Hematopoietic Stem Cell Transplantation Group Research Articles

Application of plasma metagenomic next-generation sequencing improves prognosis in hematology patients with neutropenia or hematopoietic stem cell transplantation for infection.

Metagenomic next-generation sequencing (mNGS) is a novel technique for detecting pathogens. This retrospective study evaluated the diagnostic value of mNGS using plasma for infections in hematology patients and its impact on clinical treatment and prognosis in different subgroups of hematology patients. A total of 153 hematology patients with suspected infection who underwent mNGS using plasma were enrolled in the study. Their clinical histories, conventional microbiological test (CMT) results, mNGS results, treatment and prognosis were retrospectively analyzed. In 153 plasma samples, mNGS yielded a higher positivity rate than CMT (total: 88.24% vs. 40.52%, P<0.001; bacteria: 35.95% vs. 21.57%, P < 0.01; virus: 69.93% vs. 21.57%, P<0.001; fungi: 20.26% vs. 7.84%, P<0.01). mNGS had a higher positivity rate for bacteria and fungi in the neutropenia group than in the non-neutropenia group (bacteria: 48.61% vs. 24.69%, P<0.01; fungi: 27.78% vs. 13.58%, P<0.05). mNGS demonstrated a greater advantage in the group of patients with hematopoietic stem cell transplantation (HSCT). Both the 3-day and 7-day efficacy rates in the HSCT group were higher than those in the non-HSCT group (3-day: 82.22% vs. 58.65%, P < 0.01; 7-day: 88.89% vs. 67.31%, P < 0.01), and the 28-day mortality rate was lower in the HSCT group than in the non-HSCT group (6.67% vs. 38.89%, P < 0.000). The neutropenia group achieved similar efficacy and mortality rates to the non-neutropenia group (7-day efficiency rate: 76.39% vs. 71.43%, P > 0.05; mortality rate: 29.17% vs. 29.63%, P > 0.05) with more aggressive antibiotic adjustments (45.83% vs. 22.22%, P < 0.01). mNGS can detect more microorganisms with higher positive rates, especially in patients with neutropenia. mNGS had better clinical value in patients with hematopoietic stem cell transplantation (HSCT) or neutropenia, which had a positive effect on treatment and prognosis.

Is Allogeneic Hematopoietic Stem Cell Transplant (HCT) in First Remission Beneficial to Acute Myeloid Leukemia (AML) Patients with Isocitrate Dehydrogenase(IDH) Mutations?

Introduction Somatic mutations in the isocitrate dehydrogenase 1 and 2 genes (IDH1 and IDH2) are relatively frequent in acute myeloid leukemia (AML) but with heterogeneous prognoses. The prognostic impact of this AML subtype with IDH mutations may be influenced by the comutational status with other somatic mutation, the specific types of IDH1/2 mutation (ie, IDH1 R132, IDH2 R140, and IDH2 R172). Allogeneic stem cell transplant allogeneic HCT represents a curative option for subgroups of AML patients (pts), but not for all subtypes. Transplant referral is made based on the ELN risk group classified into favorable, intermediate, and adverse risk. Although many AML pts with IDH1/2 mutations are referred to allogeneic hematopoietic stem cell transplantation (HCT) and transplanted, however it is not fully elucidated whether allogeneic HCT brings definite survival benefit to this group of the pts. Statistical attention is to be paid to the time to HCT from CR1 achievement. Before HCT, the case should be counted as a case of no HCT, while after HCT this case can be accounted as the case received HCT using the Mantel-Byar test (MBT). To handle immortal time bias, the Mantel-Byar method was used to depict outcomes during the follow-up period. Kaplan-Meier curves were avoided as they can introduce immortal bias, considering the period of time before treatment as part of the treatment arm. Instead, the MBT and landmark methods were employed to address this issue. Allogeneic HCT was treated as a time-dependent variable to prevent immortal bias. The aim of the present study is to identify if AML pts with IDH mutations obtain survival benefit from allogeneic HCT in CR1 using HCT as a time-dependent covariate with using Mantel-Byar test. Patients &amp; Method We conducted a retrospective study that included 1,228 adult pts who were diagnosed with AML and achieved CR1 in 5 centers (Toronto, Vancouver, and Montreal, Canada; Hwasun and Seoul, South Korea) from January 1997 to January 2020. Next-generation sequencing was performed in each institution according to their own standard targeted sequencing panel. We considered allogeneic HCT in CR1 as a time-dependent covariate and used a Mantel-Byar test to avoid immortal bias. Relapse-free survival (RFS) was selected for the primary endpoint, defined as the time from CR1 to relapse or death from any cause. EZR software version 1.41 was used throughout the study for statistical analysis. Results Out of 1228, a total of 238 pts (19.4%) was found to have IDH1/2 mutation, among whom 92 pts (38.6%) had isolated IDH1 mutations, 140 pts (58.8%), isolated IDH2 mutations, and 6 pts (2.5%) having coexistence of IDH1 and IDH2 mutations. With a median follow-up duration of 20.8 months (mo) (1-194.3 mo) among survivors after achieving CR1, 91 pts died while 115 pts experienced relapse. One hundred twenty-one pts received HCT in CR1, and 44 pts relapsed after HCT. The 2-year overall survival of those 238 pts was 58.9% (51.3-65.6), and 2-yr RFS was48.9% (41.6-55.8) Between the HCT (n=121) vs non-HCT group (n=117), there were no differences in sex, cytogenetic risk or other somatic mutation except NPM1 mutation which was more frequently detected in the non-HCT group (p =0.002). As expected, the HCT group was younger (55 years (15-74 yrs)) than non-HCT group (62 years (27-82 yrs), p&amp;lt;0.001). First, the RFS and OS was compared between HCT vs non-HCT groups considering HCT as non-time dependent covariate. The 2-year RFS rate was higher in the HCT group (61.0%) compared to the non-HCT group (37.0%, p= 0.0002). However, it was not translated into superior OS in the HCT group: 2-year OS rate, 64.4% in the HCT group vs 53.7% in the non-HCT group, p=0.1). We have conducted time-dependent analysis taking taken HCT in CR1 into account as a time-dependent (td) covariate using MBT. The trend of superior RFS in HCT group was reproduced in MBT: HCT in CR1 was found to improve RFS (Hazard ratio [(HR) of 0.62, (95% C.I. [0.42-0.92]; p=0.02)] as shown in Fig.1B utilizing Simon-Makuch plot. However, Multivariate analysis (MVA) for RFS did not confirm HCT in CR1 as an independent prognostic factor for RFS, while Following factors were found to be associated with RFS adversely: age &amp;gt; 60 years, presence of DNMT3A mutation, and presence of IDH1 mutation. Conclusion Allogeneic HCT in CR1 could bring some survival benefit on RFS in AML pts with IDH1/2 mutation, but not confirmed in MVA. Further study is warranted to reach a clearer conclusion with larger number of

Similar Overall Survival and Event-Free Survival for Patients Under or over the Age of 14 Years, but More Chronic Graft Versus Host Disease and Non-Relapse Mortality in the “Older” Patients

Purpose: In the prospective, randomized, multinational FORUM trial, total body irradiation and etoposide were statistically more effective than chemoconditioning (Peters et al, JCO 2021; FORUM study; EudraCT: 2012-003032-22; ClinicalTrials.gov: NCT01949129). The multivariate analysis in this cohort showed an inferior overall survival (OS) for patients (pts) over the age of 10 years, HR 1.8 (95% CI, p=0.048). To update these findings, we examine the impact of age at allogeneic hematopoietic stem cell transplantation (HSCT), we analyzed 791 FORUM pts who received TBI and etoposide as conditioning regimen between April 2012 and March 2022 and compared their outcomes according to different age categories. Patients and Methods: Almost all patients were transplanted in second or first complete remission (CR2) (47%, n=370; CR1: 46%, n=361, &amp;gt;CR3: 8%, n=59), from matched unrelated donors (MUD) 70%, n=552, HLA-identical sibling donors (MSD) 30%, n=239, bone marrow (BM) 70%, n=551, or cord blood (CB) 3%, n=26. Median age at HSCT was 10 years (4-21). Median observation time was 2.3 years (0.3 to 8) (Table 1: Basic Characteristics). The conditioning regimen consisted of total body irradiation (TBI) - 6 fractions of 2 Gy on 3 consecutive days followed by 60 mg/kg body weight etoposide (max 1800 mg/m2, total upper dose limit 3.6 g). GVHD prophylaxis was CSA only for MSD receiving bone marrow. ATG/CSA/MTX was used for the MUD HSCT group. Results: 127 evaluable pts were transplanted between 4-6 years (group 1), 249 between 6-10 years (group 2), 231 between 10-14 years (group 3), and &amp;gt; 14 years were 184 pts (group 4) (n.s.) By the 4 age groups, the 5-year OS was 0.83±0.04 (group 1), 0.75±0.04 (group 2), 0.75±0.04 (group 3), and 0.74±0.04 (group 4), respectively, p = 0.133. Five-year event-free survival (EFS) was also similar for all age groups: 0.71 ± 0.06, 0.72 ± 0.04, 0.66 ± 0.05, 0.69 ± 0.04 (p=0.611): Figure 1. The three-year cumulative relapse incidences (CIR) were 0.23±0.04, 0.19±0.03, 0.14±0.03, and 0.17±0.03, respectively (p=0.286). Non-relapse mortality (NRM) was significantly lower in the two younger age groups (0.02 ± 0.01 group 1 and 0.05 ± 0.02 group 2) compared to 0.11 ± 0.02 in both older age groups (p = 0.047). The primary causes of death in the 18/184 pts in group 4 were as follows: infections (fungal, viral, bacterial): n=8, acute and chronic graft versus host disease (aGVHD, cGVHD): n=3, sinusoidal obstruction syndrome, coagulopathies: n=4, multi-organ failure: n=3. Among the 767 evaluable pts, 503 (66%) had no or grade1 aGVHD, 188 (25%) had grade 2 aGVHD, and 76 pts (11%) had grade3 to 4 aGVHD; in patients &amp;gt; 14 years 22 (14%) had a grade 3 to 4 aGVHD (p = 0.624). The 3-year incidence of extensive cGVHD was significantly higher in pts older than 14 years (0.21±0.03 vs. 0.10±0.03, 0.11±0.02 and 0.14±0.03, respectively), which also translated into significantly better extensive cGVHD-free, relapse-free survival (cGRFS) for the younger cohorts (Table 1). To date, the overall incidence of secondary malignancies in this cohort is 0.01 (n = 11) with no significant differences in the 4 age categories. In the age group &amp;gt; 14 years, in 98 pts transplanted in first CR vs. &amp;gt; CR1 (n=86), 5-year OS is 0.83±0.04 and 0.63±0.06, respectively (p=0.005). Similarly, 5-year EFS was 0.79±0.05 and 0.56±0.07, respectively (p=0.002). In multivariate analysis, OS, EFS, CIR was not influenced by donor type and pts' age at transplant. However, NRM was higher in pts older than 14 years, the hazard ratio (HR) being 4.8 (1.4-16; p=0.012) as compared to patients aged 4-6 years. Remission status (CR1 vs. &amp;gt;CR1) had significant impact on EFS with HR of 1.6 (1.1-2.1; p= 0.004) and CIR (HR 1.7; 1.1-2.4; p= 0.012). Conclusions: In the FORUM trial, patients who underwent allogeneic HSCT from HLA-identical or HLA-matched unrelated donors older than 4 years and younger than 21 years who received myeloablative conditioning with TBI/etoposide had similar overall and event-free survival regardless of age at HSCT. The incidence of chronic GVHD and NRM was higher in patients &amp;gt; 14 years compared to younger patients.

Outcomes after Bone Marrow Versus Peripheral Blood Haploidentical Hematopoietic Stem Cell Transplantation Using Post-Transplant Cyclophosphamide-Based Gvhd Prophylaxis

Background: Patients who do not have a human leukocyte antigen (HLA)-matched donor can undergo hematopoietic stem cell transplantation (HSCT) by utilizing haploidentical (haplo) family donors and post-transplant cyclophosphamide (PTCy) for Graft-versus-host disease (GVHD) prophylaxis. Originally, Haplo transplants utilized a bone marrow (BM) source because of concern of higher incidence of GVHD with peripheral blood stem cells (PBSC) graft. Recent years have seen an increase in PBSC graft utilization. Some published studies have reported comparable survival between the two graft sources. These studies also reported lower rate of chronic GVHD and higher quality of life with BM and a lower relapse rate and faster engraftment with PBSCs. We aimed to investigate the outcomes following BM versus PBSC haplo HSCT using (PT-Cy)-based GVHD prophylaxis. Methods: In this single-center retrospective study, we included all (n=176) adult patients who underwent haplo HSCT from August 2016 to July 2021 and had at least one year of follow-up. Bivariate analyses, using the chi-square and t-test, were performed. Kaplan-Meier and regression analyses were conducted. Data were analyzed using SPSS version 28. Statistical significance was considered at p&amp;lt;0.05. Results: The study included 176 haplo transplants including 65% peripheral blood and 35% bone marrow grafts. The median age was 54 (18-74) years and 68% of recipients were males. Ethnic minorities comprised 30% of recipients. Hematologic diagnoses included myeloid disease (65%), lymphoid disease (29%), and others (6%). 31 % of the patients underwent a Myeloablative transplant. Hematopoietic cell transplantation comorbidity index of 3 or higher was noted in 53% of patients. With a Median follow-up 21 (0-73) months, Overall survival (OS) and disease-free survival (DFS) was not reached in either BM or PBSC haplo HSCT group. 1-year OS of 75% and 74% (p-0.898) and 1-year DFS of 63% and 63% (p-0.994) were noted in BM and PBSC group respectively. In PBSC versus BM haplo recipients, an earlier neutrophil engraftment (17 days vs 18 days, p=0.022) was seen. Similar incidences of grade II-IV acute GVHD (50% vs 51%, p=0.875), relapse (22% vs 26%, p=0.579), non-relapse mortality (NRM, 17% vs 20%, p=0.682), platelet engraftment (28 vs 31 days, p&amp;lt;0.092) and 1- year chronic GVHD (35% vs 38%, p=0.410) were noted. Conclusions: In this study, Haploidentical allogeneic hematopoietic stem cell transplant recipients demonstrated similar rates of overall and disease-free survival, relapse, non-relapse mortality, acute and chronic GVHD, and platelet engraftment regardless of graft source. Neutrophil engraftment was observed one day earlier in peripheral stem cell recipients. This supports the use of either PBSC or Bone marrow as the preferred source of Haploidentical transplants.

Acute Myeloid Leukemia (AML) Patients with Myelodysplasia (MDS) Related-Gene Mutations in First Complete Remission (CR1) Found to Have Benefit from Allogeneic Hematopoietic Stem Cell Transplant (HCT)

Introduction: Acute myeloid leukemia (AML) with myelodysplasia-related gene mutations is a new disease entity introduced in the International Consensus Classification of Myeloid Neoplasms 2022 (ICC 2022). Myelodysplasia-related gene mutations include ASXL1, BCOR, EZH2, RUNX1, SF3B1, SRSF2, STAG2, U2AF1, or ZRSR2 . Allogeneic hematopoietic stem cell transplant (HCT) represents a curative option for subgroups of AML patients, but not for all. In a prior study (Song et al.) reported the survival benefit of allogeneic HCT in 59 patients with AML with secondary type mutations (STM) including SRSF2, SF3B1, U2AF1, ZRSR2, ASXL1, EZH2, BCOR, and STAG2. Allogeneic HCT could abrogate adverse prognosis in AML with STMs, and reduce its mortality risk by 58% (Song et al. BMT 2022). In the present study, we aim to evaluate the frequency of this new disease entity of AML with MDS-related mutations and evaluate the prognostic impact of allogeneic HCT in patients with MDS-related mutations achieving CR1. For comparison of the benefit from HCT, the mantel-Byar test was applied to take into account time-dependent covariate of HCT in CR1 to avoid immortal bias. Patients and Methods: We conducted a retrospective study that included 1,228 adult patients who were diagnosed with AML from January 1997 to January 2020and achieved CR1 in 5 centers (Toronto, Vancouver, and Montreal, Canada; Hwasun and Seoul, South Korea). Next-generation sequencing was performed as their standard clinical practice using targeted sequencing panel in each institution. As defined in ICC 2022, AML with myelodysplasia-related gene mutations was defined as the case of AML with ASXL1, BCOR, EZH2, RUNX1, SF3B1, SRSF2, STAG2, U2AF1, or ZRSR2 mutation(s). We considered allogeneic HCT in CR1 as a time-dependent covariate and used a Mantel-Byar test to avoid immortal bias. We identified 278 pts (22.6%) who had at least one MDS-related gene mutation at diagnosis. Relapse-free survival (RFS) at 2 years was selected for the primary endpoint, defined as the time from CR1 to relapse or death from any cause. EZR software version 1.41 was used throughout the study for statistical analysis. Results: The median follow-up duration among survivors after achieving CR1 was 16.5 months (mo) (Range: 1.3-217.9 mo). Between the HCT vs non-HCT group, there were no differences in sex, cytogenetic risk or other somatic mutation except NPM1 mutation which was more frequently detected in non-HCT group (p &amp;lt;0.001). As expected, younger pts were more frequently noted in HCT group, p=0.001). First, considering HCT as non-time dependent covariate, we have compared RFS and OS between HCT vs non-HCT groups. The 1 year RFS rate was superior in the HCT group (77.7%) to that in non-HCT group (49.9%, p&amp;lt;0.0001; Fig.1A). A similar trend was noted for the 1-year OS rate presenting higher OS rate in the HCT group (83.8%) than in the non-HCT group (72.7%, p=0.0003). Next, when HCT in CR1 was taken into account as a time-dependent (td) covariate, Mantel-Byar analysis showed a consistent finding of superior RFS in HCT group to non-HCT group: time dependent covariate of HCT in CR1 was found to be favorable (Hazard ratio [(HR) of 0.45, (95% C.I. [0.31-0.65]; p=0.00003)] as shown in Fig.1B which is a Simon-Makuch plot. In multivariate analysis (MVA) for RFS, time-dependent covariate of HCT in CR1 retained its statistical significance, thus concluding that HCT in CR1 is an independent prognostic factor for RFS (HR: 0.44, 95% CI [0.29-0.68], p =0.0002) together with other variables found to be adverse on RFS including monosomal karyotype (p=0.03), IDH1 mutation (p=0.01), and age &amp;gt; 60 years (p=0.002); while CEBPA (p=0.02) and NPM1 (p=0.049) mutations were found to be favorable on RFS in MVA. Conclusion: In our cohort of 1228 AML patients, we have identified 278 AML patients with myelodysplasia-related gene mutations (22.6%). We have confirmed that allogeneic HCT in CR1 is strongly recommended in a subgroup of AML with myelodysplasia-related gene mutations based on the favorable impact of HCT in CR1 on RFS from the present study. This result supports the urgent referral of this patient group for allogeneic HCT in CR1.

The Presence of Somatic Mutations on Specific Pathways Such As Chromatin Modifier, Spliceosome, and Myeloid Transcription Factor at Diagnosis Was Found to Have Benefit from Allogeneic Hematopoietic Stem Cell Transplantation (HCT) in 1,228 Patients with Acute Myeloid Leukemia in First Complete Remission (CR1)

Introduction Allogeneic stem cell transplant (HCT) brings survival benefit to certain subgroups of acute myeloid leukemia (AML) patients, although it may not be suitable for all cases. Decision for HCT referral is based on the ELN risk grouping, which classifies pts into favorable, intermediate, and adverse risk categories. While HCT is recommended for pts in the intermediate and adverse risk, those in the favorable risk are deferred to receive HCT. However, currently, there is a lack of data directly demonstrating benefits of HCT in specific mutation groups. Patients and Method In this retrospective study, out of 1477 newly diagnosed AML pts 1,228 pts achieved CR1 and had undergone baseline next-generation sequencing (NGS) at diagnosis from January 1997 to January 2020. The data were collected from five different centers located in Toronto, Vancouver, and Montreal, Canada, as well as Hwasun and Seoul, South Korea. NGS was performed in each institution with each institution's standard targeted sequencing panel. To assess the effectiveness of HCT, particular attention will be given to the time from achieving complete remission 1 (CR1) to HCT. To handle immortal time bias, the Mantel-Byar method was used to depict outcomes during the follow-up period. Kaplan-Meier curves were avoided as they can introduce immortal bias, considering the period of time before treatment as part of the treatment arm. Instead, the MBT and landmark methods were employed to address this issue. Allogeneic HCT was treated as a time-dependent variable to prevent immortal bias. Gene mutations were grouped into 6 biologic pathways, including DNA methylation, chromatin modifiers, cohesion complex, activated signaling, tumor suppressor, spliceosome, and myeloid transcription factor (TF) mutations. In the multivariate (MVA) analysis, any mutations with a frequency of &amp;gt;5% were included as well as TP53 which has very grave prognosis. The primary objective of this study is to identify specific groups of AML pts who can derive significant benefits from receiving HCT in CR1, treating HCT as a time-dependent (td) covariate in the analysis. Statistical analyses were conducted using EZR version 1.41. Results The median duration of follow-up among survivors after achieving CR1 was 22.6 months (range: 1-217.9 months). Among the 593 pts, who underwent allogeneic HCT in CR1, the HCT group was composed of younger pts, with a median age of 50 years compared to 56 years in the non-HCT group (p &amp;lt; 0.001). Also, there were fewer pts with NPM1 mutation in the HCT group, accounting for 20.7% compared to 32.4% in the non-HCT group (p &amp;lt; 0.001). Apart from these characteristics, the two groups were similar in other parameters. The 2-year overall survival (OS) was higher in the HCT group, at 66.4%, compared to 54.6% in the non-HCT group (p &amp;lt; 0.0001). Similarly, the 2-year RFS was higher in the HCT group, with a rate of 64.8%, compared to 52.1% in the non-HCT group (p =1.82e-15). Furthermore, HCT as a time-dependent covariate was found to be favorable (Hazard ratio [HR] 0.76, 95% C.I. [0.63-0.91]; p=0.003), as demonstrated in the Simon-Makuch plot (p = 0.003). In the MVA, HCT as a time-dependent covariate retained its favorable impact on RFS (HR 0.67, [0.56-0.82]; p&amp;lt;0.0001). The MVA showed several prognostic factors besides HCT such as NPM1 and CEBPA mutations as favorable factors for RFS, being classified under the European Leukemia Network (ELN) favorable risk group. Conversely, FLT3-ITD, DNMT3A, IDH1, KIT, and TP53 mutations, monosomal karyotype, age &amp;gt; 60 years, and white blood count (WBC) at diagnosis &amp;gt; 55,600/mm^3 were associated with worse RFS. In terms of RFS, the greatest benefit of HCT was observed in the pts having mutations in ASXL1 (HR 0.34 [0.15-0.78]), BCOR (HR 0.29 [0.14-0.61]), IDH1/2 (HR 0.62 [0.42-0.92]), and RUNX1 (HR 0.17 [0.08-0.40]) but no significant benefit in those with KRAS (HR 1.59), NRAS (HR 1.21), PTPN11 (HR 1.23), and WT1 (HR 1.30). According to the biological pathway of somatic mutations, the greatest benefit of HCT in terms of RFS was observed in pts with mutations in the chromatin modifier (HR 0.37 [0.22-0.62]), spliceosome (HR 0.32 [0.16-0.65]), and myeloid TF pathway (HR 0.52 [0.34-0.79]). Conclusion Allogeneic HCT exerts a greater benefit on RFS in AML pts with mutations in the chromatin modifier, spliceosome, and myeloid TF pathways. Further study is warranted to replicate this finding.

Patient Characteristics and Outcomes of Sinusoidal Obstruction Syndrome with and without Hematopoietic Stem Cell Transplant

Introduction Sinusoidal obstruction syndrome (SOS), also called hepatic veno-occlusive disease (VOD) is a condition causing damage of hepatic vascular endothelial cells, it can progress to multi-organ failure and is associated with high mortality ( &amp;gt;80%). It is known to occur mainly after high dose chemotherapy use in hematopoietic stem cell transplant (HSCT) but with recent advances in chemotherapy, there is an increase in its incidence in non-hematopoietic stem cell transplant patients (non-HSCT). Currently, there is limited literature comparing the patient characteristics and survival of SOS in HSCT vs non-HSCT patients. Therefore we conducted this retrospective analysis. Methods We performed a retrospective analysis using the 2016-2020 National inpatient sample (NIS) database, generated by the Health care cost and utilization project (HCUP). We gathered data on all patients who had SOS/VOD during this time period. They were divided into two cohorts, those who received hematopoietic stem cell transplant (HSCT group) vs those who did not receive hematopoietic stem cell transplant (non-HSCT group). Among the two cohorts we compared the patients characteristics, underlying malignancies, comorbidities and mortality. Results From the NIS database during the study period 1740 cases had documented SOS/VOD. Of those, 520(30%) had a history of HSCT and 1220(70%) did not have HSCT. Of the 520 cases with HSCT, 135 (26%) had Acute lymphoblastic leukemia (ALL), 105 (20.2%) had Acute myeloid leukemia (AML), 55 (10.6%) had Non-Hodgkin lymphoma (NHL), 20 (3.8%) had Chronic myeloid leukemia (CML), 15 (2.9%) had Hodgkin lymphoma (HL), the rest were other malignancies which were not included in the search. Of the 1220 cases without HSCT, 320 (26.2%) had ALL, 150 (12.3%) had AML, 90 (7.4%) had Solid tumors, 55 (4.5%) had NHL, 15 (1.2%) had CML, 15 (1.2%) had HL, the rest were likely malignancies not included in the search. ALL was the predominant cancer in both HSCT and non-HSCT groups (26% and 26.2% respectively), followed by AML, with more AMLs noted in the HSCT group (20%) versus the non-HSCT group (12.3%). The study population predominantly consisted of Whites followed by Hispanics and then African-Americans in both groups. The population also consisted predominantly of males across both cohorts. (Table 1). The solid tumors which were associated with SOS in the non-HSCT group included colorectal cancer, liver cancer, pancreatic cancer and Breast cancer in that order (Table 2). Preexisting liver disease was present in 215 (17.6%) of patients in non-HSCT cohort vs 60 (11.5%) patients in SCT cohort. Pre-existing lung disease was insignificant in both groups. Mortality was compared between the two groups after adjusting for primary cancer, age, sex, race and we found that SCT group had higher odds of mortality compared to non-SCT (14.4% vs 7.4%, aOR 1.866, 95% CI 1.29-2.68, p&amp;lt;0.01). Further multivariate analysis could not be carried out due to low sample size. Discussion Although traditionally, SOS/VOD has been thought to be a complication related to SCT, our study goes on to show that there is actually a higher incidence of SOS in the non-SCT patient population. ALL was the most common hematological malignancy encountered and had similar prevalence in both groups indicating that treatment regimens used in this cancer carry a high risk of SOS. Drugs like inotuzumab ozogamicin are the possible culprits although this information could not be obtained from our database. AML patients also exhibited high rates of SOS, more so in the SCT setting. Patients with preexisting liver disease and hematological malignancies could also benefit from close monitoring for symptoms of SOS with a high index of suspicion based on our results. Despite rising incidence in non-SCT patients, SCT patients with SOS continue to have a higher mortality possibly indicating the higher toxicity of chemotherapy regimens used in this setting. Thus, our study brings forth some important differences between HSCT and non-HSCT SOS and enables clinicians to identify the associated risk factors.

Toward a Measurable Residual Disease-Based Algorithm for Selection of Allogeneic Hematopoietic Stem Cell Transplant in Acute Myeloid Leukemia

Background: The diagnosis and management of acute myeloid leukemia (AML) have transformed in recent years with an improved understanding of leukemogenesis and improved methods of measurable residual disease (MRD) detection. Current treatment algorithms include consideration of allogeneic hematopoietic stem cell transplant (HCT) for intermediate and adverse-risk AML. MRD negativity is widely accepted as a predictive and prognostic marker for disease-free survival and overall survival. However, the clinical use of MRD status in consolidative HCT planning remains unclear. Methods: Two hundred thirty-three consecutive patients achieving complete remission (CR) as defined in ELN 2022 after receiving therapy at Massey Cancer Center were analyzed. MRD status was determined either by multiparameter flow cytometry, PCR-based sequencing, and/or next-generation sequencing. Patients were analyzed via retrospective chart review to obtain baseline characteristics, molecular and cytogenetic profiles, and survival data. Median overall survival (mOS) was calculated and compared using the Kaplan-Meier method. Continuous variables were compared using one-way ANOVA. Categorical variables were analyzed using Fisher's exact test. Results: In total,109 patients achieved MRD-negative CR and 124 patients achieved an MRD-positive CR. Of the MRD-negative patients, 42 went received HCT (39%). In the MRD-positive cohort, 44 underwent HCT (35%). Among the MRD negative group, those receiving HCT tended to be younger (52.1 y. [range: 24.8-71.7] vs 61. 8 y. (range: 27.1-82.9) p = 0.026) with fewer co-morbidities (Charlson comorbidity index [CCI] score: 3 [range: 2-9] vs 4 (range: 0-14), p = 0.322). We observed a similar trend in those who had MRD positivity at best response or at the time of transplant (age 55 y. [range: 24.5-72.2] vs 62 y. [range: 25.1-88], p = 0.142; CCI 4 [range: 2-7] vs 5 (range 2-11], p = 0.014). In the MRD-negative/no HCT group, 49.3% had ELN favorable-risk disease at initial AML diagnosis, 28.4% had intermediate risk, and 22.4% had adverse risk. In the MRD-negative/HCT group, 31% were favorable risk, 33.3% intermediate risk, and 35.7% were adverse risk. In the MRD-positive/HCT group, 46.3% favorable risk, 23.8% intermediate risk, and 29.5% were adverse risk. There were no significant differences in ELN risk between any group. MRD-positive patients who underwent HCT had a mOS of 25.7 m. vs 20.7 m. for no HCT (HR=0.68 [95% CI, 0.41-1.11], p = 0.125). The median OS was not reached for MRD-negative patients, regardless of receipt of HCT (HR=0.61 [95% CI, 0.30-1.23], p = 0.168). Patients undergoing HCT in MRD-negative CR had improved OS compared to those undergoing HCT with persistent MRD positivity (p = 0.006). Discussion: MRD positivity is a known predictor of relapse and decreased survival despite HCT. However, the use of MRD as a decision point predicting which patients will benefit from transplant a priori needs to be better understood. Our data suggest that MRD negativity has a more significant impact on overall prognosis than HCT status.Likewise, the negative impact of MRD positivity was not significantly abrogated by subsequent HCT. This highlights the need for refinement in HCT selection beyond ELN 2022 intermediate/adverse-risk patients, and new validated algorithms incorporating MRD status are warranted.

Outcomes after Bone Marrow Versus Peripheral Blood Stem Cell Matched Unrelated Donor Hematopoietic Stem Cell Transplantation

Background: Matched unrelated donors (MUD) have become an acceptable alternative donor for patients requiring potentially curative hematopoietic stem cell transplantation (HSCT) and lacking a matched sibling donor. Patients may undergo a bone marrow (BM) or peripheral blood stem cell (PBSC) graft, with previous studies showing similar survival outcomes. However, BM grafts have shown a lower incidence of chronic graft-versus-host disease (GVHD) but a higher relapse rate and slower engraftment. We aimed to compare the outcomes of BM versus PBSC in patients undergoing MUD HSCT. Methods: For this retrospective single-center study, we included all (n=276) adult MUD HSCT recipients at the University of Kansas Medical Center who had at least one year of follow-up (August 2016 to July 2021). We conducted a bivariate analysis using chi-squared and ANOVA tests. The Kaplan-Meier and regression analyses were also performed. Data analyses were conducted using SPSS version 28. Statistical significance was considered at p&amp;lt;0.05. Results: Our study included 276 MUD patients including 110 PBSC (40%) and 166 BM (60%) grafts. The median age was 55 (range 21-77) years, and 158 patients (57%) were males. Eighteen patients (6%) were ethnic minorities, and 89 (32%) patients had a Karnofsky performance status of ≥90%. 118 (43%) patients had a hematopoietic cell transplantation-specific comorbidity index of 3 or higher. Hematologic diseases included acute myeloid leukemia (n=119, 43%), myeloid disorders (n=77, 28%), acute lymphoblastic leukemia (ALL) (n=35, 13%), Lymphoma (n=15, 5%), and others (n=30, 11%). Sixty-two percent of patients were in complete remission at the time of transplantation, and patients not in remission included myelodysplastic syndrome, myelofibrosis, and lymphoma patients. Reduced-intensity conditioning (RIC, n=162, 58%) and myeloablative conditioning (MAC) (n=114, 41%) were used. The median follow-up was 55 (21-73) months. Overall survival (OS) was not reached in either BM or PBSC MUD HSCT group, while a median disease-free survival of 45 and 49 months was noted in PBSC and BM groups respectively (p=0.915). We observed similar rates of relapse (25% vs 27%, p=0.413), one-year overall survival (75% vs 72%, p=0.679), one-year disease-free survival (63% vs 62%, p=1.00), and one-year non-relapsed morality (NRM, 23% vs 21%, p=0.779) after PBSC or BM graft. Bone marrow graft recipients had delayed engraftment of neutrophils (20 days vs 16 days, p&amp;lt;0.001) and platelets (&amp;gt;20 K/uL: 24 days vs 16 days, p&amp;lt;0.001; &amp;gt;50 K/uL: 28 days vs 18 days, p=0.006) compared to PBSC recipients. Bone marrow graft recipients had similar rates of grade II-IV acute GVHD (50% vs 52%, p=0.714) and grade III-IV GVHD (12% vs 11%, p=0.847), but lower rates of 1-year chronic GVHD (39 % vs 55%, p=0.014) compared to PBSC recipients. In the subgroup analysis stratified by conditioning intensity, faster engraftment of neutrophils (median 16 vs 21 days, p&amp;lt;0.001) and platelets (&amp;gt;20 K/uL: 18 days vs 27 days, p&amp;lt;0.001; &amp;gt;50 K/uL: 18 days vs 33 days, p&amp;lt;0.001) was observed with PBSC as compared to BM graft in myeloablative transplant recipients, while there was no statistically significant association with the rates of acute or chronic GVHD, NRM, Relapse, DFS, and OS after a PBSC or BM graft. Among the RIC transplant recipients, faster neutrophil engraftment (mean 17 vs 20 days, p&amp;lt;0.001) and higher 1-year extensive chronic GVHD (52% vs 32%, p=0.015) were observed with PBSC compared to BM graft whereas no statistically significant difference was noted in platelet engraftment, acute GVHD, NRM, Relapse, DFS, and OS after a BM or PBSC graft. Conclusions: Allogeneic matched unrelated donor hematopoietic stem cell transplant recipients had similar rates of overall and disease-free survival, relapse, non-relapse mortality, and acute GVHD after a bone marrow or peripheral blood stem cell graft; however, delayed neutrophil and platelet engraftment with a lower incidence of chronic GVHD was noted after a bone marrow graft compared to peripheral blood stem cell graft.

Thalassemia patients in transfussion dependent period and after hematopoietic stem cell transplantation: how are the psychiatric status and life quality of these patients?

Although hematopoietic stem cell transplantation (HSCT) has been widely used to treat patients with beta-thalassemia major, evidence showing whether this treatment improves mental health, self esteem and health-related quality of life (HRQoL) is limited. We aimed to describe psychiatric problems, HRQoL and self-esteem scores of patients who have thalassemia and compared with patients who underwent HSCT in the current study. A total of 24 patients with thalassemia major and 13 patients who underwent HSCT at least 2 years ago aged between 7-37 years were included. We used The Children’s Depression Inventory, The Spielberger State-Trait Anxiety Inventory, and Pediatric Quality of LifeTM (PedsQL™) for assesment of children and Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), World Health Organization Quality of Life Scale Brief Version (WHOQOL-BREF) for assessment of adults. We also used Piers Harris Self Concept Scale for children and adults. Psychopathologies are common in both groups (50% in Thalassemia group and 69.2% in HSCT group). Popularity scores in Piers Haris scale of patients in HSCT group were significantly higher compared to thalassemia group (p = 0.03). Additionally, HSCT group had higher scores in physical health subscales of HRQoL in both children and parents’(p = 0.02, p = 0.03 respectively). Our findings suggest improved HRQoL and self-esteem in thalassemia patients after HSCT. However, due to the high prevalence of mental disorders in both groups, we would like to emphasize that clinicians should examine not only the physical but also the psychological state of the patients with thalessemia during the their treatment and follow-up period after HSCT.

Comparison of outcomes of Clostridium difficile infection in autologous stem cell transplant recipients compared to allogenic stem cell transplant recipients.

e19064 Background: Hematopoietic stem cell transplant (HSCT) recipients are at a higher risk of clostridium difficile infection (CDI). The incidence of CDI in allogenic SCT recipients has been shown to be about 2-fold compared to autologous SCT recipients in certain studies. These differences can be attributed to myeloablative chemotherapy and increased duration of immunosuppression in allogenic SCT patients. In this study we evaluate the impact of CDI on in-hospital outcomes in these two groups of patients. Methods: We included all patients with a prior diagnosis or a procedure code for HSCT and CDI using ICD-10 codes from National Inpatient Sample 2016-2019. Patients were stratified into two groups based on the presence or absence of autologous stem cell transfusion. Information was collected regarding patient demographics, Charlson comorbidities, resource utilization (LOS and total hospitalization charges), and outcomes. The outcomes included sepsis, shock, acute kidney injury, ICU admission, and in-hospital mortality. The differences in outcomes between the two groups were studied. Results: The incidence of CDI in autologous stem cell transplant recipients was lower compared to the allogenic HSCT group (5.1% vs. 6.1%, p-0.003). 7,605 patients were included in the study. Of them, 2,460 (32.25%) patients had autologous stem cell transplantation, while the remaining had allogenic stem cell transfusion. A higher proportion of patients in the autologous stem cell transplant group were males (60.7% vs. 54.32%), and patients aged 45-64 years (55.7% vs. 46.4%). Patients who received autologous stem cell transplants had a lower incidence of death (1.6% vs. 7.8%, p &lt; 0.001), sepsis (17.28% vs. 28.18%, p- &lt; 0.001), shock (4.7% vs. 12%, p &lt; 0.001), AKI (15% vs. 31.6%, p &lt; 0.001) and ICU admissions (5.7% vs. 10.7%, p- &lt; 0.001). There was no significant difference in the length of stay between the two groups (21.30 days vs 22.97 days). Patients in the autologous stem cell transplant group had lower hospitalization charges ($318,072.3 vs $402,281.5, p &lt; 0.001) than the allogenic group. Conclusions: Like prior studies, our study is compatible with the lower incidence of CDI in autologous SCT recipients. Our study also suggested a lower in-hospital mortality and better outcomes compared to patients with allogeneic stem cell transplants. Resource utilization was also noted to be lower in autologous stem cell transplant patients. Further research should be conducted to explain the differences and to allow physicians to provide timely treatments to prevent worse outcomes.

Clinical features and prognosis of juvenile myelomonocytic leukemia: an analysis of 63 cases

To investigate the clinical features of juvenile myelomonocytic leukemia (JMML) and their association with prognosis. Clinical and prognosis data were collected from the children with JMML who were admitted from January 2008 to December 2016, and the influencing factors for prognosis were analyzed. A total of 63 children with JMML were included, with a median age of onset of 25 months and a male/female ratio of 3.2∶1. JMML genetic testing was performed for 54 children, and PTPN11 mutation was the most common mutation and was observed in 23 children (43%), among whom 19 had PTPN11 mutation alone and 4 had compound PTPN11 mutation, followed by NRAS mutation observed in 14 children (26%), among whom 12 had NRAS mutation alone and 2 had compound NRAS mutation. The 5-year overall survival (OS) rate was only 22%±10% in these children with JMML. Of the 63 children, 13 (21%) underwent hematopoietic stem cell transplantation (HSCT). The HSCT group had a significantly higher 5-year OS rate than the non-HSCT group (46%±14% vs 29%±7%, P<0.05). There was no significant difference in the 5-year OS rate between the children without PTPN11 gene mutation and those with PTPN11 gene mutation (30%±14% vs 27%±10%, P>0.05). The Cox proportional-hazards regression model analysis showed that platelet count <40×109/L at diagnosis was an influencing factor for 5-year OS rate in children with JMML (P<0.05). The PTPN11 gene was the most common mutant gene in JMML. Platelet count at diagnosis is associated with the prognosis in children with JMML. HSCT can improve the prognosis of children with JMML.

High-dose Chemotherapy Impairs Cardiac Autonomic Control of Hospitalized Cancer Patients Undergoing Autologous Hematopoietic Stem Cell Transplantation.

Autologous hematopoietic stem cell transplantation (HSCT) patients have intermediary and late cardiac autonomic dysfunction, which is an independent mortality predictor. However, it is unknown when this HSCT-related autonomic dysfunction begins during hospitalization for HSCT and whether cardiac autonomic control (CAC) is related to cardiotoxicity in these patients. CAC was assessed in 36 autologous-HSCT inpatients (HSCT group) and 23 cancer-free outpatients (CON group) using heart rate variability analysis. The HSCT group was assessed at five time-points from admission to hospital discharge during hospitalization period. The CON group was assessed once. The severity of cardiotoxicity (CTCAE 5.0) and cardiac troponin I were recorded. The CAC was significantly reduced after high-dose chemotherapy (HDC) (reduction of MNN, SDNN, RMSSD, LFms2 and HFnu, and increase of LFnu and LF/HF; P<0.05). At the onset of neutropenia, pNN50 and HFms2 were also reduced (P<0.05) compared to the admission ones. Although both groups were similar regarding CAC at hospital admission, the HSCT patients showed impaired CAC at hospital discharge (P<0.05). The LF/HF was positively associated with cardiac troponin I and RMSSD was inversely associated with the severity of cardiotoxicity (P≤0.05). CAC worsened during hospitalization for autologous-HSCT, mainly after HDC. In addition, it seems associated to early signs of cardiotoxicity in these patients.

1970. SARS-CoV-2 T-cell specific responses in allogeneic hematopoietic stem cell transplant recipients after second and third dose of BNT162b2 mRNA vaccine

Abstract Background Cell-mediated immunity (CMI) after anti-Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 vaccines has been poorly explored in recipients of allogeneic hematopoietic stem-cell transplantation (HSCT), especially with regard to the 3rd dose (booster). Aim of the study was to assess the specific T-cell responses before and after the 3rd dose of BNT162b2 mRNA vaccine in a cohort of allogeneic HSCT recipients, and compare it with healthy donors (HD). Methods Allogenic HSCT recipients and HD were enrolled before receiving the 3rd dose of BNT162b2 mRNA vaccine. Whole blood for T-cell specific responses was collected before (T1) and 8 weeks after (T2) the booster administration. T-cell responses were assessed with an Interferon (IFN)-γ release assay (IGRA), after overnight stimulation of heparin whole blood with pools of lyophilized peptides, covering the immunodominant sequence of the Spike (S) protein. IFN-γ production was assessed with an enzyme linked immunosorbent assay (ELISA). Statistical analysis was performed with GraphPadPrism. Results 14 HSCT recipients (8M, 6F) and 15 HD (7M, 8F) were enrolled (table 1). Median age was 47 [39-59] and 41 [31-48] years in the HSCT and HD groups, respectively. Time between the vaccine 2nd dose and T1 was significantly longer in HD than HSCT recipients (p&amp;lt; .001), while the time between T1 and T2 did not differ between the two groups. SARS-CoV-2 S specific T-cell responses at T1 were inferior in HSCT recipients compared to HD (median IFN-γ production: 463 vs 231 ng/ml, respectively), although the difference did not reach the statistical significance. No differences were observed at T2. In a before-after analysis, SARS-CoV-2 S specific T-cell responses were significantly increased in HSCT recipients at T2 compared to T1 (median IFN-γ production: 267 vs 881 ng/ml, p=0.02) (Figure 1). At T1, 3 HSCT recipients showed very low or no IFN-γ production, while at T2 only 1 patient still had undetectable IFN-γ production after S peptide stimulation. Table 1:Clinical characteristics of allo-HSCT recipients and HDHSCT: hematopoietic stem-cell transplantation; IQR: interquartile range; ALL: acute lymphoblastic leukemia; AML: acute myeloid leukemia; MDS: myelodysplastic syndrome; T-ALL: T-cell acute lymphoblastic leukemia; AA: aplastic anemia; PMF: primary myelofibrosis; MUD: matched unrelated donor; MMUD: mismatched unrelated donors; NA: not applicable; ns: not significant.Figure 1:IFN-γ Production after Spike peptide stimulation of whole blood from allogenic HSCT recipients and HD.Comparison of IFN-γ production after Spike peptide stimulation of whole blood in allogenic HSCT recipients and HD at T1 (1.A) and T2 (1.B) (before and after BNT162b2 mRNA vaccine 3rd dose, respectively). Before-after representation of IFN-γ production after Spike peptide stimulation in HD and allogenic HSCT recipients (1.C). Conclusion SARS-CoV-2 IGRA represents a useful tool to assess CMI, also in immunocompromised hosts. An additional 3rd BNT162b2 mRNA vaccine booster dose seems to enhance CMI in allogenic HSCT recipients. Further studies are needed to evaluate the duration of SARS-CoV-2 CMI in HSCT recipients compared to HD. Disclosures All Authors: No reported disclosures.

Comparison of Hematopoietic Stem Cell Transplantation and Immunosuppressive Therapy for Patients with Severe Hepatitis-Associated Aplastic Anemia

Background：Hepatitis-associated aplastic anemia (HAAA) is known as a rare variant of acquired aplastic anemia, characterized by a syndrome of bone marrow failure following the development of hepatitis. Immunosuppressive therapy (IST) or hematopoietic stem cell transplantation (HSCT) could provide lifesaving opportunities for severe HAAA patients. However, to date, no cohort has characterized treatment outcome and long-term survival between those patients receiving IST and HSCT. In this study, we aim to retrospectively evaluate the outcome of these two therapies for severe HAAA in China. Methods: Patients consecutively diagnosed as severe HAAA between August 2008 and Jan 2021 were enrolled in this study. The definition of severe HAAA is that severe aplastic anemia developed within three months after documented hepatitis. The enrollments were patients who received HSCT or IST as a first-line treatment. Patients with HSCT were conditioned as described previously with cyclophosphamide (Cy, 120-150 mg/kg, divided doses on days -6 to -2), and rabbit ATG (Thymoglobulin®, Genzyme, Cambridge, MA) (2.5mg/kg once i.v. daily on days -6 to -2) or p-ALG (Anti-lymphocyte Immunoglobulin®, Wuhan Institute of Biological Products Co., Ltd., China) (20mg/kg once i.v. daily on days -6 to -2), Fludarabine 150 mg/m2 i.v.in divided doses on days -6 to -2, with or without Busulfan (Bu, 0.8 mg/kg four times i.v. daily on days -7 and -6). IST consisted of both rabbit ATG (rATG) (3~3.75mg/kg once i.v. daily on 5 days), porcine antilymphocyte globulin (pALG)(20mg/kg once i.v. daily on 5 days), combined with a six-month course of cyclosporine (3mg per kilogram per day orally, with adjustment of the dose to maintain a blood level between 200 and 400 ng per milliliter). Probabilities of overall survival (OS), failure-free survival (FFS), and treatment-related-mortality (TRM) were calculated by Kaplan-Meier method. Results and Discussion: This study retrospectively included 94 consecutive HAAA patients, including 68 patients underwent HSCT and 26 patients receiving IST. The IST and HSCT groups were similar with respect to age and gender ratio. The median follow up were 1752 (±153.62, 95%CI 1450.90~2053.10) days, and 2648 (±321.41, 95%CI 2018.05-3277.96) days among alive patients in the IST and HSCT group, respectively. In HSCT group, all patients achieved neutrophil engraftment. No primary or secondary graft failures (GF) was documented. Compared with patients receiving alternative donor HSCT (n=11), patients in matched sibling donor HSCT (MSD-HSCT) group (n=15) had a significant lower cumulative incidence of acute graft versus host disease (aGVHD) (20±10.33% vs 56.4±15.47%, p=0.048), and lower incidence of cytomegalovirus (CMV) reactivation group (72.73% vs 13.33%, p=0.004). No clinical significance of chronic graft versus host disease (cGVHD) incidence group (43.4±18.85% vs 50±35.4%, p=0.78) and bacterial/fungus infection (26.67% vs 36.36%, p=0.683) was found between MSD-HSCT group and alternative donor-HSCT. Attributable causes of death were pneumonias and severe infection in patients receiving HSCT. In IST group, the hematology response rate to treatment evaluated at 3m, 6m and 12m was 27.68%, 52.94%, and 60.23%, respectively. There were thirteen patients were non-evaluable, including six patients transferred to perform HSCT, two patients were diagnosed MDS/AML transformation and one patient relapsed. The 5-year overall survival (OS) and failure-free survival (FFS) rate was 85.5±4.44% (95% CI, 0.772, 0.946) and 69.6± 5.35% (95% CI, 0.599,0.809) of all enrolled HAAA patients, respectively (Figure 1). For patients receiving different therapy, the 5-year OS rates were 92.86 ± 6.88% in MSD-HSCT group, 72.7± 13.43% in alternative donor-HSCT, and 84.1 ± 7.28% in the IST group (P = 0.56). Otherwise, the 5-year estimated FFS rate was 56.0± 11.51% in the IST group, compared with 92.86 ± 6.88% in the MSD-HSCT group and 72.7± 13.43% in alternative donor-HSCT group (P = 0.10). The cumulative incidence of treatment-related-mortality (TRM) of MSD-HSCT, alternative-HSCT and IST was 7.1±6.9% (95% CI, 80.30-100), 27.3±13.4% (95% CI, 50.60-100), 14±5.54% % (95% CI, 7.58-97.6) (p=0.22), respectively. Even there was no difference between the HSCT and IST groups in OS, MSD-HSCT group still showed superior FFS. Patients receiving alternative donor HSCT, and IST showed comparable OS and FFS. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Comparison of ATG-Based Immunosuppressive Treatment and Allogeneic Hematopoietic Stem Cell Transplantation for Patients with Transfusion-Dependent Non-Severe Aplastic Anemia: A Single Center, Retrospective Analysis

Transfusion-dependent non-severe aplastic anemia (TD-NSAA) refers to aplastic anemia (AA) that is dependent on blood transfusion but does not fulfilling the criteria for severe AA (SAA). It has been clear that allogeneic hematopoietic stem cell transplantation (HSCT) and anti-thymocyte globulin (ATG)-based immunosuppressive therapy (IST) is the front line for the treatment of SAA, but there is no consensus on the treatment timing and strategy for TD-NSAA. The natural history observation reported that the progress-free survival (PFS) of TD-NSAA at 60 months after diagnosis is around 62%, but decreased significantly to 22% at 120 months. In China, the practical guideline recommends cyclosporine-based IST with or without hematopoietic stimulating regimes (such as androgens) as initial treatment, and further treated as SAA if no response was observed after 6 months management. As reported, the hematopoietic response of ATG-based IST was much better than CsA-based IST (75% Vs. 55.8%, 6-month) for TD-NSAA, however, the relapse and clonal expansion are still the unavoidable events. For HSCT, the long-term PFS is much better than IST for SAA, but the complications (including graft versus host disease, various infection, etc.), transplantation related mortality, as well as donor availability still limited its application. At present, there is limited data compared the efficiency of HSCT and IST for TD-NSAA. With the development of haplo-identical transplantation in China, most TD-NSAA own a donor, and we also performed HSCT for those young patients after informed consent. Herein, we respectively compared the efficiency of ATG-based IST and HSCT for TD-NSAA, and also analyzed the risk factors that contribute to the overall survival (OS) as well as event free survival (EFS). During Jul 2011 to Dec 2019, 97 TD-NSAA patients were diagnosed in our cohort, among them, 5 only received supportive treatment, 30 received CsA-based IST with or without androgen, and the other 62 patients received HSCT or ATG-based IST therapy. We further analyzed the efficiency and prognosis of 55 patients aged 16-60 years old who received HSCT or ATG-based IST therapy. Among them, 27 (49.09%) patients received ATG-based IST, and the others performed HSCT (including 14 from sibling donor, 7 from haplo-identical donor and 7 from unrelated donor) (the baseline information showed in Table1). Results showed that the 12-month overall response rate (ORR) of ATG-based IST and HSCT were 48.1% (with 18.52% CR) and 78.57% (with 60.71% CR), respectively (P=0.04, Fig A). The median time of achieving transfusion-free was 94(35-205) and 24(11-139) days, respectively in ATG-based IST and HSCT group (P<0.001, Fig B). The 5-year OS and EFS rates were 54.9±13.3% and 34.5±12.1% in ATG-based IST group respectively, and 70.0±9.0% and 62.6±9.6% in HSCT group, while no statistically differences was observed (Fig C and D). To explore the possible influencing factors of 5-year OS and EFS, we performed COX regression analysis based on age, disease duration, baseline absolute neutrophil count (ANC), hemoglobin (HB), platelet count (PLT), serum ferritin (SF), lymphocyte percentage, and CD4/CD8 ratio. Univariate analysis showed that disease duration, baseline HB, SF, and ANC may affect OS and EFS of patients in ATG-based IST group (Table 2), and multivariate analysis showed that SF≧1000ng/ml was an independent risk factor for OS in ATG-based IST group. While in the HSCT group, patients with disease duration≧20 months had a higher risk of events (Table 3). The subgroup analysis showed that in HSCT group, patients with disease duration of 6 to 20 months had a lower risk of events (HR=0.196, 95%CI: 0.046-0.832); the HR of the group <6 months and ≥20 months were not statistically significant (Fig E). TD-NSAA patients with disease duration between 6 months and 20 months had a higher EFS rate in HSCT group than that in ATG-based IST group (Fig F). The subgroup analysis of mortality was not statistically significant (Fig G). To conclusion, TD-NSAA patients should be actively treated, patients with shorter disease duration and no iron overload may achieve a better response. The 12-month ORR in the HSCT group was higher than that in the IST group, but there was no significant difference in OS rate and EFS rate, even there is a great difference tendency. For TD-NSAA patients with a disease duration between 6 to 20 months, HSCT has a higher EFS rate than IST, which may be a better choice. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Clinical Feature and Effect of Demethylation Therapy in Pediatric Patients with Acute Myeloid Leukemia with Myelodysplasia-Related Changes

Objective:To better understanding of the clinical and biological features of childhood AML-MRC, in this study we retrospectively investigated 70 children with AML-MRC admitted to our hospital and compared with AML-NOS. We also analyzed the effect of demethylation drugs in introduction therapy among these patients. Study design: This retrospective cohort study was conducted at the Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College (IHCAMS). Newly diagnosed AML patients at our hospital between January 2009 and December 2021 with complete data regarding baseline characteristics and treatment outcomes were reevaluated as having AML-NOS or AML-MRC according to the 2016 WHO classification of myeloid neoplasms and acute leukemia, strictly excluding cases of therapy-related myeloid neoplasms and AML with recurrent genetic abnormalities. Patients with acute megakaryocytic leukemia were also excluded. Clinical and laboratory data were searched in electronic medical records. Follow-up information was obtained from electronic records or by contacting family members and was initialized from the day of diagnosis to May 31, 2022, or the day of death. Results: Among the 779 newly diagnosed AML patients in our center, 70 patients met the diagnostic criteria of AML-MRC and 73 patients were AML-NOS. Patients with AML-MRC had lower white blood cell count (9.1 (IQR 3.0~30.0) ×109/L vs.17.6 (IQR 5.9~86.8) ×109/L, p=0.002), lower hemoglobin level (74.5 (IQR 63.5~ 86.0) g/L vs. 80.0 (71.0, 94.0) g/L, p=0.025) and lower bone marrow proliferation level (p=0.001) compared with patients with AML-NOS. More FLT3-ITD positive patients were found in AML-NOS patients than AML-MRC patients (33.8% vs. 7.1%, p<0.001). Among the 70 AML-MRC patients, 41(58.6%) were diagnosed by myelodysplasia-related cytogenetics, 10(14.2%) from MDS history, and 19 (27.1%) from a multilineage dysplasia. Monosomy 7 or deletion 7q(-7/7q-) is the most frequent cytogenetic abnormality (21.6%) followed by complex karyotype (18.8%) in AML-MRC patients. Totally 56 AML-MRC patients and 71 AML-NOS patients accepted chemotherapy in out center. Induction treatment for 69 AML-NOS patients were idarubicin/ cytarabine/ etoposide (IAE) or mitoxantrone/cytarabine/ etoposide (MAE) therapy. For AML-MRC patients, demethylation drugs alone or demethylation drugs combined above regime were also used (15 case) besides IAE/MEA therapy (35 case). Six AML-MRC patients and 2 AML-NOS patients accepted homoharringtonine/cytarabine/ granulocyte colony-stimulating factor (HAG) and 3 patients received hematopoietic stem cell transplantation (HSCT) without induction chemotherapy. Overall complete remission (CR) rate of 1 course were 51.0% in AML-MRC and 68.2% in AML-NOS patients. In IAE/MAE group, higher CR rate were seen in AML-NOS patients (70.3%) than AML-MRC patients (48.4%) p= 0.06). AML-MRC patients treated with demethylation drugs seemed to have higher CR rate than introduced by IAE/MAE (64.2 % vs. 48.3%, p= 0.39). HSCT in CR1 were conducted in 29 AML-MRC patients and 19 AML-NOS patients. Median follow-up periods were 2.17 in AML-MRC group and 2.43 years in AML-NOS. Three-year overall survival (OS) and event-free survival (EFS) were 54.4% (95%CI 42.4%~69.8%) and 75.7% (95%CI 62.8%~91.1%) for AML-MRC, 42.3% (95%CI 30.2%~59.2%) and 45.8% (95%CI 32.8%~63.9%) for AML-NOS patients. Cox analysis revealed that HSCT were associated with higher OS (HR 0.21,95%CI 0.1~0.41, p< 0.001). In AML-MRC patients, 3-year OS in HSCT group were significantly higher than that in non-HSCT group [83.4% (95%CI,69.6%~99.8%) vs. 28.0% (95%CI,14.6%~53.9%), p<0.001]. AML-MRC patients with myelodysplasia-related cytogenetics exhibited lower 3-year OS (41.9% ,95%CI,27.5%~63.8%) compared with MDS history group (64.8% (95%CI,39.3%~100.0%) and multilineage dysplasia (77.1% (95%CI,57.3%~100.0%). complex karyotype (41.9% ,95%CI,27.5%~63.8%) and -7(7q-) (40.0% ,95%CI,21.5%~74.3%) AML-MRC patients had lower 3-year OS than normal karyotype (42.3%, 95%CI,21.8%~82.0%) and the other abnormal karyotype (63.5% ,95%CI,37.3%~100.0%) but without statistical difference. Conclusions: Childhood AML-MRC exhibited a comparable adverse outcome with AML-NOS which can be significantly improved by HSCT therapy. Demethylation may help improve the CR rate of AML-MRC. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Hypofibrinolysis in Pediatric Patients with Veno-Occlusive Disease in Hematopoietic Stem Cell Transplantation

Background Veno-occlusive disease (VOD) is a serious complication of hematopoietic stem cell transplantation (HSCT) with a high incidence in pediatric patients (11-27%). In clinical practice, VOD is diagnosed with criteria including weight gain, ascites, hepatomegaly, hyperbilirubinemia, and refractory thrombocytopenia. To date, there are no established markers for an earlier diagnosis of VOD. The aspect of assessing hypofibrinolysis, which plays a role in VOD pathogenesis, has not been elucidated. This study aimed to detect signs of hypofibrinolysis in HSCT and VOD patients using thrombelastography parameters and to discover correlations between alterations of these parameters and established symptoms of VOD. Patients and Methods Patients admitted for HSCT to the pediatric HSCT ward at the University Children's Hospital Tübingen, Germany, between May 2020 and November 2021 were prospectively enrolled (study group). Patients who underwent minor surgical procedures or follow-up blood tests years after recovering from oncological diseases and who were otherwise healthy, were recruited as a control group. Blood samples for thrombelastography (EX and TPA test, including the coagulation time (CT), clot formation time (CFT), clot amplitude after 5 minutes (A05), maximum clot firmness (MCF), maximum lysis (ML), α-angle, and lysis time (LT)) were taken once to twice weekly in addition to daily routine blood tests in patients undergoing HSCT. Routine testing included blood counts, coagulation parameters, d-dimers, and bilirubin. VOD symptoms were monitored daily and body weight was measured twice a day. Ultrasound screenings for ascites, progredient hepatomegaly, and portal venous flow velocity were performed in case of suspected VOD. All patients received intravenous anticoagulation with 100 IU/kg and day of unfractionated heparin. Of the control group patients, 6 ml blood was collected once per patient for routine coagulation testing and thrombelastography. Results A total of 51 patients with a median age of 7.8 years were recruited in the study group. Of these patients, five (9.8%) developed VOD and received defibrotide treatment. The VOD was graded moderate (n=2; 4%), severe (n=1; 2%) or very severe (n=2; 4%). Defibrotide treatment was initiated for 4 weeks or until the resolution of symptoms in standard dosing (25 milligrams per kilogram per day (mg/kg/d)) in four doses over 2 hours). The control group consisted of 55 patients with a median age of 6.7 years. A significant difference in thrombelastographic measurements was observed when comparing the VOD to the HSCT group. The lysis time after activation of fibrinolysis in the TPA test was prolonged in the VOD group at 3 weeks after HSCT (d+14 to +21: VOD: 330±67 seconds, HSCT: 246±53 seconds, p=0.0106). Additionally, a significant difference between the VOD and control groups was observed in days +14 to +21 (control: LT 234±50 seconds, p=0.0299). For the time points of day 0 to +6 and day +7 and +13 after HSCT lysis time was also prolonged in VOD patients, but without statistical significance (LT: d0 to +6: VOD: 304±57 seconds; HSCT: 251±67 seconds, p=0.06; d+7 to +13: VOD: 278±34 seconds; HSCT: 255±70 seconds, p=0.12). It was observed that LT correlated positively with weight gain (>5%), progredient hepatomegaly, right upper quadrant pain and reduced portal venous flow velocity (d0 to d+6: weight gain: r=0.31, p=0.0351; pain: r=0.44, p=0.0018; hepatomegaly: r=0.37, p=0.0108; d+7 to +13: pain: r=0.35, p=0.0143; hepatomegaly: r=0.39, p=0.0058; d+14 to d+21: weight gain: r=0.42, p=0.0035; pain: r=0.37, p=0.0103; hepatomegaly: r=0.44, p=0.0020; reduced portal venous flow velocity: r=0.35, p= 0.0167). Conclusions The results suggest that HSCT patients and patients diagnosed with VOD show signs of hypofibrinolysis. Fibrinolysis can be assessed in a rapid and accessible way via thrombelastography. Therefore, thrombelastography might be a useful tool to facilitate early diagnosis of VOD and to identify high-risk patients. Larger studies are needed to determine specific cut-off-values. Stefanie Hammer and Michaela Döring contributed equally to this work.

Estimating the Incidence-Based Cost of Illness Due to Hematopoietic Stem Cell Transplantation Using One-Year Insurance Claim Data in Korea.

Long-term follow-up data are required for incidence-based cost-of-illness (COI) studies, and it is difficult to carry out such assessments. To overcome this limitation, we estimated the acute and maintenance-state costs of hematopoietic stem cell transplantation (HSCT) using 1-year claim data. Using Korean National Health Insurance (NHI) data from 2016, 2017, and 2018, we identified patients receiving HSCT based on the procedure code "X5*" (i.e., HSCT). The post-HSCT group was defined as patients without the "X5*" code, but with the code "Z948 (other transplanted conditions)" and indications of HSCT (referring to those who had received HSCT). Mean annual medical use and costs were computed using the monthly values available for each patient. The mean number of hospitalizations/year, outpatient visits per year, hospitalization days/year, and length of stay (LOS)/hospitalization were 8.14, 35.80, 97.16, and 14.72, respectively, for allogeneic HSCT patients (n = 56); 8.08, 33.58, 73.04, and 10.63, respectively, for autologous HSCT patients (n = 89); 2.93, 29.40, 50.95, and 20.84, respectively, for post-allogeneic HSCT patients (n = 40); and 1.72, 16.38, 30.11, and 19.29, respectively, for post-autologous HSCT patients (n = 252). The estimated annual NHI-covered medical costs (US dollars) were $38,833-$40,876 for the allogeneic HSCT group, $1749-$6744 for the post-allogeneic HSCT group, $21,231-$22,863 for the autologous HSCT group, and $3954-$5352 for the post-autologous HSCT group. This study describes an alternative method for conducting incidence-based COI studies using cross-sectional claims data.

Treatment for relapsed acute promyelocytic leukemia: what is the best post-remission treatment?

BackgroundArsenic trioxide (ATO) is the standard treatment for relapsed acute promyelocytic leukemia (APL). However, consensus on post-remission therapies is still lacking.MethodsWe evaluated 52 patients who experienced relapse following initial treatment of APL between 2000 and 2019 at Catholic Hematology Hospital. Among them, 41 patients received reinduction treatment, 30 with ATO-based regimen, whereas 11 with conventional intensive chemotherapy (IC).ResultsThe ATO reinduction group showed a significantly higher second molecular complete remission (mCR2) rate, superior neutrophil and platelet recovery, and a lower infection rate than the IC reinduction group. No significant differences were observed in survival outcomes after post-remission treatment among the ATO-based (N=19), autologous (N=12), and allogeneic (N=6) hematopoietic stem cell transplantation (HSCT) groups. In the ATO-based and autologous HSCT groups, among patients with mCR2 after ATO reinduction, nine and five patients experienced a second relapse, respectively (50.7% vs. 41.7%, P=0.878). Among these patients, seven received salvage allogeneic HSCT; six remained alive. The other seven patients received ATO without HSCT. Five died from disease progression, and two survived and have been in mCR2 since.ConclusionPost-remission treatment outcomes of patients with relapsed APL were not significantly different, regardless of the treatment option, suggesting the feasibility of ATO-based treatment without HSCT in mCR2. Allogeneic HSCT may be an effective salvage treatment modality for patients with a second relapse. Owing to a few cases of relapsed APL, multicenter prospective studies may help elucidate the efficacy of each post-remission treatment.