days (range 7-391) after full vaccination. The cumulative incidence was 18% [95% confidence interval (C.I.), 16-20%]. Multivariate analysis identified higher incidence in chronic lymphocytic leukemia patients (29%) and with the use of corticosteroids (24.5%), whereas female sex (15.5%) and more than 1 year after last therapy (14%) were associated with a lower incidence (p < 0.05 for all comparisons). Median antibody titers at different time points were significantly lower in breakthrough cases than in non-cases. A serological titer cut-off of 250 BAU/mL was predictive of breakthrough infection and its severity. SARS-CoV-2 infection-related mortality was encouragingly low (1.9%) in our series. Our study describes the incidence of and risk factors for COVID-19 breakthrough infections during the initial vaccination and booster doses in the 2021 to mid-2022 period. The level of antibody titers at any time after 2-dose vaccination is strongly linked with protection against both breakthrough infection and severe disease, even with the Omicron SARS-CoV-2 variant.

Enhanced thrombin generation detected with ST-Genesia analyzer in patients with newly diagnosed multiple myeloma.

The issue of how to identify newly diagnosed multiple myeloma (NDMM) patients requiring thromboprophylaxis remains unsolved. Several changes in thrombin generation (TG)-derived parameters have been described in multiple myeloma (MM) patients recently. Assessment of prothrombotic risk with a fully automated TG analyzer could reduce interlaboratory variability. Our objective was to determine whether ST-Genesia® could reveal a hypercoagulable state in NDMM compared to healthy controls. We conducted a multicenter observational study of NDMM requiring initial treatment to compare TG parameters obtained with ST-Genesia® analyzer and ST-ThromboScreen® reagent with a control group. Clinical data were obtained from medical records and blood samples were collected before initial anti-myeloma therapy. A thrombophilia panel was performed in all patients. Compared to age- and sex-matched controls (n = 83), NDMM patients (n = 83) had significantly higher peak height, higher velocity index, shorter time-to-peak and lower percentage of endogenous thrombin potential (ETP) inhibition after adding thrombomodulin (TM) (ETP%inh). NDMM on prophylactic low molecular weight heparin (LMWH) showed reduced both peak height and velocity index compared to NDMM who had not yet started VTE prophylaxis, similar to that of controls. Moreover, partial correction of ETP%inh was observed in MM patients on LMWH. The presence of a thrombophilia did not modify the TG phenotype. Untreated NDMM patients showed an enhanced TG, regardless of their thrombophilia status. They generate a higher peak of thrombin, take less time to produce it, and exhibit resistance to TM inhibition. Our findings suggest that standard prophylactic dose of LMWH may reduce TG at levels of healthy controls.

Accuracy and prognostic impact of FDG PET/CT and biopsy in bone marrow assessment of follicular lymphoma at diagnosis: A Nation-Wide cohort study.

BACKGOUND: In the workup of follicular lymphoma (FL), bone marrow biopsy (BMB) assessment is a key component of FLIPI and FLIPI2, the most widely used outcome scores. During the previous decade, several studies explored the role of FDG-PET/CT for detecting nodal and extranodal disease, with only one large study comparing both techniques. METHODS: The aim of our study was to evaluate the diagnostic accuracy and the prognostic impact of both procedures in a retrospective cohort of 299 FL patients with both tests performed at diagnosis. In order to avoid a collinearity bias, FLIPI2 was deconstructed in its founding parameters, and the bone marrow involvement (BMI) parameter separately included as: a positive BMB, a positive PET/CT, the combined "PET/CT and BMB positive" or "PET/CT or BMB positive". These variables were also confronted independently with the POD24 in 233 patients treated with intensive regimens. RESULTS: In the total cohort, bone marrow was involved in 124 and 60 patients by BMB and PET/CT, respectively. In terms of overall survival, age > 60 y.o. and the combined "PET/CT or BMB positive" achieved statistical independence as a prognostic factor. In patients treated with an intensive regimen, only the combined "PET/CT or BMB positive" added prognostic value for a shorter overall survival, when confronted with the POD24. CONCLUSION: Our results show that in FL both BMB and PET/CT should be considered at diagnosis, as their combined assessment provides independent prognostic value in the context of the most widely use clinical scores.

Strong Humoral but Not Cellular Immune Responses against SARS-CoV-2 in Individuals with Oncohematological Disease Who Were Treated with Rituximab before Receiving a Vaccine Booster.

The humoral immune response developed after receiving the full vaccination schedule against COVID-19 is impaired in individuals who received anti-CD20 therapy 6-9 months before vaccination. However, there is little information about the cellular immune responses elicited in these individuals. In this study, we analyzed the humoral and cellular immune responses in 18 individuals with hematological disease who received the last dose of rituximab 13.8 months (IQR 9.4-19) before the booster dose. One month after receiving the booster dose, the seroconversion rate in the rituximab-treated cohort increased from 83.3% to 88.9% and titers of specific IgGs against SARS-CoV-2 increased 1.53-fold (p = 0.0098), while the levels of neutralizing antibodies increased 3.03-fold (p = 0.0381). However, the cytotoxic activity of peripheral blood mononuclear cells (PBMCs) from rituximab-treated individuals remained unchanged, and both antibody-dependent cellular cytotoxicity (ADCC) and direct cellular cytotoxicity (CDD) were reduced 1.7-fold (p = 0.0047) and 2.0-fold (p = 0.0086), respectively, in comparison with healthy donors. Breakthrough infections rate was higher in our cohort of rituximab-treated individuals (33.33%), although most of the infected patients (83.4%) developed a mild form of COVID-19. In conclusion, our findings confirm a benefit in the humoral, but not in the cellular, immune response in rituximab-treated individuals after receiving a booster dose of an mRNA-based vaccine against COVID-19.

Comparison Between Standard and High Dose of G-CSF for Mobilization of Hematopoietic Progenitors Cells in Patients and Healthy Donors.

A standard dose of 10 µg/kg/day granulocyte colony stimulating factors (G-CSF) is currently recommended for hematopoietic progenitor cells (HPCs) mobilization. Our aim was to analyze whether certain patients or healthy donors could benefit from high dose of G-CSF.We performed a retrospective multicenter analysis of HPCs mobilization procedures (2015-2020) in patients and healthy donors. Those who received standard dose of G-CSF (10 µg/Kg/day for 4 days to patients and healthy donors) and those that received higher dose (24 µg/Kg/day for 4 days to patients and 16 µg/Kg/day for 4 days to healthy donors) were compared.496 individuals were included (201 standard dose and 295 higher dose). Between standard or higher dose, we did not find significant differences in median number of mobilized CD34+ cells/mL, neither among healthy donors (77 100 vs 75 500 respectively, P = .895), nor in patients (34 270 vs 33 704 respectively, P = .584). Additionally, among those with the same underlaying pathology the comparison between standard and higher dose did not showed differences. High G-CSF dose was not associated with a less frequent incidence of poor mobilizers (<20 000 CD34+ cells/mL) neither in healthy donors (1 [1.3%] vs 0; P = .218) nor patients (30 [24.4%] vs 32 [18.1%]; P = .165). Multivariate analysis showed that age, gender, and G-CSF dose did not influence median number of mobilized CD34+ cells/mL in healthy donors or patients. However, the underlying pathology among patients significantly influenced the CD34+ cells mobilization. In healthy donors, cellular blood count showed significantly higher leukocytes and platelets count with G-CSF high-dose, while in patients just a higher platelets count was found. To conclude, high dose of G-CSF compared to standard dose did not show significant benefit in terms of mobilization of CD34+ cells in healthy donors or in patients, also without a decrease in the incidence of poor mobilizers.

Humoral/Cellular Immune Discordance in Stem Cell Donors: Impact on Cytomegalovirus-Specific Immune Reconstitution after Related Hematopoietic Transplantation.

Cytomegalovirus (CMV) reactivation is an important cause of complications after hematopoietic stem cell transplantation (HSCT). Discrepancies between serologic and cellular CMV-specific immune response have been reported. This study evaluated the impact of lack of CMV-specific CD8+ T cell response in seropositive donors (ie, discordant donors) on the reconstitution of CMV-specific cell-mediated immunity (CMI) after related HSCT in seropositive recipients. CMV-CMI was assessed in donors and recipients using the QuantiFERON-CMV assay (QF). CMV-CMI was prospectively assessed for 1 year in 81 CMV-seropositive HSCT recipients with a haploidentical or matched related donor. A Cox proportional hazard regression analysis was performed. Of the 67 CMV-seropositive donors, 54 (80.6%) were D+QFpos. The remaining 13 CMV-seropositive donors (19.4%) had a QFneg result and thus were classified as discordant donors (D+QFneg). We found that patients with D+QFneg had a significantly higher risk of impaired CMV-CMI reconstitution compared with patients with D+QFpos (log-rank test, P = .001) or D- donors (log-rank test, P = .023). In addition, the D+QFneg group had a higher incidence of single-episode reactivation compared with D+QFpos or D- donors (69.2% versus 44.4% and 28.6%, respectively) but a lower incidence of CMV recurrence compared with the D- group (7.7% versus 57.1%; P = .003). After adjusting for other relevant variables, immune discordance in donors was independently associated with impaired CMV-CMI reconstitution compared with D+QFpos donors (adjusted hazard ratio [HR], 0.18; 95% confidence interval [CI], .06 to .52; P = .001) and D- donors (adjusted HR, .17; 95% CI, .05 to .59; P = .005). Discordant donors were associated with undetectable CMV-CMI during the 12-month follow-up period using the QF assay. The inability of these patients to become QFpos persisted even after CMV reactivation. This might be related to the low frequency of CMV recurrence in this group. CMV-CMI assessment, in conjunction with CMV serostatus, can be of utility to better classify stem cell donors as well as the risk of impaired CMV-CMI reconstitution after HSCT.

Impact of the Addition of Antithymocyte Globulin to Post-Transplantation Cyclophosphamide in Haploidentical Transplantation with Peripheral Blood Compared to Post-Transplantation Cyclophosphamide Alone in Acute Myelogenous Leukemia: A Retrospective Study on Behalf of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

The use of haploidentical hematopoietic cell transplantation (haplo-HCT) with peripheral blood stem cells (PBSCs) to treat acute myelogenous leukemia (AML) is increasing. We explored whether the addition of antithymocyte globulin (ATG) to post-transplantation cyclophosphamide (PTCy) allows better outcomes compared with PTCy alone in haplo-HCT with PBSCs (haplo-PBSCT). We included 441 adult patients undergoing a first haplo-PBSCT for AML in first or second complete remission; graft-versus-host disease (GVHD) prophylaxis contained either PTCy alone (n = 374) or ATG plus PTCy (n = 67), in addition to cyclosporine A (CsA) and mycophenolate mofetil (MMF) as other immunosuppressive agents. All transplantations were performed between 2011 and 2019. No major imbalances were observed between the 2 groups. For both groups, the median patient age was 56 years, and the median year of haplo-PBSCT was 2017. Most patients received a reduced-intensity conditioning regimen (57% in the PTCy group and 61% in the ATG+PTCy group; P = .54). The median follow-up was 19 months in the PTCy group versus 15 months in the ATG+PTCy group (P = .59), and the rate of neutrophil engraftment in the 2 groups was 97% and 98%, respectively. In univariate analysis, there were no statistical differences in transplantation outcomes between the 2 groups. In multivariate analysis, ATG+PTCy was associated with a lower risk of chronic GVHD compared with PTCy alone (hazard ratio, .46; 95% confidence interval, .23 to .93; P = .03). No between-group differences in the other transplantation outcomes were seen. In haplo-PBSCT, the addition of ATG to PTCy (with CsA and MMF) is feasible and better at preventing chronic GVHD and is associated with survival and transplantation outcomes comparable to those with PTCy alone, without increasing transplantation toxicity, mortality, or relapse incidence.

Early Cellular and Humoral Responses Developed in Oncohematological Patients after Vaccination with One Dose against COVID-19.

Individuals with oncohematological diseases (OHD) may develop an impaired immune response against vaccines due to the characteristics of the disease or to its treatment. Humoral response against SARS-CoV-2 has been described to be suboptimal in these patients, but the quality and efficiency of the cellular immune response has not been yet completely characterized. In this study, we analyzed the early humoral and cellular immune responses in individuals with different OHD after receiving one dose of an authorized vaccine against SARS-CoV-2. Humoral response, determined by antibodies titers and neutralizing capacity, was overall impaired in individuals with OHD, except for the cohort of chronic myeloid leukemia (CML), which showed higher levels of specific IgGs than healthy donors. Conversely, the specific direct cytotoxic cellular immunity response (DCC) against SARS-CoV-2, appeared to be enhanced, especially in individuals with CML and chronic lymphocytic leukemia (CLL). This increased cellular immune response, developed earlier than in healthy donors, showed a modest cytotoxic activity that was compensated by significantly increased numbers, likely due to the disease or its treatment. The analysis of the immune response through subsequent vaccine doses will help establish the real efficacy of COVID-19 vaccines in individuals with OHD.