Outcome Of Allogeneic Transplantation Research Articles

Impact of donor marrow cellularity on outcome of allogeneic stem cell transplantation

BackgroundOutcomes of allogeneic hematopoietic stem cell transplant (HSCT) are affected by a number of donor and patient related factors like extent of human leucocyte antigen mismatch, age, source of stem cells, female donor to male recipient and stem cell dose. All of these factors have been extensively investigated; however, effect of donor bone marrow cellularity on HSCT outcomes has not been evaluated. MethodsThis was a prospective study carried out at Armed forces bone marrow transplant center (AFBMTC/NIBMT) from January 2018 to December 2022. Bone marrow cellularity of donors was determined by separate assessment by two experienced Hematopathologists and classified as normocellular, hypocellular or hypercellular according to donor age. Total nucleated cells (TNC) were assessed by automated hematology analyzer and stem cell quantification was done by flowcytometric assay based on CD34, CD45 and 7-AAD immunophenotyping markers. Primary outcome measures were time to achieve neutrophil and platelet engraftment. Secondary outcome measures assessed were overall survival (OS), disease free survival (DFS) and graft versus host disease (GVHD). Frequency and percentage were calculated for categorical variables while Chi-square test was used for quantitative variables. Multivariate Cox regression analysis was used to determine significance of different variables and effect of cellularity on them. Kaplan Meier estimates with group differences were calculated using log rank tests for OS and DFS. A p value of 0.05 or less was considered statistically significant. ResultsCellularity of 95 donors was assessed, 39 (41.1 %) had normocellular marrow while 56 (58.9 %) were hypocellular for age. Median time from diagnosis to transplant was 13 months. In 38 (40 %) the indication for donation was for patients with bone marrow failure syndromes, 23 (24.2 %) for hematological malignancies, 21(22.1 %) for beta thalassemia major and 13 (13.6 %) for miscellaneous disorders including immune deficiencies. Median stem cell / CD 34 dose was 6 × 106/kg and median TNC dose was 5.09 × 108/kg. Median time of neutrophil engraftment was 13.6 days while that of platelet engraftment was 27.1 days. Mean OS was 84.2 %. OS for normocellular donors was 84.6 % and that for hypocellular donors was 83.9 % (p 0.995). DFS for normocellular donors was 84.6 % and for hypocellular donors was 83.9 % (p 0.96). No statistically significant association between the disease group and transplant type with donor marrow cellularity (p value 0.32 and 0.358 respectively) was determined. Multivariate logistic regression model and Backwald test showed no significant association between donor marrow cellularity and CD 34 dose (p 0.65), TNC (p 0.78), neutrophil engraftment (p 0.23), platelet engraftment (p 0.27), Acute GVHD (p 0.83), and chronic GVHD (p 0.44). ConclusionMajority of the donors had hypocellular bone marrow. Bone marrow cellularity had no statistically significant impact on the CD34 and TNC doses obtained; neither did it affect post-transplant neutrophil and platelet engraftment, OS, and DFS. Further population-based studies are required to confirm normal marrow cellularity in Pakistani population and the effects of various genetic and environment factors that make it hypocellular.

400.5: Relation between primary graft function and 5-year outcomes of islet allogeneic transplantation in type 1 diabetes: a retrospective cohort study in 1210 participants from the Collaborative Islet Transplant Registry

400.5: Relation between primary graft function and 5-year outcomes of islet allogeneic transplantation in type 1 diabetes: a retrospective cohort study in 1210 participants from the Collaborative Islet Transplant Registry

The results of therapy with venetoclax, daratumumab and plerixafor as part of the conditioning regimen in chemotherapy-refractory acute leukemia in children

The main outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) in chemotherapy-refractory acute leukemia remain suboptimal due to a high relapse rate. The incorporation of targeted anti-leukemia agents into the conditioning regimens is a potential approach to improve the efficacy of HSCT. We assessed the safety and potential efficacy of the addition of venetoclax, daratumumab, and plerixafor to the conditioning regimens in children with chemotherapy-refractory acute leukemias who received allogeneic TCRab/CD19-depleted HSCT. We used data from a pilot study, as well as the data of patients from a retrospective cohort who received similar therapy according to the individual indications. The study was approved by the Independent Ethics Committee and the Scientific Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology. All 43 patients (33 acute myeloid leukemias (AML), 8 T-cell acute lymphoblastic leukemias (T-ALL) and 2 acute leukemias of ambiguous lineage) had active disease status at the time of transplantation. The preparative regimen included myeloablative conditioning based on either total body irradiation or treosulfan or melphalan. A haploidentical related donor was used as a graft source in 38 cases, while a fully matched related or unrelated donor was used in 5 cases. The engraftment was observed in 93% of cases, no excessive toxicity was noted. MRD-negative complete remission was achieved in 37 patients (86%). The cumulative incidence of grade II–IV acute graft-versus-host disease (GvHD) was 10%, and the cumulative incidence of chronic GvHD was 5%. At 2 years, transplant-related mortality was 7%, relapse incidence was 52%, event-free survival was 41%, and overall survival was 51%. The overall survival rate for the AML group was 58% and 25% for the T-ALL group. Our data show that the addition of targeted agents to the conditioning regimens is safe, however, does not significantly improve the results of HSCT in the study cohort of patients.

The association of intestinal microbiota diversity and outcomes of allogeneic hematopoietic cell transplantation: a systematic review and meta-analysis.

Growing evidence suggests that highly intestinal microbiota diversity modulates host inflammation and promotes immune tolerance. Several studies have reported that patients undergoing allo-HSCT have experienced microbiota disruption that is characterized by expansion of potentially pathogenic bacteria and loss of microbiota diversity. Thus, the primary aim of this meta-analysis was to determine the association of intestinal microbiota diversity and outcomes after allo-HSCT, and the secondary aim was to analyze the associations of some specific microbiota abundances with the outcomes of allo-HSCT. Electronic databases of Pubmed, Embase, Web of Science, and Cochrane Library were searched from inception to August 2023, and 17 studies were found eligible. The pooled estimate suggested that higher intestinal microbiota diversity was significantly associated with overall survival (OS) benefit (HR = 0.66, 95% CI: 0.55-0.78), as well as decreased risk of transplant-related mortality (HR = 0.56, 95% CI: 0.41-0.76), and lower incidence of grade II-IV aGVHD (HR = 0.41, 95% CI: 0.27-0.63). Furthermore, higher abundance of Clostridiales was associated with a superior OS (HR = 0.40, 95% CI: 0.18-0.87), while higher abundance of Enterococcus (HR = 2.03, 95% CI: 1.55-2.65), γ-proteobacteria (HR = 2.82, 95% CI: 1.53-5.20), and Candida (HR = 3.80, 95% CI: 1.32-10.94) was an adverse prognostic factor for OS. Overall, this meta-analysis highlights the protective role of higher intestinal microbiota diversity on outcomes after allo-HSCT during both pre-transplant and post-transplant periods. Some specific microbiota can be useful in the identification of patients at risk of mortality, offering new tools for individualized pre-emptive or therapeutic strategies to improve allo-HSCT outcomes.

Cytomegalovirus Infection after Allogeneic Hematopoietic Cell Transplantation under 100-Day Letermovir Prophylaxis: A Real-World 1-Year Follow-Up Study.

The prevention and management of cytomegalovirus (CMV) reactivation is important to improve the outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) recipients. The aim of this study was to analyze real-world data regarding the incidence and characteristics of CMV infections until 1 year after allo-HCT under 100-day letermovir prophylaxis. A single-center retrospective study was conducted between November 2020 and October 2021. During the study period, 358 patients underwent allo-HCT, 306 of whom received letermovir prophylaxis. Cumulative incidence of clinically significant CMV infection (CS-CMVi) was 11.4%, 31.7%, and 36.9% at 14 weeks, 24 weeks, and 1 year post-HCT, respectively. Through multivariate analysis, the risk of CS-CMVi increased with graft-versus-host disease (GVHD) ≥ grade 2 (adjusted odds ratio 3.640 [2.036-6.510]; p < 0.001). One-year non-relapse mortality was significantly higher in letermovir breakthrough CS-CMVi patients than those with subclinical CMV reactivation who continued receiving letermovir (p = 0.002). There were 18 (15.9%) refractory CMV infection cases in this study population. In summary, letermovir prophylaxis is effective at preventing CS-CMVi until day 100, which increased after the cessation of letermovir. GVHD is still a significant risk factor in the era of letermovir prophylaxis. Further research is needed to establish individualized management strategies, especially in patients with significant GVHD or letermovir breakthrough CS-CMVi.

Outcomes of Allogeneic Stem Cell Transplant in Chronic Myeloid Leukaemia - A Single-Centre Experience from Pakistan

Objective: To determine indications and outcomes of stem cell transplant in Chronic Myeloid Leukemia in a tertiary care centre in Pakistan. &#x0D; Study Design: Retrospective longitudinal study&#x0D; Place and Duration of Study: Armed Forces Bone Marrow Transplant Center, Rawalpindi Pakistan, from Jan 2002 to Jan 2019.&#x0D; Methodology: Retrospective analysis of all the patients who had undergone transplants for chronic myeloid leukaemia at our centre from 2002 to 2019 was done. Cases enrolled included patients of both genders and any age for whom data related to disease status and follow-up post-transplant was available. Patients with incomplete records and follow-ups were excluded from the study.&#x0D; Results: Out of 73 patients, data from 53 patients was analyzed. At a median follow-up of 40 months, overall survival was 72%. Survival in patients &lt;40 years was better (78%) compared to the &gt;40 years (50%). Among the three conditioning regimens, Bu16Cy120 was the most commonly used (n=35, 66%) and had better overall survival (n=29, 83%) though statistical significance could not be established (p=0.172).&#x0D; Conclusion: In addition to the established indications of resistance or intolerance to tyrosine kinase inhibitors for bone marrow transplant in CML, the non-availability/ affordability, young age, and lack of access to novel drugs can be included in underdeveloped countries like Pakistan.

Long-term outcomes of allogeneic stem cell transplant in multiple myeloma

Allogeneic stem cell transplant (allo SCT) for multiple myeloma (MM) is potentially curative in some, while toxic in many others. We retrospectively analyzed 85 patients diagnosed with MM who underwent allo SCT as frontline or salvage therapy between 2000 and 2022 at Mayo Clinic Rochester and examined patient outcomes and prognostic markers. Overall survival (OS), progression free survival (PFS), treatment related mortality (TRM), and relapse rates (RR) were estimated using the Kaplan Meier method and competing risk models. Median follow-up was 11.5 years. Median OS and PFS were 1.7 and 0.71 years, respectively. Five-year OS and PFS were 22.2% and 15.1%, respectively. One-year TRM was 23.5%. Twelve patients demonstrated durable overall survival, living 10+ years beyond their allo SCT. This subgroup was more likely to have no or one prior auto SCT (p = 0.03) and to have been transplanted between 2000 and 2010 (p = 0.03). Outcomes were poor in this cohort with long follow-up, with few patients surviving 5 years or more, and most relapsing or dying within 2 years. We would expect better outcomes and tolerability with an expanded array of novel therapeutics and would prefer them to allo SCT.

Poor outcome of allogeneic transplantation for therapy-related acute myeloid leukemia induced by prior chemoradiotherapy.

Therapy-related acute myeloid leukemia (t-AML) is a therapeutic challenge as a late complication of chemotherapy (CHT) and/or radiotherapy (RT) for primary malignancy. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) presents itself as a curative approach. To establish the optimal allo-HSCT strategy for t-AML, we evaluated the relationship between characteristics of primary malignancy and allo-HSCT outcomes. Patients with t-AML or de novo acute myeloid leukemia (AML) who underwent first allo-HSCT in Japan from 2011 to 2018 were identified using a nationwide database. The detailed background of t-AML was obtained by additional questionnaires. Multivariate analysis and propensity score matching (PSM) analysis were performed to detect the prognostic factors associated with t-AML and compare outcomes with de novo AML. We analyzed 285 t-AML and 6761 de novo AML patients. In patients with t-AML, receiving both CHT and RT for primary malignancy was an independent poor-risk factor for relapse and overall survival (OS) (hazard ratio (HR) 1.62; p = 0.029 and HR 1.65; p = 0.009, reference: CHT alone group), whereas other primary malignancy-related factors had no effect on the outcome. Compared to the CHT alone group, complex karyotypes were significantly increased in the CHT + RT group (86.1% vs. 57.5%, p = 0.007). In the PSM cohort, t-AML patients with prior CHT and RT had significantly worse 3-year OS than those with de novo AML (25.2% and 42.7%; p = 0.009). Our results suggest that prior CHT and RT for primary malignancy may be associated with increased relapse and worse OS of allo-HSCT in t-AML.

Racial disparities in the outcomes of allogeneic bone marrow transplant: A 5-year nationwide inpatient study.

e19060 Background: Allogeneic bone marrow transplantation (ABMT) is a life-saving procedure in hematological malignancies and bone marrow failure disorders. Despite advances in the field, literature proposes racial disparities in the outcomes of ABMT. This study aims to investigate this difference among distinct racial cohorts. Methods: We identified patients who underwent ABMT for malignant and nonmalignant hematologic diseases from 2016-2020 using the nationwide inpatient sample (NIS) database. We compared the racial differences in outcomes during the hospitalization, including immunologic and hematologic complications, associated infections, length of stay, and mortality rate. Baseline characteristics were compared using a T-test and Chi-Square. Multivariate regression analysis was applied to estimate differences in outcomes. We used STATA Version 17.0 Software for data analysis. The p-value was set at p &lt; 0.05 for statistical significance. Results: A retrospective study was conducted on a cohort of 14,599 adults who underwent ABMT. Out of which 30% (4,379) developed complications. The mean age for ABMT was 54, and the average length of stay was 29 days. In this cohort, 79.5% (11,325) were whites, 4.2% (610) were blacks, 8.3% (1,185) were Hispanics, and 7.8% (1,125) were others. When comparing the outcomes among racial groups, invasive fungal infections 15.5% (95), mucositis 36% (220), septic shock 9% (55), and respiratory failure 14.7% (90) were more common in blacks (p &lt; 0.05). Neutropenia 41.3% (490) and cytomegalovirus (CMV) infection 12.2% (145) were more common in Hispanics (p &lt; 0.05). However, no significant difference was noted in immunologic complications (graft versus host disease (GVHD), bone marrow rejection (BMR), bone marrow failure (BMF)), pancytopenia, clostridium difficile infection (CDI), and mortality (p &lt; 0.05). Conclusions: Our study shows that blacks had a higher prevalence of invasive fungal infections, mucositis, septic shock, and respiratory failure, while Hispanics reported a higher prevalence of neutropenia and CMV infection. However, no significant differences were noted in GVHD, BMR, BMF, pancytopenia, CDI, and mortality rates. Therefore, it can be concluded that while there are some differences in post-ABMT complications among racial groups, overall, the rates of major complications and mortality do not significantly differ.

The impact of epigenetic modifications on allogeneic hematopoietic stem cell transplantation.

The field of epigenetics studies the complex processes that regulate gene expression without altering the DNA sequence itself. It is well established that epigenetic modifications are crucial to cellular homeostasis and differentiation and play a vital role in hematopoiesis and immunity. Epigenetic marks can be mitotically and/or meiotically heritable upon cell division, forming the basis of cellular memory, and have the potential to be reversed between cellular fate transitions. Hence, over the past decade, there has been increasing interest in the role that epigenetic modifications may have on the outcomes of allogeneic hematopoietic transplantation and growing enthusiasm in the therapeutic potential these pathways may hold. In this brief review, we provide a basic overview of the types of epigenetic modifications and their biological functions, summarizing the current literature with a focus on hematopoiesis and immunity specifically in the context of allogeneic hematopoietic stem cell transplantation.

Long-term outcome of second allogeneic hematopoietic stem cell transplantation (HSCT2) for primary graft failure in patients with acute leukemia in remission: A study on behalf of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

Second transplantation (HSCT2) is a potential treatment for primary graft failure (pGF). We assessed the outcome of HSCT2, performed between 2000 and 2021, for pGF in 243 patients with acute leukemia. Median age was 44.8 years. Conditioning at first HSCT (HSCT1) was myeloablative (MAC) in 58.4%. Median time from HSCT1 to HSCT2 was 48 days. Donors for HSCT2 were the same as for HSCT1 in 49%. Engraftment post HSCT2 was achieved by 73.7% of patients. The incidence of acute (a) graft versus host disease (GVHD) grades II-IV and III-IV was 23.2 and 8.1%. 5-year total and extensive chronic (c) GVHD was 22.3 and 10.1%. 5-year nonrelapse mortality (NRM), relapse incidence (RI), leukemia-free survival (LFS), overall survival (OS) and GVHD free, relapse-free survival (GRFS) was 51.6, 18.8, 29.6, 30.7 and 22.4%, respectively. Infections were the main cause of death. In multivariable analysis, being transplanted at second vs. first remission, lower Karnofsky performance status (KPS; <90) and receiving MAC at HSCT1 were adverse prognostic factors for NRM, LFS, OS, and GRFS, as was increased age for NRM, LFS, OS. We conclude that HSCT2 can rescue about a third of the patients who experienced pGF, but NRM is as high as 50%.

Impact of Public Reporting of Center-Specific Survival Analysis Scores on Patient Volumes at Hematopoietic Cell Transplant Centers

The Center for International Blood and Marrow Transplant Research reports the outcomes of allogeneic hematopoietic cell transplantation (alloHCT) at United States transplantation centers (TC) annually through its Center-Specific Survival Analysis (CSA). The CSA compares the actual 1-year overall survival (OS) and predicted 1-year OS rate after alloHCT at each TC, which is then reported as 0 (OS as expected), −1 (OS worse than expected), or 1 (OS better than expected). We evaluated the impact of public reporting of TC performance on their alloHCT patient volumes. Ninety-one TCs that serve adult or combined adult and pediatric populations and had CSA scores reported for 2012–2018 were included. We analyzed prior-calendar-year TC volume, prior-calendar-year CSA score, whether the CSA score had changed in the prior year from two years earlier, calendar year, TC type (adult only vs. combined adult and pediatric), and years of alloHCT experience for their impact on patient volumes. A CSA score of −1, as compared with 0 or 1, was associated with an 8% to 9% reduction in the mean TC volume (P < 0.001) in the subsequent year, adjusting for the prior year center volume. Additionally, being a TC neighboring an index TC with a −1 CSA score, was associated with a 3.5% increase in mean TC volume (P = 0.04). Our data show that public reporting of CSA scores is associated with changes in alloHCT volumes at TCs. Additional investigation into the causes of this shift in patient volume and the impact on outcomes is ongoing.

Outcomes of allogeneic or autologous stem cell transplantation followed by maintenance chemotherapy in adult patient with B-ALL in CR1 with no detectable minimal residual disease.

Autologous haematopoietic stem cell transplantation (auto-HSCT) as a treatment for B-cell acute lymphoblastic leukaemia (B-ALL) has been rigorously debated in recent years. We retrospectively analysed the outcomes of 355 adult patients with B-ALL in first complete remission who had received auto-HSCT or allogeneic HSCT (allo-HSCT) in our centre. The treatment efficacy was evaluated from a model stratified on the risk classification and minimal residue disease (MRD) status after three chemotherapy cycles. Auto-HSCT demonstrated comparable 3-year overall survival (OS) (72.7% vs. 68.5%, p = 0.441) and leukaemia-free survival rates (62.8% vs. 56.1%, p = 0.383) compared to allo-HSCT for patients with negative MRD, while the advantage of lower non-relapse mortality (1.5% vs. 25.1%, p < 0.001) was offset by a higher cumulative incidence of relapse (CIR) rates (35.7% vs. 18.9%, p = 0.018), especially in high-risk patients. For patients at high risk and with positive MRD, there was a lower trend of 3-year OS (50.0% vs. 66.0%, p = 0.078) and significantly higher CIR rates (71.4% vs. 39.1%, p = 0.018) in auto-HSCT. However, no significant interaction was observed in the tests. In conclusion, auto-HSCT appears to be an attractive treatment for patients with negative MRD after three chemotherapy cycles. For MRD-positive patients, allo-HSCT may be a more effective treatment.

Association between primary graft function and 5-year outcomes of islet allogeneic transplantation in type 1 diabetes: a retrospective, multicentre, observational cohort study in 1210 patients from the Collaborative Islet Transplant Registry

Allogeneic islet transplantation is a validated therapy in type 1 diabetes; however, there is decline of transplanted islet graft function over time and the mechanisms underlying this decline are unclear. We evaluated the distinct association between primary graft function (PGF) and 5-year islet transplantation outcomes. In this retrospective, multicentre, observational cohort study, we enrolled all patients from the Collaborative Islet Transplant Registry who received islet transplantation alone (ITA recipients) or islet-after-kidney transplantation (IAK recipients) between Jan 19, 1999, and July 17, 2020, with a calculable PGF (exposure of interest), measured 28 days after last islet infusion with a validated composite index of islet graft function (BETA-2 score). The primary outcome was cumulative incidence of unsuccessful islet transplantation, defined as an HbA1c of 7·0% (53 mmol/mol) or higher, or severe hypoglycaemia (ie, requiring third-party intervention to correct), or a fasting C-peptide concentration of less than 0·2 ng/mL. Secondary outcomes were graft exhaustion (fasting C-peptide <0·3 ng/mL); inadequate glucose control (HbA1c ≥7·0% [53 mmol/mol] or severe hypoglycaemia); and requirement for exogenous insulin therapy (≥14 consecutive days). Associations between PGF and islet transplantation outcomes were explored with a competing risk analysis adjusted for all covariates suspected or known to affect outcomes. A predictive model based on PGF was built and internally validated by using bootstraps resampling method. In 39 centres worldwide, we enrolled 1210 patients with a calculable PGF (of those without missing data, mean age 47 years [SD 10], 712 [59·5%] were female, and 865 (97·9%) were White), who received a median of 10·8 thousand islet-equivalents per kg of bodyweight (IQR 7·4-13·5). 986 (82·4%) were ITA recipients and 211 (17·6%) were IAK recipients. Of 1210 patients, 452 (37·4%) received a single islet infusion and 758 (62·6%) received multiple islet infusions. Mean PGF was 14·3 (SD 8·8). The 5-year cumulative incidence of unsuccessful islet transplantation was 70·7% (95% CI 67·2-73·9), and was inversely and linearly related to PGF, with an adjusted subhazard ratio (sHR) of 0·77 (95% CI 0·72-0·82) per 5-unit increase of BETA-2 score (p<0·0001). Secondary endpoints were similarly related to PGF. The model-adjusted median C-statistic values of PGF for predicting 5-year cumulative incidences of unsuccessful islet transplantation, graft exhaustion, inadequate glucose control, and exogenous insulin therapy were 0·70 (range 0·69-0·71), 0·76 (0·74-0·77), 0·65 (0·64-0·66), and 0·72 (0·71-0·73), respectively. This global multicentre study reports a linear and independent association between PGF and 5-year clinical outcomes of islet transplantation. The main study limitations are its retrospective design and the absence of analysis of complications. Public Health Service Research, National Institutes of Health, Juvenile Diabetes Research Foundation International, Agence National de la Recherche, Fondation de l'Avenir, and Fonds de Dotation Line Renaud-Loulou Gasté.

Long-term health outcomes of allogeneic hematopoietic stem cell transplantation.

Fifty years of hematopoietic cell transplantation (HCT) has ushered in an exciting era of cellular therapy and has led to enormous progress in improving the outcomes of patients with both malignant and non-malignant hematologic disease. As the survival of transplanted patients has increased, so has the recognition of long-term complications related to this therapy. The goal of this review is to highlight some of the most common long-term complications of HCT. To this end, we have conducted a review of the published literature on the long-term complications of HCT encompassing the past 50 years. We have endeavored to include long-term complications reported in research articles, case series and case reports, reviews, and abstracts. We have focused primarily on adult allogeneic HCT, but have included some data from studies of pediatric allogeneic HCT as well. We have also prioritized the literature published in the last 15 years. Key data supporting the onset and prevalence of the most common long-term complications was extracted. While the list of long-term complications extracted and reported was comprehensive, it was not exhaustive. We have endeavored to highlight some of the most common long-term complications of HCT, the recognition and management of which constitutes an important part of HCT survivorship care.

Abstract 643: Correlations of dietary fiber with intestinal microbiome and outcomes in allogeneic hematopoietic cell transplantation

Abstract Background: Allogeneic hematopoietic cell transplantation (allo-HCT) can be a curative therapy for patients with hematological malignancies. However, allo-HCT poses a significant risk for post-transplant mortality due to graft-versus-host disease (GVHD), which is associated with loss of beneficial intestinal microbiota and decrease of microbial metabolites. In addition, dietary fiber can modulate the intestinal microbiome and the production of short-chain fatty acids (SCFAs), which are microbial metabolites associated with intestinal homeostasis. Therefore, we hypothesized that a high-fiber diet is associated with an increase of beneficial commensals, higher concentrations of SCFAs, and decreased risk of GVHD. Methods: We collected dietary data and fecal samples from 73 allo-HCT patients (GVHD n=45, No-GVHD n=28) at Memorial Sloan Kettering Cancer Center, collected longitudinally throughout the allo-HCT course, and performed 16s rRNA, shotgun metagenomic sequencing, and gas chromatography mass spectrometry (n=311). We assessed the α-diversity, microbiome composition, and concentrations of fecal SCFAs in response to fiber intake. We also tested different concentrations of dietary fiber (0%, 6%, 12% and 40%) in a preclinical GVHD model (C57BL/6J into BALB/c, n=30 per group, n=180 total) and assessed GVHD lethality and fecal microbial composition. Results: We found that in allo-HCT patients, fiber intake significantly correlated with microbial α-diversity (R=0.3, p=0.01) and patients with a higher fiber diet had a significantly higher microbial α-diversity when compared to the low fiber cohort (p&amp;lt;0.001). Remarkably, the decrease in dietary fiber post-allo-HCT correlated with a significant reduction in the fecal concentrations of SCFAs in the GVHD group (n=14), butyrate (p=0.003), propionate (p=0.01), and acetate (p=0.004), that was not significant in the No-GVHD cohort (n=28), indicating that low dietary fiber could lead to lower production of bacterial metabolites in GVHD. In addition, mice receiving a fiber-rich diet (12%) had a significant reduction in GVHD lethality (p=0.02) compared to mice receiving lower or higher fiber (0%, 6%, 40%). A 12% fiber diet also resulted in higher microbial α-diversity (p=0.02) and a significant decrease in Enterococcus faecalis (p=0.05), a pathogen associated with worse GVHD mortality in mice and humans. Conclusions: Our study demonstrates that a) higher fiber intake in patients after allo-HCT is associated with an increase in α-diversity and SCFA concentrations, and b) optimal fiber consumption in pre-clinical GVHD models leads to an increase in α-diversity, a decrease in pathogen mono-domination, and more importantly, a decrease in GVHD lethality. These results suggest that dietary fiber could be used in the prevention of GVHD. Citation Format: Jenny Paredes, Peter Adintori, Anqi Dai, Ruben J. Faustino Ramos, Teng Fei, Harold Elias, Marina Burgos da Silva, Romina Ghale, Charlotte Pohl, Justin Cross, Oriana Miltiadous, Marcel van den Brink. Correlations of dietary fiber with intestinal microbiome and outcomes in allogeneic hematopoietic cell transplantation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 643.

The Outcome of Allogeneic Bone Marrow Transplantation in Primary Myelofibrosis Vs other lines of treatment

The Outcome of Allogeneic Bone Marrow Transplantation in Primary Myelofibrosis Vs other lines of treatment

Impact of measurable residual disease on outcomes of unrelated donor haematopoietic cell transplantation with post-transplant cyclophosphamide in AML in first complete remission.

Pre-transplant measurable residual disease (MRD) predicts relapse and outcome of allogeneic haematopoietic cell transplantation (allo-HCT). The impact of MRD on the outcomes of post-transplant cyclophosphamide (PTCy)-based allo-HCT from a matched unrelated donor (UD) is unknown. This study assessed the impact of MRD in acute myeloid leukaemia (AML) in the first complete remission (CR1). A total of 272 patients (MRD negative [MRD-], n= 165; MRD positive [MRD+], n= 107) with a median follow-up of 19 (range: 16-24) months were studied. The incidence of grades II-IV and grades III-IV acute GVHD at day 180 was 25.2% and 25% (p= 0.99), and 10.6% and 6.8% (p= 0.29), respectively, and 2-year chronic GVHD was 35% and 30.4% (p= 0.96) in MRD+ and MRD- cohorts, respectively. In multivariate analysis, MRD+ status was associated with a higher incidence of relapse (RI) (hazard ratio [HR]=2.56, 95% CI: 1.39-4.72), lower leukaemia-free survival (LFS) (HR=2.04, 95% CI: 1.23-3.39), overall survival (OS) (HR=1.83, 95% CI: 1.04-3.25) and GVHD-free, relapse-free survival (GRFS) (HR=1.69, 95% CI: 1.10-2.58). MRD status did not have a significant impact on non-relapse mortality (NRM), or acute or chronic GVHD risk. Among patients with AML undergoing UD allo-HCT with PTCy, pre-transplant MRD+ status predicted a higher relapse rate, lower LFS, OS and GRFS.

Correction to: Impact of pre-transplant induction and consolidation cycles on AML allogeneic transplant outcomes: a CIBMTR analysis in 3113AML patients

Correction to: Impact of pre-transplant induction and consolidation cycles on AML allogeneic transplant outcomes: a CIBMTR analysis in 3113AML patients

The prognostic value of patient-reported outcomes in allogeneic hematopoietic stem cell transplantation: exploratory analysis of a randomized nutrition intervention trial

Whether patient-reported outcomes (PROs) can predict overall survival (OS) and non-relapse mortality (NRM) among recipients of allogeneic stem cell transplantation (allo-HSCT), is unclear. We performed an exploratory analysis of the prognostic value of patient-reported outcomes (PROs) among 117 recipients of allogeneic stem cell transplantation (allo-HSCT) who participated in a randomized nutrition intervention trial. Cox proportional hazards models were used to investigate possible associations between PROs collected pre-allo-HSCT (baseline) using scores from the EORTC Quality of Life Questionnaire-Core 30 (QLQ-C30) and 1-year overall survival (OS), whereas logistic regression was used to study associations between these PROs and 1-year non-relapse mortality (NRM). Multivariable analyses indicated that only the Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) and the European Bone Marrow Transplantation (EBMT) risk score were associated with 1-year OS. In the multivariable model including clinical-sociodemographic factors for 1-year NRM, our analysis showed that living alone (p=0.009), HCT-CI (p=0.016), EBMT risk score (p=0.002), and stem cell source (p=0.046) could be associated with 1-year NRM. Moreover, in the multivariable model, our analysis showed that only appetite loss from the QLQ-C30 was associated with 1-year NRM (p=0.026). In conclusion, in this specific setting, our analysis suggests that the commonly used HCT-CI and EBMT risk scores could be predictive for both 1-year OS and 1-year NRM, whereas baseline PROs in general were not.