Immunovirology of cytomegalovirus infection in allogeneic stem cell transplant recipients undergoing prophylaxis with letermovir: A narrative review.

On November 7, 2017, the US Food and Drug Administration approved the use of letermovir (LMV) for prophylaxis of cytomegalovirus (CMV) infection in adult CMV-seropositive allogeneic stem cell transplant recipients. After 6 years of use, a large body of real-world experience has been accumulated that validates the Phase III clinical trial results, in which LMV was shown to significantly reduce the risk of clinically significant CMV infection-defined as CMV end-organ disease or CMV DNAemia requiring pre-emptive antiviral therapy (PET)-and increase survival up to Week 24 after treatment inception. Notwithstanding, several issues still need to be settled, thus further investigation is required. First, since viral DNA may accumulate as a result of LMV-driven abortive CMV infection, what is the optimal viral load threshold in the blood that would prompt LMV prophylaxis interruption and PET inception? Should this be adapted to the patient's risk? Second, what is the impact of LMV prophylaxis on the reconstitution of functional CMV-specific T-cell responses? Would it be a wise approach to individually tailor the duration of LMV treatment according to the number of peripheral blood CMV-specific T cells at the end of regular prophylaxis? Third, how frequently do LMV-resistant strains arise while patients are on LMV prophylaxis and how could this be minimized? Here, we discuss the literature addressing these topics.

Monitoring of plasma Torque teno virus, total Anelloviridae and Human Pegivirus 1 viral load for the prediction of infectious events and acute graft versus host disease in the allogeneic hematopoietic stem cell transplantation setting.

Anelloviridae and Human Pegivirus 1 (HPgV-1) blood burden have been postulated to behave as surrogate markers for immunosuppression in transplant recipients. Here, we assessed the potential utility plasma Torque teno virus (TTV), total Anelloviridae (TAV), and HPgV-1 load monitoring for the identification of allogeneic hematopoietic stem cell transplantation recipients (allo-HSCT) at increased risk of infectious events or acute graft versus host disease (aGvHD). In this single-center, observational study, plasma TTV DNA, TAV DNA, and HPgV-1 RNA loads were monitored in 75 nonconsecutive allo-HSCT recipients (median age, 54 years). Monitoring was conducted before at baseline or by days +30, +60, +90, +120, and +180 after transplantation. Pneumonia due to different viruses or Pneumocystis jirovecii, BK polyomavirus-associated haemorrhagic cystitis (BKPyV-HC), and Cytomegalovirus DNAemia were the infectious events considered in the current study. Kinetics of plasma TTV, TAV DNA, and HPgV-1 RNA load was comparable, with though and peak levels measured by days +30 and day +90 (+120 for HPgV-1). Forty patients (53%) developed one or more infectious events during the first 180 days after allo-HSCT, whereas 29 patients (39%) had aGvHD (grade II-IV in 18). Neither, TTV, TAV, nor HPgV-1 loads were predictive of overall infection or CMV DNAemia. A TTV DNA load cut-off ≥4.40 log10 (pretransplant) and ≥4.58 log10 (baseline) copies/mL predicted the occurrence of BKPyV-HC (sensitivity ≥89%, negative predictive value, ≥96%). TTV DNA loads ≥3.38 log10 by day +30 anticipated the occurrence of aGvHD (sensitivity, 90%; negative predictive value, 97%). Pretransplant HPgV-1 loads were significantly lower (p = 0.03) in patients who had aGvHD than in those who did not. Monitoring of TTV DNA or HPgV-1 RNA plasma levels either before or early after transplantation may be ancillary to identify allo-HSCT recipients at increased risk of BKPyV-HC or aGvHD.

Respiratory virus infections after allogeneic stem cell transplantation: Current understanding, knowledge gaps, and recent advances.

Before the COVID-19 pandemic, common community-acquired seasonal respiratory viruses (CARVs) were a significant threat to the health and well-being of allogeneic hematopoietic cell transplant (allo-HCT) recipients, often resulting in severe illness and even death. The pandemic has further highlighted the significant risk that immunosuppressed patients, including allo-HCT recipients, face when infected with SARS-CoV-2. As preventive transmission measures are relaxed and CARVs circulate again among the community, including in allo-HSCT recipients, it is crucial to understand the current state of knowledge, gaps, and recent advances regarding CARV infection in allo-HCT recipients. Urgent research is needed to identify seasonal respiratory viruses as potential drivers for future pandemics.

Cytomegalovirus DNAemia and risk of mortality in allogeneic hematopoietic stem cell transplantation: Analysis from the Spanish Hematopoietic Transplantation and Cell Therapy Group.

The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.

An investigation of the potential association between gastrointestinal viral and bacterial infection and development of intestinal acute graft versus host disease following allogeneic hematopoietic stem cell transplantation.

It is uncertain whether gastrointestinal (GI) infection caused by viral and bacterial pathogens may predispose to gastrointestinal acute Graft-versus-host disease (aGvHD-GI) in allogeneic hematopoietic stem cell transplant recipients (allo-HSCT). We investigated the potential association between detection of enteropathogenic viruses or bacteria in stools and subsequent occurrence of aGvHD-GI in a cohort of 121 allo-HSCT patients. Eighty-six out of 121 patients (71%) had acute diarrhea and underwent screening for primary GI pathogens by molecular diagnostic methods. One or more GI pathogens were detected in 27 out of the 86 patients with diarrhea (31.3%). Specifically, Clostridioides difficile was found in 16 patients (18.6%), enteropathogenic viruses in 11 patients (12.7%) (Astrovirus, n = 4; Norovirus, n = 2; Sapovirus, n = 2; Adenovirus, n = 2; and Rotavirus, n = 1), and Campylobacter spp. in two patients (2.3%). Thirty patients were diagnosed with all grade aGvHD-GI by histopathology. Detection of primary GI pathogens was achieved in 12 out of 30 patients (Clostridium difficile, n = 5; enteric viruses, n = 8; Campylobacter spp., n = 1) who either subsequently developed (n = 9) or previously had (n = 3) grade I-IV IaGvHD (n = 9). Neither the detection of these microorganisms (all combined), enteric viruses, nor C. difficile was significantly associated with subsequent aGvHD-GI development in Cox models (hazard ratio [HR] = 1.11, p = .80; HR = 1.64, p = .62; HR = 0.75, p = .64, respectively). Analogous results were obtained when grade II-IV aGvHD-GI was selected as the clinical outcome. In summary, data in the current study did not support an association between GI infection and subsequent occurrence of aGvHD-GI in an unselected cohort of allo-HSCT recipients.

Healthcare resource utilization in adult patients with relapsed/refractory FLT3 mutated acute myeloid leukemia: A retrospective chart review from Spain.

BACKGROUND: Information regarding impact on healthcare systems of relapsed or refractory (R/R) FLT3 mutated (FLT3mut) acute myeloid leukemia (AML) is scarce. OBJECTIVE: To assess the time and reimbursement associated with hospitalizations of patients with R/R FLT3mut AML in a tertiary Spanish hospital. METHODS: Retrospective review of medical charts identified patients aged ≥ 18 years with R/R FLT3mut AML between 1998 and 2018. Data were collected from the date of first diagnosis of R/R FLT3mut AML (index) until death or loss to follow-up. The primary end point was duration and frequency of hospitalization, use of outpatient resources and transfusion burden. Reimbursement associated with hospitalizations (including associated chemotherapy) was also assessed. RESULTS: Thirty-eight patients were eligible for inclusion. Their median age was 52 years, and 30 (79%) received intensive salvage chemotherapy; FLAG-IDA-based regimens were the most frequent (24 patients, 63%). Overall, there were 150 hospitalizations (mean 3.9/patient; mean duration 21 days). Patients spent a mean of 24% of the study period in hospital. Total mean reimbursement was €108 293 per patient; the majority (€89 834) attributable to inpatient stays (€22 576 /hospitalization). During chemotherapy period (prior to first alloHSCT), there were 73 hospitalizations (mean duration 22 days); mean reimbursement was €19 776 per hospitalization and €49 819 per patient. AlloHSCT (n = 16) involved 77 hospitalizations (mean duration 21 days), mean reimbursement €25 231/hospitalization and €131 515 per patient. CONCLUSION: Data from this study suggest that there is a substantial healthcare resource utilization and cost burden on R/R FLT3mut AML patients in Spain receiving active treatments.

Partial T Cell-Depleted Peripheral Blood Stem Cell Transplantation from HLA-Identical Sibling Donors for Patients with Severe Aplastic Anemia.

We analyzed the outcomes of 26 consecutive patients with acquired severe aplastic anemia (SAA) undergoing peripheral blood stem cell transplantation (PBSCT) with partial ex vivo T cell depletion with a targeted T cell dose from HLA-identical sibling donors. The median patient age was 37 years (range, 3 to 63 years). Four patients with uncontrolled pneumonia at the time of transplantation died, on days +1, +2, +21, and +26. All evaluable patients engrafted, with a median time to neutrophil recovery of 11 days (range, 10 to 14 days) and a median time to platelet recovery of 19 days (range, 8 to 53 days). Two patients had transient grade I acute graft-versus-host disease (GVHD) with skin involvement, but no patients developed grade II-IV acute GVHD. Two patients had mild skin chronic GVHD, and 1 patient had moderate chronic GVHD with ocular involvement. No relapse was observed after a median follow-up of 114 months (range, 4 to 233 months). The overall cumulative incidence of TRM at 10 years was 19%, whereas it was 5% for those with a Karnofsky Performance Status (KPS) score >60 at the time of transplantation. Disease-free survival, overall survival, and GVHD and relapse-free survival at 10 years were 81%, 81%, and 80%, respectively, for all patients and 95%, 95%, and 90%, respectively, for patients with a KPS score >60 at transplantation. Our data indicate that PBSCT with partial ex vivo T cell-depleted targeted cell dose grafts from an HLA-identical sibling donor is a feasible, safe, and effective approach to reduce GVHD and cure patients with SAA.

Invasive fungal disease in patients undergoing umbilical cord blood transplantation after myeloablative conditioning regimen.

OBJECTIVE: Characteristics and risk factors (RFs) of invasive fungal disease (IFD) have been little studied in the setting of umbilical cord blood transplantation (UCBT). METHOD: We retrospectively included 205 single-unit myeloablative UCBT recipients with a median follow-up of 64 months. RESULTS: Fifty-six episodes of IFD were observed in 48 patients (23%) at a median time of 123 days after stem cell infusion. Invasive mold disease (IMD) occurred in 42 cases, 38 of them (90%) caused by invasive aspergillosis whereas invasive yeast disease (IYD) occurred in 14 cases, most of them due to candidemia (n = 12, 86%). The 5-year cumulative incidence of IFD, IMDs, and IYDs was 24% 19%, and 7%, respectively. In multivariate analysis, three RFs for IMDs were identified: age >30 years (HR 3.5, P = 0.017), acute grade II-IV graft-versus-host disease (HR 2.3, P = 0.011), and ≥1 previous transplant (HR 3.1, P = 0.012). The probability of IMDs was 2.5%, 14%, and 33% for recipients with none, 1, or 2-3 RFs, respectively (P < 0.001). Among IFD, IMDs had a negative effect on non-relapse mortality in multivariate analysis (HR 1.6, P = 0.039). IMDs showed a negative impact on overall survival (HR 1.59, P = 0.018). CONCLUSION: Invasive mold disease were very common and serious complication after UCBT.

Pharmacokinetic/Pharmacodynamic Analysis of Voriconazole Against Candida spp. and Aspergillus spp. in Allogeneic Stem Cell Transplant Recipients.

BACKGROUND: To evaluate the adequacy of different dosing regimens of voriconazole for the prophylaxis of invasive candidiasis and aspergillosis in adult allogeneic stem cell transplant recipients by means of population pharmacokinetic (PK) modelling and simulation. METHODS: Allogeneic stem cell transplant recipients receiving voriconazole were included in this observational study. A population PK model was developed. Three oral voriconazole-dosing regimens were simulated: 200, 300, and 400 mg twice daily. The pharmacodynamic target was defined as fAUC0-24/0.7. A probability of target attainment ≥90% was considered optimal. The cumulative fraction of response was defined as the fraction of patients achieving the pharmacodynamic target when a population of simulated patients is matched with a simulated population of different Candida spp. and Aspergillus spp. The percentage of patients with trough plasma concentrations at steady state (Ctrough) within the reference range (1-5.5 mg/L) was also calculated. RESULTS: A 2-compartment PK model was developed using data from 40 patients, which contributed 237 voriconazole plasma samples, including trough and maximum concentrations. Voriconazole 200, 300, and 400 mg twice daily achieved probability of target attainment ≥90% for minimal inhibitory concentration values ≤0.25, ≤0.38, and ≤0.50 mg/L, respectively. The cumulative fraction of response for A. niger, A. versicolor, and A. flavus increased >10% when increasing voriconazole dose from 200 to 400 mg twice daily (from 72.5% to 89.5% for A. niger; from 77.7% to 88.7% for A. versicolor; and from 82.4% to 94.9% for A flavus). The percentage of patients with Ctrough within the reference range increased 15% when voriconazole dose was increased from 200 to 300 mg twice daily. CONCLUSIONS: The PK simulations in this study suggest that transplant recipients on voriconazole prophylaxis against invasive candidiasis or aspergillosis are likely to achieve the target concentrations associated with the desired treatment outcomes if the maintenance dose is 200 mg twice daily. However, Aspergillus spp. with high minimal inhibitory concentrations could require higher maintenance doses.

Validation of a multivariable prediction model for post-engraftment invasive fungal disease in 465 adult allogeneic hematopoietic stem cell transplant recipients.

BACKGROUND: Recently, we reported a simple prognostic score for post-engraftment invasive fungal disease (IFD) obtained in 404 adult allogeneic hematopoietic stem cell transplant (alloSCT) (training cohort). OBJECTIVES: We aim to validate this score in an external cohort assessing the 1-year cumulative incidence (CI) of post-engraftment IFD. Additionally, we analyse the type of IFD and incidence of IFD according to type of prophylaxis. PATIENTS/METHODS: We included 465 consecutive adult recipients surviving >40 days who engrafted and were discharged without prior IFD (median age 45 years, range, 14-69). RESULTS: Patients classified as low-risk, 139; intermediate-risk, 162; and high-risk, 164 (35% vs 27% in the training cohort, P = 0.03). The CI of probable/proven IFD in the validation cohort was 8% vs 11% in the training cohort (P = 0.006). The only voriconazole prophylaxis used in the training cohort was 100 mg/12 h, 65% vs 27% in the validation cohort, but 38% received 200 mg/12 h. Thus, the validation cohort showed a lower CI of IFD (P = 0.009). The post-engraftment IFD score was validated, showing a CI of IFD for low-, intermediate- and high-risk of 3%, 6% and 14%, respectively (P < 0.001). CONCLUSION: To our knowledge, this is the first prognostic index to predict the occurrence of post-engraftment IFD after alloSCT that has been validated in an external cohort.

T lymphocytes as therapeutic arsenal for patients with hematological malignancies.

PURPOSE OF REVIEW: We present an overview of the clinically available immunotherapeutic platforms centered on T cell lymphocytes for the treatment of hematological malignancies with a special focus on the advances achieved since 2017. RECENT FINDINGS: The most promising strategies of T cell therapies are based on the infusion of unmanipulated donor lymphocytes, antigen-specific T cells, ex-vivo genetically modified T cells or in-vivo manipulation of T cells using antibodies (bispecific and checkpoint inhibitors). To select the most appropriate option for a specific patient, is important to understand not only each platform-specific biological mechanisms, clinical activity and toxicities but also their intrinsic differences. In this extremely fast-growing field, to keep track of recent advances is a hard and challenging task for a hematologist. Therefore, we aimed to provide a global integrative review of T-cell-based immunotherapies, essential to ascertain their optimal place and timing in our daily clinical practice. SUMMARY: We highlight recent advances and discuss future directions of T-cell-based immunotherapies entering the common clinical practice in hematology.

Monitoring of oral cytomegalovirus DNA shedding for the prediction of viral DNAemia in allogeneic hematopoietic stem cell transplant recipients.

Preemptive antiviral therapy based on detecting cytomegalovirus (CMV) DNAemia above a preestablished threshold is the mainstay strategy for the prevention of CMV disease in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients; nevertheless, CMV DNAemia, even at low levels, may increase mortality. We investigated whether surveillance of saliva for the presence of CMV DNA may anticipate the occurrence of CMV DNAemia. This was a prospective observational study with 53 consecutively enrolled allo-HSCT recipients. Saliva and plasma specimens were collected on a weekly basis from Day 0 to Day 100 after transplantation. CMV DNA was quantified in both specimen types using the Abbott Real-Time PCR assay (Abbott Molecular, Des Plaines, IL). CMV DNA was quantifiable in 44 (83%) patients: either in saliva (n = 1) or plasma (n = 12) only, or in both specimen types (n = 31). CMV oral shedding preceded the occurrence of CMV DNAemia in eight patients (18.2%), while the opposite pattern was observed in 21 patients (47.7%). The CMV DNA loads quantified in saliva and plasma correlated modestly (P = 0.33; P = 0.013) and did not differ in magnitude (P = 0.527). No transplantation factors, other than recipient CMV seropositivity, were associated with oral CMV DNA shedding; serum CMV IgG levels were comparable, regardless of the timing of the detection of CMV DNA at both sites. In summary, screening of saliva specimens for the presence of CMV DNA appear to be of limited value for anticipating the occurrence of CMV DNAemia in allo-HSCT recipients.

Lack of evidence for a reciprocal interaction between bacterial and cytomegalovirus infection in the allogeneic stem cell transplantation setting.

Pathogenic interactions between bacteria and cytomegalovirus (CMV) may potentially occur early after allogeneic stem cell transplantation (allo-SCT). This possibility nevertheless has not been investigated in depth. This was a retrospective study that included 170 consecutive patients who underwent 173 allo-SCTs. Both bacterial infection (most of which were bacteremic) and CMV DNAemia were detected in 78 allo-SCTs (62.9%). In total, 51 and 32 episodes of bacterial infection preceded or occurred after CMV DNAemia detection, respectively. Both events were diagnosed concurrently in four allo-SCTs. The cumulative incidence of bacterial infection (of any type) over the study period was comparable in patients with or without a preceding episode of CMV DNAemia (P = 0.321). Cox proportional hazards regression analysis failed to identify CMV DNAemia as a significant risk factor for bacterial infection. Likewise, the cumulative incidence of CMV DNAemia within the study period was not significantly different in patients with or without a preceding episode of bacterial infection (P = 0.189). Furthermore, the occurrence of bacterial infection within episodes of active CMV infection had no apparent impact on the kinetics of CMV DNAemia. Our data, thus, do not support the existence of a bidirectional synergistic effect between bacterial infection and active CMV infection in the allo-SCT setting.

Prognostic value of genetic alterations and 18F-FDG PET/CT imaging features in diffuse large B cell lymphoma.

The current standard front-line therapy for patients with diffuse large-B cell lymphoma (DLBCL)-rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP)-is found to be ineffective in up to one-third of them. Thus, their early identification is an important step towards testing alternative treatment options. In this retrospective study, we assessed the ability of 18F-FDG PET/CT imaging features (radiomic + PET conventional parameters) plus clinical data, alone or in combination with genomic parameters to predict complete response to first-line treatment. Imaging features were extracted from images prior treatment. Lesions were segmented as a whole to reflect tumor burden. Multivariate logistic regression predictive models for response to first-line treatment trained with clinical and imaging features, or with clinical, imaging, and genomic features were developed. For imaging feature selection, a manual selection approach or a linear discriminant analysis (LDA) for dimensionality reduction were applied. Confusion matrices and performance metrics were obtained to assess model performance. Thirty-three patients (median [range] age, 58 [49-69] years) were included, of whom 23 (69.69%) achieved long-term complete response. Overall, the inclusion of genomic features improved prediction ability. The best performance metrics were obtained with the combined model including genomic data and built applying the LDA method (AUC of 0.904, and 90% of balanced accuracy). The amplification of BCL6 was found to significantly contribute to explain response to first-line treatment in both manual and LDA models. Among imaging features, radiomic features reflecting lesion distribution heterogeneity (GLSZM_GrayLevelVariance, Sphericity and GLCM_Correlation) were predictors of response in manual models. Interestingly, when the dimensionality reduction was applied, the whole set of imaging features-mostly composed of radiomic features-significantly contributed to explain response to front-line therapy. A nomogram predictive for response to first-line treatment was constructed. In summary, a combination of imaging features, clinical variables and genomic data was able to successfully predict complete response to first-line treatment in DLBCL patients, with the amplification of BCL6 as the genetic marker retaining the highest predictive value. Additionally, a panel of imaging features may provide important information when predicting treatment response, with lesion dissemination-related radiomic features deserving especial attention.

Evaluation of prognostic factors among patients with chronic graft-versus-host disease.

BACKGROUND: Chronic graft-versus-host disease (cGVHD) is a major complication after allogeneic stem cell transplantation with an adverse effect on both mortality and morbidity. In 2005, the National Institute of Health proposed new criteria for diagnosis and classification of chronic graft-versus-host disease for clinical trials. New sub-categories were recognized such as late onset acute graft-versus-host disease and overlap syndrome. DESIGN AND METHODS: We evaluated the prognostic impact of the new sub-categories as well as the clinical scoring system proposed by the National Institute of Health in a retrospective, multicenter study of 820 patients undergoing allogeneic stem cell transplantation between 2000 and 2006 at 3 different institutions. Patients were retrospectively categorized according to the National Institute of Health criteria from patients' medical histories. RESULTS: As far as the new sub-categories are concerned, in univariate analysis diagnosis of overlap syndrome adversely affected the outcome. Also, the number of organs involved for a cut-off value of 4 significantly influenced both cGVHD related mortality and survival. In multivariate analysis, in addition to NIH score, platelet count and performance score at the time of cGVHD diagnosis, plus gut involvement, significantly influenced outcome. These 3 variables allowed us to develop a simple score system which identifies 4 subgroups of patients with 84%, 64%, 43% and 0% overall survival at five years after cGVHD diagnosis (score 0: HR=15.96 (95% CI: 6.85-37.17), P<0.001; score 1: HR=5.47 (95% CI: 2.6-11.5), P<0.001; score 2: HR=2.8 (95% CI: 1.32-5.93), P=0.007). CONCLUSIONS: In summary, we have identified a powerful and simple tool to discriminate different subgroups of patients in terms of chronic graft-versus-host disease related mortality and survival.

Degree of mucositis and duration of neutropenia are the major risk factors for early post-transplant febrile neutropenia and severe bacterial infections after reduced-intensity conditioning.

BACKGROUND AND OBJECTIVES: Whether the intensity of the conditioning regimen affects febrile neutropenia (FN) and severe bacterial infections (SBIs) is not well established. We analyzed the risk factors (RFs) for the development of FN and SBI in the first 100d post-transplant in 195 consecutive adult recipients of a reduced-intensity conditioning allogeneic hematopoietic stem cell transplantation (RIC-allo). MATERIALS AND METHODS: The RIC regimens consisted of fludarabine plus melphalan (62%) or busulphan (38%) (FluMel or FluBu). SBIs include pneumonia, urinary tract infections, and bacteremia. RESULTS: FN occurred in 141 patients (72%), always in the first 30d post-allo-RIC. However, a SBI occurred in only 27 patients (14%) during this early post-transplant period (

Allogeneic Hematopoietic Stem Cell Transplantation in Transformed Follicular Lymphoma (tFL): Results of a Retrospective Multicenter Study from GELTAMO/GETH-TC Spanish Groups.

BACKGROUND: Transformation of follicular lymphoma into an aggressive lymphoma (tFL) worsens the prognosis and the standard treatment is not completely defined. Allogeneic hematopoietic stem cell transplantation (alloSCT) could be a potentially curative option for these patients, but it has not been widely explored. METHODS: We designed a retrospective multicenter study to analyze the efficacy and toxicity of alloSCT in tFL patients and potential prognostic factors of survival. RESULTS: A total of 43 patients diagnosed with tFL who underwent alloSCT in 14 Spanish centers between January 2000 and January 2019 were included. Median age was 44 (31-67) years. After a median follow-up of 58 months, estimated 5-year overall survival (OS) and progression-free survival (PFS) were both 35%. Estimated 100-day and 1-year non-relapse mortality (NRM) were 20% and 34%, respectively. The type of conditioning regimen (3-year OS of 52% vs. 20%, respectively, for reduced-intensity vs. myeloablative conditioning) and development of chronic graft versus host disease (cGVHD) (3-year OS of 75% vs. 40%) were the only factors significantly associated with OS. The only variable with an independent association with OS was cGVHD (HR, 3.4; 95% CI, 1.2-9.6). CONCLUSIONS: Our results indicate that alloSCT continues to be a potentially curative option for patients with tFL.

Evolving patterns of care and outcomes in relapsed/refractory FLT3 mutated acute myeloid leukemia adult patients.

We have analyzed treatment patterns and outcomes of relapsed/refractory(R/R) FLT3mut AML adult patients registered in our institutional data base between 1998 and 2018. Overall, 147 patients were evaluable: 34 from 1998 to 2009, 113 from 2010 to 2018. Salvage treatments were intensive chemotherapy (n = 25, 74%), and supportive care (n = 9, 26%) in the 1998-2009 period, and intensive chemotherapy (n = 63, 56%), hypomethylating agent (n = 7, 6%), low-dose cytarabine-based (n = 8, 7%), clinical trial (n = 16, 14%) and supportive care (n = 19, 17%) in the 2010-2018 period. Complete remission (CR) or with incomplete recovery (CRi) rate was 44%, 49% among patients treated intensively (vs 30% with non-intensive p = 0.005). Median overall survival since first R/R was 5.8 months, and 16.3 months in subjects receiving an allo-HSCT in CR/CRi after first salvage (vs 3.8 in the remaining patients p < 0.0001). Clinical outcomes of R/R FLT3mut AML remain unsatisfactory. Inclusion in clinical trials and expanding options could lead to improved outcomes.

Allogeneic Stem Cell Transplantation in Mature T Cell and Natural Killer/T Neoplasias: A Registry Study from Spanish GETH/GELTAMO Centers.

Despite advances in understanding the biology of mature T and natural killer (NK)/T cell neoplasia, current therapies, even the most innovative ones, are still far from ensuring its cure. The only treatment to date that has been shown to control aggressive T cell neoplasms in the long term is allogeneic stem cell transplantation (alloSCT). We aim to report the results of alloSCT for advanced mature T and NK/T neoplasias performed in centers from our national GELTAMO/GETH (Grupo Español de Linfoma y Trasplante de Médula Ósea/Grupo Español de Trasplante Hematopoyético y Terapia Celular) over the past 25 years. As a secondary objective, we analyzed the results of alloSCT from haploidentical donors. We performed a retrospective analysis of all patients who received an alloSCT in Spanish centers (n = 201) from September 1995 to August 2018. The 2-year overall survival (OS) and disease-free survival (DFS) were 65.5% and 58.2%, respectively. The univariate for OS and DFS showed statistically different hazard ratios for conditioning intensity, response pre-alloSCT, comorbidity index, donor/receptor cytomegalovirus status and Eastern Cooperative Oncology Group (ECOG) pre-alloSCT, but only a better ECOG pre-alloSCT remained significant in the multivariate analysis. There was an increased incidence of relapse in those patients who did not develop chronic graft-versus-host disease (GVHD) and an increased risk of death in those developing moderate to severe acute GVHD. The 1-year nonrelapse mortality was 21.9% and was mainly due to GVHD (30%) and bacterial infections (17%). When comparing unrelated donors with haploidentical donors, we found similar results in terms of OS and DFS. There was, however, a reduction of acute GVHD in the haploidentical group (P = .04) and trend to a reduction of chronic GVHD. In conclusion, alloSCT is the only curative option for most aggressive T cell neoplasias. Haploidentical donors offer similar results to related donors in terms of survival with a reduction of acute GVHD.

Allogeneic stem cell transplantation after reduced-intensity conditioning for acute myeloid leukaemia: impact of chronic graft-versus-host disease.

The antineoplastic effect of allogeneic stem cell transplantation after reduced-intensity conditioning (RIC) relies on the graft-versus-tumour (GvT) reaction. GvT is closely linked to the development of graft-versus-host disease (GvHD). The incidence of acute GvHD after RIC seems lower than after myeloablative conditioning (MAC), whereas the incidence of chronic GvHD after RIC seems similar to after MAC. The results of RIC for acute myeloid leukaemia show a non-relapse mortality of approximately 15% at one year, a relapse incidence of approximately 40% after a median of 4-6 months, translating into overall and disease-free survival rates of 40-60%. The factors associated with improved outcome in most studies are the stage of the disease at transplantation, age and the development of chronic GvHD (and thus GvT). In a recent report, chronic GvHD was the most important factor associated with prolonged survival. Future efforts should be directed at aiming to decrease relapse rates. For this purpose, an adequate identification of high-risk patients, close monitoring of minimal residual disease after the procedure, and the use of antineoplastic drugs or immunotherapy may be of help.