Haploidentical Family Members Research Articles

Outcomes of blood and marrow transplantation in children less than 2-years of age

Allogeneic hematopoietic cell transplantation (Allo-HCT) is a curative option for children with various malignant and non-malignant diseases. Most reports studied all age groups amongst children. Herein we analyzed our data in children transplanted at or less than 2-years of age. We reviewed medical charts of 618 patients who underwent 666 transplantation at our center between 1993 and 2015. There were 340 boys and 278 girls. Median age was 0.7 years (range 0.04-2). Stem cell source was bone marrow (BM) in 492 (73.9%), unrelated umbilical cord blood (UCB) in 161 (24.2%) followed by peripheral blood stem cell (PBSC) in 13 (2%) patients. Matched siblings were the most common donors (n=356, 53.5%), followed by unrelated (n=161, 24.2%) with haploidentical family member donors in 29 (4.4%) transplants. Disease groups were categorized as benign hematology (Thalassemia, Fanconi, Aplastic anemia etc.), benign neoplasm (Langerhans cell histiocytosis, Hemophagocytic Lymphohistiocytosis etc.), non-neoplasms (metabolic disorders, immunodeficiency disorders etc.) and Leukemia/lymphomas (myeloid and lymphoid malignancies etc.). Cumulative incidence of acute GvHD (I-IV) was 31.5% (n=210) and grade III-IV GvHD was 8.7% (n=58). At median follow-up of 115.1 months, the cumulative probability of overall survival (OS) at 5 years was 70.0%±1.9%. Our mortality rate was 31.2% (n=193). The five-year OS was significantly better in patients transplanted for benign hematological disorders (P=.001). Patients transplanted using BM/PBSC as source of stem cells fared significantly better compared to those in which CB was used (P<.001). Post-transplant graft failure remains the leading cause requiring further transplants in this age group. In conclusion, the cumulative probability of OS at 5 years was about 70.0% for all with an OS of 61% in our haploidentical recipients. Analyzing our institutional data over time has enabled us to develop tentative strategies to minimize transplant related toxicities in very young children who are candidates for allo-HCT.

CT-163 Outcomes of Hematological Malignancy Patients Who Underwent Haploidentical SC Transplant With ATG of 2 Mg/kg Based Conditioning Regimen

Hematopoietic stem cell transplantation from human leukocyte antigen (HLA)-haploidentical family members (Haplo-HSCT) offers a potential cure for patients with hematological malignancies who lack an HLA-matched donor. Haplo-HSCT with post-transplant cyclophosphamide (PTCY) is associated with induced immune tolerance, rapid hematopoietic recovery, lower graft-versus-host disease (GVHD), and lower non-relapse mortality (NRM). We noticed a high incidence of high-grade GVHD, so we added antithymocyte globulin (ATG) to the Haplo-HSCT transplant platform. Here we review the outcomes of patients who received PTCY and ATG 2 mg/kg (ATG-2). We retrospectively reviewed the medical records of all patients who underwent Haplo-HSCT for malignant hematologic disorders, using myeloablation, ATG-2, and PTCY for GVHD prophylaxis. We analyzed the patient's characteristics and outcomes of the transplant. We used the Kaplan-Meier method to estimate survival probabilities. Statistical analysis was performed with EasyMedStat. Fifty-three-patients were reviewed, 26 (49.1%) males and 27 (50.9%) Females. The majority of patients had AML (60%). Other diagnoses included ALL, CML, MDS, APL, and BPDCN. Seventy-one percent of patients received bone marrow harvested cells and 27% received PBSCT and 2% received both BM and PBSCT. The conditioning was myeloablative in the form of Thiotepa/Busulfan/Fludarabine (73.5%) for myeloid malignancies and Fludarabine/TBI 1000 cGy (26.4%) for lymphoid malignancies. The median duration of follow-up was 15 months. At 12 months, the overall survival (OS) was 73.4% (95% CI: 59.3-83.3), and the relapse-free survival (RFS) was 70.3% (95% CI: 55.6-80.9). 33% of patients developed GII to IV acute GVHD and 17% of patients developed extensive chronic GVHD. There were no cases of primary graft failure (GF), but two patients developed secondary GF. One-third of patients developed hemorrhagic cystitis (33.9%) and the majority of patients (90.5%) developed CMV reactivation. Only two patients developed Veno-occlusive disease (VOD). Haplo-HSCT for hematological malignancies with myeloablative conditioning, PTCY and ATG 2 mg/kg is feasible and associated with favorable OS, and RFS. The risk of GVHD, VOD, and GF is comparable to other case series.

Management of Invasive Fungal Infections in Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplantation: The Turin Experience.

BackgroundAllogeneic hematopoietic stem cell transplant (allo-HSCT) recipients are exposed to an increased risk of invasive fungal infections (IFIs) due to neutropenia, immunosuppressive treatments, graft-versus-host disease (GvHD) and incomplete immune reconstitution. Although clinical benefit from antifungal prophylaxis has been demonstrated, IFIs remain a leading cause of morbidity and mortality in these patients. In the last decades, attention has also been focused on potential risk factors for IFI to tailor an antifungal prevention strategy based on risk stratification.Aim of the StudyThis retrospective single-center study aimed to assess the epidemiology and the prognostic factors of IFI in a large cohort of allo-HSCT patients.MethodsBetween January 2004 and December 2020, 563 patients with hematological malignancies received an allo-HSCT at the Stem Cell Transplant Unit in Turin: 191 patients (34%) received grafts from a matched sibling donor, 284 (50.5%) from a matched unrelated donor, and 87 (15.5%) from an haploidentical family member. The graft source was peripheral blood in 81.5% of the patients. Our policy for antifungal prophylaxis included fluconazole in matched related and unrelated donors, while micafungin was administered in patients receiving haploidentical transplant. According to this practice, fluconazole was administered in 441 patients (79.6%) and micafungin in 62 (11.2%), while only 9 patients received mold-active prophylaxis. Galactomannan testing was routinely performed twice a week; patients with persisting fever unresponsive to broad spectrum antibiotics were evaluated with lung high-resolution computed tomography (HRCT) scan. In case of imaging suggestive of IFI, bronchoalveolar lavage (BAL) was performed whenever feasible.Statistical AnalysisOnly probable/proven IFI (PP-IFI) occurring during the first 12 months after transplant have been evaluated. IFIs were classified as probable or proven according to the new revised European Organization for Research and Treatment of Cancer (EORTC)/Mycoses Study Group (MSG) consensus criteria. Multivariate competing risk regression, binary logistic, and proportional hazard models were performed to identify risk factors for PP-IFI.ResultsA total of 58 PP-IFIs (n = 47 probable; n = 11 proven) occurred in our patients resulting in a cumulative incidence of 4.1%, 8.1%, and 9.6% at 30, 180, and 365 days, respectively. Molds were the predominant agents (n = 50 Aspergillus; n = 1 Mucor), followed by invasive candidemia (n = 5 non-albicans Candida; n = 1 Candida albicans; n = 1 Trichosporon). Lung was the most frequent site involved in patients with mold infections (47/51, 92.2%). Median time from HSCT to IFI was 98.44 days (0–365 days). Only 34.5% of patients with IFI were neutropenic at the time of infection. The presence of IFI had a significant impact on overall survival at 1 year (IFI, 32.8% vs. non-IFI, 54.6%; p < 0.001). IFI-related mortality rate was 20.7% in the overall population, 17% in patients with probable IFI, and 36% in patients with proven IFI. Multivariate competing risk regression revealed that donor type was the factor significantly associated to the risk of IFI [subdistribution hazard ratio (SDHR), 1.91, IC 1.13–3.20; p = 0.015]. BAL was informative in a consistent number of cases (36/57, 63.2%) leading to the identification of fungal (21), bacterial (4), viral (3), and polymicrobial (8) infections. Overall, 79 patients (14%) received a diagnostic-driven treatment, and 63 patients (11.2%) received a fever-driven treatment. Liposomal amphoteric B was the drug used in the majority of patients receiving diagnostic-driven therapy (30/79, 38%), while caspofungin was administered more frequently in patients who received a fever-driven strategy (27/63, 42.9%).ConclusionAccording to our experience, a non-mold active prophylaxis in patients undergoing allo-HSCT is feasible when combined with an intensive diagnostic work-up including CT scan and BAL. BAL performed at the onset of the disease may provide informative results in most patients. A diagnostic-driven treatment strategy may contribute to limit the use of costly antifungal therapies.

Interleukin-7 Receptor Gene Heterozygous Mutations in Recipients Significantly Increase Acute Graft-Versus-Host Disease after Allogeneic Hematopoietic Stem Cell Transplantation

Acute graft-versus-host disease (aGVHD) is one of major complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Genetic polymorphisms of interleukin-7 receptor (IL-7R) have an impact on transplant-related mortality (Z Shamim et al. BMT 2006). Our previous studies indicated that hematological and immunological hereditary predisposition genes have potential influence on major complications of allo-HSCT in patients with hematological malignancies (unpublished data). In present study, the influence of hematological and immunological hereditary predisposition genes on aGVHD after allo-HSCT in the patients with hematological malignancies was investigated. Between February 2018 and August 2019, 92 patients with hematological malignancies who underwent allo-HSCT in Beijing Boren Hospital were enrolled. The median age was 17 (1 to 45) years old. The diagnoses included acute myeloid leukemia (37, 40.2%), acute lymphoblastic leukemia (36, 39.1%), non-Hodgkin's lymphoma (13, 14.1%), and myelodysplastic syndrome (6, 6.5%). The disease status before transplant was complete remission in 54 (58.7%), non-remission in 23 (25%), and relapse in 15 (16.3%). Before transplants, blood samples were collected from the patients, their parents and potential related donors to detect hematological and immunological hereditary predisposition genes with whole exon sequencing and validation by sanger sequencing. The donors were from identical siblings (4, 4.3%) or matched unrelated volunteers (8, 8.7%) or haploidentical family members (80, 86.9%). Myeloablative conditioning regimens with either total body irradiation/fludarabine-based or busulfan/fludarabine-based were applied. Anti-thymocyte globulin was used in haploidentical and unrelated transplants. GVHD prophylaxis was with cyclosporine, short-term methotrexate and mycophenolate mofetil. Methylprednisolong 1-2mg/kg daily was used for aGVHD treatment and basiliximab was administrated in severe aGVHD. Forty-eight patients (52.2%) developed aGVHD as aGVHD group and 44 patients (47.8%) have no aGVHD as non-aGVHD group. IL7R gene heterozygous mutations in recipients significantly increased overall aGVHD and also severe aGVHD after allo-HSCT. IL7R gene heterozygous mutations were found in 7/48 patients in aGVHD group, but 0/44 in non-GVHD group (P = 0.041). The incidence of grade III-IV aGVHD in patients with IL7R gene heterozygous mutations was significantly higher than that without IL7R gene heterozygous mutations. (5/7 vs. 7/41, P=0.007). Among the patients with IL7R gene heterozygous mutations in aGVHD group, 5/7 patients (71.4%) had grade III-IV aGVHD. Three of them with grade III aGVHD had the same heterozygous mutation site: c.c1241t; p.t414m and rest 2 patients with grade IV aGVHD had the same heterozygous mutation site: c.g314a; p. S105n. Our preliminary results have shown that IL7R gene heterozygous mutations in recipients have significantly increased the risk of overall aGVHD and severe aGVHD after allo-HSCT in the patients with hematological malignancies. Larger sample size is needed to address this issue. Disclosures No relevant conflicts of interest to declare.

Influence of Inherited and Acquired Hematological and Immunological Gene Variants on the Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Hematological Malignancies

Chromosome abnormalities and gene variants are important factors in prognosis of the patients with hematological malignancies. Our previous study showed that some germline gene mutations-related to hematological and immunological disorders may have negative impact on the complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT). In current study, the influence of both hematological and immunological hereditary predisposition gene variants and tumor gene variants on the outcomes of allo-HSCT in patients with hematological malignancies was studied. Between January 2018 and June 2020, 164 patients with hematological malignancies who underwent allo-HSCT in our hospital were analyzed. The median age was 14 (1 to 67) years old. The diagnosis included acute myeloid leukemia (n=68, 41.5%), acute lymphoblastic leukemia (n=67, 40.8%) and non-Hodgkin's lymphoma (n=29, 17.7%). The disease status before transplant was CR1 in 49 cases (29.9%), CR2 in 63 cases (38.4%), PR in 22 cases (13.4%), and NR in 30 cases (18.3%). Donors were from haploidentical family members (n=125, 76.2%) or identical siblings (n=18, 11.0%) or unrelated volunteers (n=21, 12.8%). Myeloablative conditioning regimens with either total body irradiation/fludarabine-based or busulfan/fludarabine-based were applied. Anti-thymocyte globulin was used in haploidentical and unrelated transplants. Graft-versus-host disease (GVHD) prophylaxis was with cyclosporine, short-term methotrexate and mycophenolate mofetil. Before transplant, blood samples from patients, their parents and potential related donors were collected to analyze for more than 700 kinds of hematological and immunological hereditary predisposition genes with whole exon sequencing and validation by sanger sequencing. The average sequencing depth was 150×. At diagnosis or relapse, bone marrow samples from patients were obtained to detect for 339 kinds of tumor genes by Illumina sequencing. The average sequencing depth was more than 3000×. With the median follow-up 12.6 (11.2 to 17.0) months, 105 patients (64.0%) achieved durable remission after allo-HSCT. Forty-seven patients (28.7%) relapsed. Twelve patients (7.3%) died. Total 191 immunodeficiency-related hereditary predisposition gene variants were identified in this cohort (average 3.5 gene variants per patient; range, 0-10). Twenty-six of them were recurrent more than 6 times that including TYK2, IFIH1, CFTR, LRBA, IL7R, POLE, RNF31, NLRP12, TTC7A, ATM, CARD14, CHD7, NOD2, TNFRSF13B, BLB,CFB, EPG5, C8A, C8B, CFH, IRF, MSH6, NCF2, NFAT5, PMS2 and ST1M1.IFIH1and IL10RB gene variants were poor factors for relapse post-transplant (P=0.006, P=0.007). The functions of these genes involve in combined immunodeficiency, autoinflammatory disease, complement deficiency, immune deficiency, T-cell dysfunction and antibody deficiency. Total 153 tumor gene variants were identified in this patient series (average 1.93 gene variants per patient; range, 0-16). Seventeen of them were recurrent more than 4 times that including TP53, TPN11, KIT, FLT3, NRAS, NUDT15, STK11, CREBBP, NPM1, DNAH9, DNMT3A, IDH2, HEK2, KRAS, KMT2C, NOTCH1 and NR3C1. TP53, KRAS and NUDT15 gene variants were poor factors for relapse after allo-HSCT (P=0.000025, P=0.0082, P=0.000018). Hemophagocytic lymphohistiocytosis (HLH)-related genes variants were found in 9 patients (5.5%). Frequent HLH-related gene variants were in CD27, PRF1, STX11, and UNC13D. Fanconi anemia (FA)-related gene variants were seen in 11 patients (6.7%). Common FA-related gene variants were in BRCA1, BRCA2, BRIP1, FANCA, FANCC, FANCF, FANCM and FANCG. Significantly higher incidences of acute GVHD (aGVHD) and/or infections were noted in the patients with HLH and/or FA-related gene variants compared with those without HLH and FA-related gene variants (p=0.019). Our results have shown that both inherited and acquired hematological and immunological-related gene variant profiles in the patients with hematological malignancies and some recurrent gene variants (IFIH1 and IL10RB; TP53, KRAS and NUDT15) have negative impact on the outcomes of allo-HSCT including leukemia-free survival, aGVHD and infections. Keywords: allogeneic hematopoietic stem cell transplant, gene expression, relapse, hematological malignancy Disclosures No relevant conflicts of interest to declare.

A Prospective Haploidentical Peripheral Blood Stem Cell Transplant Study Using a Pre-Defined Conditioning Regimen Intensity Based on Age and the Hematopoietic Cell Transplantation Comorbidity Index- Anzhit 1: Encouraging Preliminary Survival Outcomes at One Year Follow up

Background HLA-matched sibling and unrelated donors are not always available for patients that are in need of an allogeneic haematopoietic stem cell transplant. Partially HLA-mismatched related (haploidentical) donors can be identified for the vast majority of patients but these transplants were historically complicated by excessive graft versus host disease (GVHD), nonrelapse mortality (NRM), and poor overall survival (OS). Haploidentical haematopoietic stem cell transplantation (Haplo HSCT) has become increasingly common over the last ten years, predominately due to the successful use of post-transplant cyclophosphamide (PTCy) in mitigating graft versus host disease (GVHD). Most studies using PTCy have been retrospective with various conditioning regimens and stem cell sources making interpretation of results difficult. ANZHIT-1 is a prospective Australian multi-centre phase II study of Haplo HSCT with defined conditioning and GVHD prophylaxis regimens. Methods: This is an ethics approved Phase II study (ACTRN: 12617000151336) conducted between 2015-2020 at six Australian allogeneic HSCT centres. All patients received peripheral blood Haplo HSCT from haploidentical family members. The reduced intensity regimen (RIC) was fludarabine, cyclophosphamide and 200cGy TBI and the myeloablative regimen (MAC) was fludarabine with IV busulfan 3.2mg/kg x 4. PTCy 50mg/kg D+3, D+4 was used with MMF (to D35) and a calcineurin inhibitor (CNI) as GVHD prophylaxis. CNIs were weaned and ceased by D+120 in patients who did not have evidence of GVHD. Choice of conditioning regimen was based on age and hematopoietic cell transplantation comorbidity index (HCT-CI) scores. Patients who had an HCTCI &amp;gt;3 or age &amp;gt;50yrs received RIC. Data collection was through the Australian Bone Marrow Transplant Recipient Registry. Survival was analysed using the Kaplan-Meier method. Results: Seventy eight patients were included in the study with a median follow up of 402.5 days (28-1259). There was a male predominance (66%). The median age was 53 years (range 18-69) and the median HCT-CI score was 1 (range 0-5). Thirty nine patients had acute myeloid leukaemia, 12 acute lymphoblastic Leukaemia, 14 Non Hodgkin lymphoma or Hodgkin lymphoma, 4 myelodysplastic syndrome and 9 other diagnoses. The majority received RIC (59%). Median neutrophil and platelet engraftment times were 18 days (range: 12-92) and 28 days (range: 13-262) respectively. Acute GVHD grade III-IV occurred in 14.1% of patients whilst chronic GVHD occurred in 20.5%. Moderate to severe cGVHD according to NIH consensus criteria occurred in 10.3% of patients. Overall survival probability at one year was 74.1% (95% CI: 52.9-86.8) for MAC recipients and 77.8% (95% CI: 61.6-87.8) for RIC recipients (Figure 1). Non relapse mortality (NRM) at D100 and 1 year were 2.2% and 8.7% respectively in the RIC group compared to 6.3% and 18.8% respectively in the MAC group. Causes of NRM included infection (n=5), GVHD (n=3) and VOD, respiratory failure and multi-organ failure in one patient each. Haemorrhagic cystitis and poor graft function were relatively common post-transplant morbidities but rarely contributed to NRM. Despite the use of peripheral blood stem cells and early weaning of CNIs, only 3/11 NRM deaths were due to GVHD. Relapse was the most common cause of death in the RIC group with 17.4% of patients relapsing at a median of 114 days (range 36-564) compared to only 6.3% at a median of 90.5 days (range 64-154) in the MAC group. Conclusion: This prospective Haplo HSCT trial utilising PTCY demonstrates encouraging overall survival rates. The RIC regimen had a promising toxicity profile but early relapse remains a concern despite early weaning of CNIs. In contrast, the MAC regimen is associated with a low relapse rate but NRM at one year remains significant. Further refinement of the conditioning and GVHD prophylaxis regimens will be incorporated in the follow-on study, ANZHIT-2, which will begin accrual in late 2020. Disclosures Bajel: Pfizer: Honoraria; Amgen: Honoraria, Speakers Bureau; Novartis: Honoraria; Astellas: Honoraria; Abbvie: Honoraria. Greenwood:Servier: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Hamad:Novartis: Honoraria; Abbvie: Honoraria.

CD34+ selected peripheral blood Stem Cell Boost (SCB) for Poor Graft Function (PGF) or mixed chimerism in pediatric patients, after hematopoietic stem cell transplantation: Results of a retrospective multicenter study.

PGF is historically associated with high morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In this study, we report our multicenter experience on stem cell boost (SCB) for PGF, or incomplete donor engraftment, in 16 pediatric patients. Donors were HLA-matched siblings (n=4), unrelated donors (n=11), or haploidentical family members (n=1). Ten patients had two-lineage cytopenia, 5 had one-lineage cytopenia, and 1 had poor immunological reconstitution together with a low percentage of donor cell engraftment. A median of 6.6x106 selected CD34+/Kg was infused after 194days from allo-HSCT (48-607). In 4 out of 5 patients, one-lineage cytopenia was resolved, while among the 10 patients with two-lineage cytopenia, 4 resolved both cytopenia, 5 resolved one-lineage, and one did not respond. All patients reverted their mixed chimera to full donor chimera. OS was 56%, transplant-related mortality (TRM) 32%, and RI 12%. The main causes of failure were related to infections with 4 out of 7 deaths caused by this. SCB may rescue over 50% of patients with PGF after allo-HSCT. An earlier treatment may reduce the infectious complications and improve survival.

Safety and efficacy of patients with refractory B-lymphoblastic leukemia treated with anti-CD19 CAR-T cell bridging to allogeneic hematopoietic stem cell transplantation

目的探讨抗CD19 CAR-T细胞治疗达深度缓解后序贯异基因造血干细胞移植（allo-HSCT）治疗难治B淋巴细胞白血病的疗效及不良反应。方法回顾性分析2017年11月至2019年3月河南省肿瘤医院收治的10例抗CD19 CAR-T细胞治疗达深度缓解后序贯allo-HSCT难治B淋巴细胞白血病患者的临床资料。结果①10例患者中，男5例，女5例，中位年龄23.5（10～31）岁，其中难治急性B淋巴细胞白血病（B-ALL）9例，慢性淋巴细胞白血病（CLL）1例。10例患者抗CD19 CAR-T细胞治疗后第30天及移植前评估微小残留病（MRD）均为阴性。②亲缘全相合移植2例，亲缘单倍型移植8例，抗CD19 CAR-T细胞治疗获得深度缓解至allo-HSCT中位时间为32.5（20～60）d。③10例患者获得造血重建，中性粒细胞植入中位时间为15（15～21）d，血小板植入中位时间为19（17～30）d。④预处理过程中，10例患者均未出现肝静脉闭塞病及出血性膀胱炎。1例患者出现渗漏综合征，予以限制入量、补充白蛋白及利尿等治疗后好转。移植过程中8例（80％）出现发热，均经抗感染治疗后好转。发生Ⅱ度急性移植物抗宿主病（aGVHD）2例，Ⅲ度aGVHD 1例；至随访截止9例存活患者中8例出现局限性慢性移植物抗宿主病。⑤中位随访262（150～540）d，预期1年总生存率为（90.0±1.0）％，无病生存率为（85.7±1.3）％。结论抗CD19 CAR-T细胞治疗达深度缓解后序贯allo-HSCT可作为难治B淋巴细胞白血病患者的可选治疗方案。

Potential Influence of Hematological or Immunological Hereditary Predisposition Genes on the Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Hematological Malignancies

Introduction: The development of hematological malignancies may be relevant to hereditary predisposition and harmful external environment. Germ line predisposition to myeloid neoplasms has been incorporated in the WHO 2016 classification of myeloid neoplasms. Hereditary predisposition genes may also play a certain role in the complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Objective: In present clinical study, we investigate whether hematological and immunological hereditary predisposition genes have influence on the outcomes of allo-HSCT in patients with hematological malignancies. Methods: Between January 2018 and May 2019, ninety-one patients with hematological malignancies who underwent allo-HSCT with the same protocols in our hospital were enrolled. The median age was 20 (2 to 66) years old. Male to female was 1.53:1. The diagnosis included AML (n=32, 35.2%), ALL (n=47, 51.6%) and NHL (n=12, 13.2%). The disease status before transplants was CR1 in 31 cases (34.1%), CR2 in 45 cases (49.5%), PR in 5 cases (5.5%), and NR in 10 cases (11.0%). Hematological and immunological hereditary predisposition genes of the patients, their parents and potential related donors were prospectively detected before transplant with whole exon sequencing and validation by sanger sequencing. Donors were from haploidentical family members (n=74, 81.3%) or identical siblings (n=6, 6.6%) or unrelated volunteers (n=11, 12.1%). Myeloablative conditioning regimens with either TBI/Fludarabine or Busulfan/Fludarabine were applied. Anti-thymocyte globulin (ATG) was used in haploidentical and unrelated transplants. Graft-versus-host disease (GVHD) prophylaxis was with cyclosporine, short-term methotrexate and mycophenolate mofetil. Prevention of fungal, pneumocystis carinii and herpes virus infections was routinely administrated. Chi-square test was used to analyze whether hereditary predisposition genes were associated with major complications after allo-HSCT. The study used the IBM SPSS Statistics software for analysis. P value &lt;0.05 was considered to be statistically significant. Results: Thirty-one (34.1%) cases carried primary hemophagocytic lymphohistiocysis (HLH) related gene variants and the average number of gene variants was 1.2 (range 1 to 2). More frequent HLH gene variants were in UNC13D, LYST, PRF1, AP3B1 and STX11. Forty-four (48.4%) cases carried Fanconi anemia (FA) related gene variants and the average number of gene variants was 1.27 (range 1 to 3). More frequent FA gene variants were in BRCA2, FANCA, PALB2, FANCD2, BRCA1, FANCL, FANCI and SLX4. Ninety (98.9%) cases carried immunodeficiency related gene variants and the average number of gene variants was 3.25 (range 1 to 10). More frequent immunodeficiency gene variants were in IFIH1, CHD7, TYK2, LRBA, NFAT5, IL7R, NLRP12, POLE, TNFRSF13B, ATM, IGLL1, ORAI1, RNF31, C8A, CBLB, IRF8, LIG1, NCF2, NCF4, STIM1 and TCF3 .The incidence of acute GVHD (aGVHD) in patients carried HLH gene variants was significantly higher than that without HLH gene variants (45.1% vs. 21.6%, p=0.020). Bacterial infections occurred more frequent in patients with FA gene variants than that without FA gene variants (47.7% vs. 21.3%, p = 0.008). There was a trend of higher relapse rate in patients with more than 3 immunodeficiency gene variants than that with less than 3 immunodeficiency gene variants but without statistical significance (23.8% vs. 11.4%, p &gt; 0.05). Conclusions: Our preliminary results have shown that hematological and immunological hereditary predisposition genes have potential influence on major complications of allo-HSCT in patients with hematological malignancies. HLH gene variants increase the risk of aGVHD, and FA gene variants increase bacterial infections after allo-HSCT. The patients with multiple immunodeficiency related gene variants may increase relapse rate post-transplant. A larger cohort and longer follow-up are needed to address this issue. Disclosures No relevant conflicts of interest to declare.

Incorporation of Posttransplant Cyclophosphamide (PCy) As Part of Standard Immunoprophylaxis (IP) for All Allogeneic Transplants: A Retrospective, Single Institution Study

Background: The incorporation of PCy in IP has allowed transplantation of stem cells from haploidentical (HI) family members such that nearly all patients have a potential donor. Thus far, HI stem cell transplantation with PCy appears to yield comparable results to matched unrelated (MUD) and matched sibling donors (MSD) who have been treated with conventional GVHD regimens, but with less chronic GVHD (cGVHD). Particularly in light of the low incidence of cGVHD, which has not been achieved with other IP strategies after T cell-replete products, PCy is being investigated after MUD and MSD transplantation where complications from cGVHD remain the major cause of non-relapse mortality. A recent study from the BMTCTN showed that in patients conditioned with reduced intensity regimens and who received MSD and MUD stem cells, the addition of PCy to standard IP (SIP) was superior to either bortezomib or maravoric in the composite endpoint of graft-versus-host disease-free, relapse-free survival (GRFS). However, this study did not include patients who received ablative conditioning regimens and did not report on the percentage of patients who were disease-free and off immunosuppression (DFOI) at 1 year after transplant. In the present study, we have compared our experience with the addition of PCy for essentially all allogeneic stem cell transplants treated over a 2 year period with the results of patients treated with SIP in the prior two year span. Outcomes of interest included one-year overall survival (OS) and one-year GRFS as well as the percentage of patients DFOI at one year. Methods: With the exception of patients receiving umbilical cord blood transplants, beginning in April 2016, all but two patients who received allogeneic transplants were given mobilized peripheral blood stem cells and then treated with PCy on days +3 and +4 followed by tacrolimus and mycophenolate on day 5. In the absence of GVHD, mycophenolate was stopped at days +35-50 and tacrolimus was tapered beginning after day +100 unless there was low donor chimerism or a suspicion of relapse in which case tacrolimus could be tapered sooner. In order to have at least one-year follow-up, the last patient included in the study was treated before April 2018. During this time period, MSD were prioritized over MUD which in turn were chosen over haploidentical donors. For comparison, we looked at the prior 2 year period (2014-2016) in which patients were treated with SIP (including ATG in patients who received MUD stem cells). Because of a higher percentage of patients with an advanced disease risk index (DRI) in the years 2014-2016, we restricted our analysis in the SIP cohort to those patients with low and intermediate risk disease but included all patients in the more recent period who received PCy. Results: There were 68 patients treated in the PCy group, including 2 patients who received PCy after HI transplants in the years 2014 and 2015. After eliminating patients with high DRI there were 40 patients in the earlier SIP cohort of patients. The resulting patient groups were similar with respect to median age (53) and diagnosis (approximately 80% of patients with AML and ALL). There was a slightly higher percentage of patients in the SIP group with hematopoietic cell transplantation-comorbidity index scores of 3 or more (52.5 vs 48.5). In the PCy group the number of patients with early, intermediate and advanced DRI were 2, 53 and 13, whereas in the (modified) SIP category 2 patients had a low DRI and 38 had intermediate DRI. In the PCy group, HI donors comprised 26.5% of the total compared to 19.1% MSD and 54.4% MUD donors. In the SIP group, MSD and MUD donors accounted for 30% and 70% of the donors. One-year percentages of OS, GRFS and DFOI were 79.4, 47.1 and 44.1 in the PCy group compared to 72, 45 and 35 in the SIP cohort. If the analysis of the PCy group is limited to the 50 patients with MSD and MUD donors (as in the SIP cohort), the one-year OS, GRFS and DFOI are 88, 52 and 52. Conclusions: PCy in combination with SIP resulted in at least comparable results as SIP despite the inclusion of 19% of patients with a high DRI and 26.5% HI donors. The results with the addition of PCy are excellent in patients with MSD and MUD donors with more than half of the patients GRFS and DFOI at one year. Future studies on GVHD prophylaxis should report DFOI as the latter status may be the best platform for posttransplant strategies aimed at eliminating minimal residual disease and for improving QOL. Disclosures No relevant conflicts of interest to declare.

Clinical observation of 12 patients with refractory/relapsed acute myeloid leukemia treated with allogeneic hematopoietic stem cell transplantation containing cladribine regimen

目的评估含克拉屈滨序预处理异基因造血干细胞移植（allo-HSCT）治疗难治/复发急性髓系白血病（AML）的疗效。方法回顾性分析12例接受含克拉屈滨预处理allo-HSCT难治/复发AML患者的临床资料。结果①12例患者中，男9例，女3例，中位年龄36（27~50）岁。亲缘全相合供者移植3例，无关供者移植1例，单倍型移植8例。移植前部分缓解9例，未缓解3例，移植前化疗中位疗程6（2~13）个。②预处理：司莫司汀250 mg·m−2·d−1，−7 d；克拉屈滨5 mg·m−2·d−1，−6 d~−2 d；阿糖胞苷2 g·m−2·d−1，−6 d~−2 d；白消安3.2 mg·m−2·d−1，−6 d~−3 d；兔抗人胸腺细胞免疫球蛋白（ATG）1.5 mg·m−2·d−1（无关供者移植）或2.0~2.5 mg·m−2·d−1（单倍型移植），−4 d~−1 d。③11例患者获得造血重建，1例发生原发植入失败。可评估患者中，中性粒细胞植入时间为15（15~21）d，中位血小板植入时间为19（17~30）d。④预处理过程中，12例患者均未发生肝静脉闭塞病，2例患者发生出血性膀胱炎。移植过程中8例出现发热，均经抗感染治疗后好转。3例患者发生Ⅱ度急性GVHD。至随访截止9例存活患者中8例发生慢性局限型GVHD。⑤中位随访时间为8（4~12）个月，2例患者分别在移植后6、12个月复发。预期1年总生存率为（71.1±1.8）%，无病生存率为（62.2±1.8）%。结论含克拉屈滨预处理allo-HSCT可作为难治/复发AML患者的可选治疗方案。

Influence of donor type, stem cell source and conditioning on outcomes after haploidentical transplant for lymphoma – a LWP‐EBMT study

Haploidentical stem cell transplantation (haploSCT) is becoming a major transplant modality for lymphoma. To assess the effects of donor characteristics, stem cell source and conditioning on outcomes, we identified 474 adults with Hodgkin (HL; 240), peripheral T-cell (PTCL; 88), diffuse large B-cell (77), mantle cell (40) or follicular lymphoma (FL; 29), who received haploSCT with post-transplant cyclophosphamide. Median follow-up of alive patients was 32months. On multivariate analysis, acute graft-versus-host disease (GVHD) grade 2-4 was lower with offspring donors or bone marrow cells, whereas extensive chronic GVHD was higher in partial response at haploSCT or when using sisters, haploidentical donors beyond first degree, or female donors in male patients. Progression-free survival (PFS) was better for FL, HL and PTCL, whereas overall survival (OS) was better for HL and PTCL. Complete remission at haploSCT improved PFS and OS whereas these were negatively affected by cytomegalovirus donor positive/recipient positive status. No other donor characteristics (age, gender, human leucocyte antigen mismatch, ABO incompatibility) affected PFS or OS except use of haploidentical donors beyond first degree, which negatively affected OS. PFS and OS are mostly influenced by disease status and lymphoma subtype, supporting the use of any first degree haploidentical family member as a donor.

Alternative donor transplants for severe aplastic anemia.

Allogeneic hematopoietic stem-cell transplantation remains the only curative treatment for patients with acquired severe aplastic anemia (SAA). When a matched sibling is not available, one can search for a matched unrelated donor or a cord blood unit (CB) in the international registries or, more recently, for an HLA haploidentical (HAPLO) family member. International guidelines call for a course of antithymocyte globulin (ATG) and cyclosporine before a patient with SAA receives a transplant from a donor other than an HLA identical sibling, but whether this is necessary for patients age <20 years is less clear. Here I will examine the rapid increase in HAPLO transplantations for SAA, showing encouraging early results both in children and young adults. Graft-versus-host disease prophylaxis remains of primary importance in patients with SAA, and in vivo T-cell depletion with either ATG or alemtuzumab offers a significant survival advantage. Finally, I will discuss the strong age effect, which is particularly evident at >40 and 50 years of age for reasons not entirely clear and which should be taken into account when designing a treatment strategy for a given patient.

Impact of Donor Chimerism-Guided Immunomodulation after Allogeneic Stem Cell Transplant on the Outcome of Patients with AML and MDS

Impact of Donor Chimerism-Guided Immunomodulation after Allogeneic Stem Cell Transplant on the Outcome of Patients with AML and MDS

Does Mixed Chimerism after Allogeneic Hematopoietic Cell Transplantation in Patients with Fanconi Anemia Impact on Outcome?

Fanconi anemia (FA) cells are characterized by genomic instability which places FA patients (pts) at risk for malignancies; leukemia and oropharyngeal/urogenital cancers. The risk of development of leukemia is theoretically eliminated after hematopoietic cell transplantation (HCT).Simultaneous presence of both host- and donor-derived cells in the recipient often referred to as mixed chimerism (MC) is observed in a large proportion of patients after HCT with non-malignant disorders. In FA patients however, MC might have a unique implication and the persistent existence of FA cells represents a management dilemma as the lingering FA cells may theoretically evolve into a malignant clone. We have studied a large population of FA patients who underwent allogeneic HCT at our institution and report here the outcome of those with MC.From January 1995 until December 2017, 163 FA pts underwent allogeneic HCT at our center; chimerism data at last contact were available on 100 pts who are the subject of this analysis. Females (51) had a mean age at HCT of 8.7 (SD:3.0, Min-Max: 2.0-14.1) years whereas in males (49) it was 8.1 (SD:3.4; Min-Max: 1.4-17.4) years (P-Value: 0.415). Donor was HLA matched family member in 78 pts, Haplo-identical family member in 17 (92 of them were bone marrow and 3 peripheral stem cells); 3 had unrelated cord blood. Total body irradiation was used in 24 pts.Median time to ANC and platelets recovery was 14 and 22 days respectively. Cumulative incidence of overall aGVHD Grade III or above was 4%. Median follow up time was 67.2±14.6 months (95% CI: 38.7-95.7) from HCT date (Min: 7.3, Max:188.1). Chimerism analysis at last follow up showed full chimerism (100%; Myeloid/lymphoid) in 46 pts; 54 had MC defined as the presence of any residual recipient cells. No statistically significant association was noted between full and MC pts in the incidence of aGvHD (P-Value: 0.331). The 10-year cumulative probability of Overall Survival (OS) was 0.904±0.042. No significant difference was observed in OS between full and MC pts (0.954±0.032 vs. 0.883±0.059, P-value: 0.943) with 4 deaths in each group. New malignancy occurred in 4 pts; 2 in each group. In full Chimerism pts: Acute Mixed Lineage Leukemia and carcinoma and in MC pts: acute myeloid leukemia and acute lymphocytic leukemia, (P-Value=1.00). Graft failure occurred in 2 pts in the mixed chimerism group vs none in the full chimerism group (P-Value=1.0).We conclude that mixed chimerism in FA pts does not appear to have an adverse effect on outcome in our follow-up period; longer follow-up time however is needed to confirm the validity of this statement. DisclosuresNo relevant conflicts of interest to declare.

Influence of Donor Type, Stem Cell Source and Conditioning Regimen on Transplant Outcomes after Haploidentical Transplant with Post Transplant Cyclophosphamide for Lymphoma: A Report of the EBMT Lymphoma Working Party

Allogeneic stem cell transplantation (SCT) is potentially curative for patients with lymphoma who progress after autologous SCT. For patients with no HLA identical donor, haploidentical transplant is becoming the major source of alternative donors, particularly with the use of post transplant cyclophosphamide (ptCy). However, there are little data on whether outcomes are affected by the characteristics of the haploidentical donor, the stem cell source or the conditioning. To address this important subject, we identified 474 adult patients (35% females; median age 41 years; range 18-72) with Hodgkin lymphoma (HL-240; 51%), peripheral T cell lymphoma (PTCL-88; 19%), diffuse large B cell lymphoma (DLBCL-77; 16%), mantle cell lymphoma (MCL-40; 8%) or follicular lymphoma (FL-29; 6%), who received a haploidentical SCT (haploSCT) with ptCy between 2010 and 2016 at EBMT participating centers. Patients, donors and transplant characteristics are summarized in Table 1. Median follow-up of alive patients was 32 months (range 3-93).Engraftment by day 100 was successful in 95% of patients. In multivariate Cox analysis (MVA), the use of peripheral blood stem cells (PBSC) positively affected engraftment (HR=1.53; p<0.001). Day 100 acute GVHD (aGVHD) grade II-IV and grade III-IV were diagnosed in 32% and 8% of patients, respectively, and were significantly affected in multivariate analysis by PBSC (HR=2.1 p<0.001 for grade II-IV and HR=4.5 p=0.001 for grade III-IV). The use of sibling haploidentical donors increased the risk of aGVHD grade II-IV (HR=1.87 p=0.01) whereas a CMV negative donor in a positive recipient increased the risk of aGVHD grade III-IV (HR=5.3 p=0.04). The 2-year cumulative incidence of chronic GVHD (cGVHD) and extensive cGVHD were 25% and 9%, respectively. On MVA, male patients had a higher risk of cGVHD and extensive cGVHD (HR =1.7 p=0.03; and 2.8 p=0.04, respectively), whereas a male donor was protective (HR= 0.6 p=0.02; and 0.3 p=0.008, respectively). The risk of cGVHD and extensive cGVHD was also higher for patients in PR (HR 1.7 p=0.03; and 2.4 p=0.04, respectively). The 2-year cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) were 29% and 19%, respectively. In MVA, both CIR and NRM were negatively affected by the lymphoma subtype and by disease status at transplant, both being highest for DLBCL and for advanced disease. Older patient age was associated with a higher NRM but with a lower CIR. The type of conditioning regimen and CMV compatibility also influenced NRM, whereas ABO incompatibility influenced CIR. The 2-year progression free survival (PFS) and overall survival (OS) for HL were 57% and 72% respectively; 54% and 62% for PTCL; 35% and 35% for DLBCL; 52% and 61% for MCL and 56% and 56% for FL. In MVA, CR at SCT significantly improved PFS and OS whereas a diagnosis of DLBCL as well as a CMV donor positive/recipient positive transplant negatively affected PFS and OS.In conclusion, this is the largest study on the influence of donor characteristics, stem cell source and conditioning in haploSCT with ptCy for lymphoma. These results provide critical information to help selecting the best donor in the setting of haploSCT for lymphoma. Our results indicate that the use of PBSC significantly improves engraftment but increases the risk of acute GVHD. Conditioning only influenced NRM but had no effect on PFS or OS. The use of female donors increases the risk of chronic GVHD. Of note, PFS and OS are mostly influenced by disease characteristics (i.e disease status and lymphoma subtype), whereas, with the exception of CMV compatibility, no other donor characteristics (donor age and gender, relationship of the donor to the recipient, degree of HLA mismatch or ABO incompatibility, prior donor pregnancy) impact on PFS or OS, supporting the use of any haplo-identical family member as a donor. DisclosuresTischer:Jazz Pharmaceuticals: Other: Jazz Advisory Board. Mohty:MaaT Pharma: Consultancy, Honoraria. Chalandon:Roche: Membership on an entity's Board of Directors or advisory committees, Other: Travel costs. Sureda:BMS: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Speakers Bureau; Sanofi: Honoraria; Merck: Consultancy, Honoraria; Roche: Honoraria.

Treatment of 30 elderly patients with advanced myeloid neoplasm by allogeneic hematopoietic stem cell transplantation

目的评估异基因造血干细胞移植（allo-HSCT）治疗高龄髓系肿瘤的疗效。方法回顾性分析2014年9月至2017年9月接受allo-HSCT的30例髓系肿瘤患者的临床资料，男16例、女14例，中位年龄58（50~67）岁。急性髓系白血病（AML）18例，慢性粒-单核细胞白血病（CMML）1例，骨髓增生异常综合征（MDS）11例。移植时6例患者完全缓解，其余均为未缓解。亲缘全相合（MRD）12例，非血缘全相合（MUD）6例，单倍型12例。18例患者采用减低剂量预处理方案，12例采用了清髓性预处理方案。结果5例患者在预处理期死亡，24例患者获得造血重建，中性粒细胞、血小板中位植活时间分别为14（10~18）、15（10~19）d。6例患者发生急性GVHD（均为Ⅱ度），8例（32%）患者发生慢性GVHD（中、重度慢性GVHD各1例）。发生巨细胞病毒血症7例，肺部感染7例，皮肤带状疱疹5例，治疗后好转，未出现因感染而死亡的患者。中位随访7（0.5~38）个月，存活21例，预计2年总生存（OS）率为62.5%（95%CI 39.2%~85.8%），无白血病生存率为59.2%（95%CI 26.9%~91.5%）。单因素分析显示，移植时的合并症指数是影响OS的唯一因素。结论allo-HSCT是高龄髓系肿瘤患者比较理想的治疗选择。

Haploidentical Allogeneic Hemopoietic Stem Cell Transplant for High Risk Myelodysplastic Syndrome

▪IntroductionAllogeneic hematoopoietic stem cell transplantation (HSCT) is the only today available curative treatment for Myelodysplastic Syndrome (MDS) patients. Wide approach to transplant has been hampered by HLA compatible donors availability, advanced diseases, donor and patients advanced age.In the recent years improvement of haploidentical HSCT has offered to many patients the opportunity to undergo this curative approach.The Genova transplant team included haplo HSCT for MDS in his standard operative procedure since 2011. Therefore this unselected consecutive patients cohort offers the possibility to verify feasibility of haplo HSCT in MDS patients.Patients and Methods.Form August 2011 since March 2016 thirty (30) consecutive patients were transplanted from an haploidentical donor in our center. All of them were lacking an HLA identical family donor and an 8/8 matched unrelated donor. Table 1 reports patients and disease characteristics.All donors were haploidentical family member. Conditioning regimen was myeloablative for 10 patients and reduced intensity for 20 patients as previously reports (Raiola et al Biol Blood Marrow Transplant. 2013; 1:117-22). Patients received a median of 3.1 x10e8 /kg (range 1.1 -6) un-manipulated marrow derived nucleated cells. Graft versus host disease (GvHD) prophylaxis consisted in post transplant cyclophosphamide 50 mg/kg , on day+3 and +5 , cyclosporine (from day 0) , and micophenolate (from day +1).Data are expressed and median with a range unless indicated. Disease free survival and GvHD rate are calculated with the methods of Kaplan and Meier.ResultsHematologic recovery was complete in 28 (93%) patients. The median times to neutrophil (>500/μL) and platelet recovery (>20,000/μL) was 18 days (range, 14-24 days) and 25 days (range, 12 - 51 days), respectively. Two patients had autologous recovery and were successfully re-transplanted with the same protocol. The incidence of acute GVHD grade II-IV was 15%. No early death was registered. Two patients died, in complete remission of MDS, at 389 (chronic GVHD + sepsis) and 1123 (interstitial pneumonitis) days after transplant, respectively.Seven patients relapsed at median time from transplant of 188 days (range 139 - 560 days). All relapsed patients subsequently died by disease progression.The incidence of chronic GVHD was 20% (6 patients, severe in 5). At the time of this report of the 21 surviving patients (all in remission by MDS) two are under chronic GvHD treatment.With a median follow up of 20.5 months (range 4 - 54) the 3 years probability disease free survival is 69% (95%, CI 51-87).DiscussionHaploidentical transplant, together with conventional donor approach, offers the majority of patients the possibility to undergo HSCT. The data here presented demonstrated feasibility of the procedure in advanced disease patients even by an haploidentical donor. In our knowledge no similar results are achievable by today available or experimental medical therapy. HSCT transplantation, even from haploidentical donor, should be offered to all MDS patients presenting with this indication. Disease relapse is the most important cause of transplant failure. [Display omitted] DisclosuresAngelucci:Novartis oncology, celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Editorial: "How to Improve Cord Blood Transplantation: By Enhancing Cell Counts or Engraftment?".

Editorial: "How to Improve Cord Blood Transplantation: By Enhancing Cell Counts or Engraftment?".

T-cell depleted haploidentical hematopoietic stem cell transplantation is the optimal graft source for patients with familial hemophagocytic lymphohistiocytosis who do not have matched family donors.

Abstract Familial hemophagocytic lymphohistiocytosis (HLH) is a fatal disorder of immune regulation. When managed appropriately with systemic chemotherapy, cure can be achieved by subsequent allogeneic hematopoietic stem cell transplantation (HSCT). Although the best results are obtained with matched-family donors (MFD), alternative donor transplants may be necessary when such donors are not available. As there is urgency to proceed with curative therapy, T-cell depleted haploidentical HSCT could be a viable option as a parent or other haploidentical family member would be available instantly. Between August 2010 and September 2015 we performed haploidentical HSCT for six patients with HLH in this institution. These patients did not have MFDs, and in our center it was logistically easier to perform an haploidentical HSCT rather than to pursue with an unrelated donor or cord blood search from the international registries. The median age at transplant was 6 months (5–31 months) and all had perforin gene mutations. The first two patients had CD3/CD19 depleted procedures while the rest underwent TCR alpha/beta and CD19 depletion for faster immune reconstitution. All six patients engrafted following the transplant with minimal graft versus hot disease. Four patients are cured from the disease with a median follow-up of 3 years (7mths to 5 years). Two patients (siblings) who were transplanted in partial remission expired 2 months following transplant from multi-organ failure after successful engraftment. In the presence of an appropriate transplant laboratory facility, T-cell depleted haploidentical HSCT should be considered as the graft of choice for patients with HLH who do not have HLA-matched family donors.