Post-allogeneic Hematopoietic Stem Cell Research Articles

Comparison of the characteristics of NK cells after two different methods of expansion and observation of the clinical efficacy in patients who relapsed post allogeneic hematopoietic stem cell transplantation

目的比较不同扩增体系NK细胞生物学特性的差异以及治疗异基因造血干细胞移植后（allo-HSCT）白血病复发的疗效。方法分别采用CD3/CD52单抗扩增法和饲养层细胞扩增法诱导供者来源NK细胞大量扩增，检测扩增前后NK细胞表型、因子分泌、细胞毒的变化规律；选取16例allo-HSCT后复发白血病患者，8例输注CD3/CD52单抗扩增NK细胞，8例输注饲养层细胞扩增NK细胞，观察患者的治疗反应和长期生存情况。结果①与CD3/CD52单抗扩增体系相比，饲养层细胞扩增体系NK细胞纯度较高、NK细胞表面活化性受体DNAM-1及NKp30表达较高、抑制性受体CTLA-4表达较低，而两种NK细胞NKG2D/CD25/CD69/Trail/PD-1/TIM-3/TIGIT表达差异无统计学意义。②两种扩增体系NK细胞Ki-67指数均明显增加，以饲养层细胞扩增NK细胞尤为明显；饲养层细胞扩增NK细胞穿孔素及颗粒酶B表达水平均明显高于CD3/CD52单抗扩增NK细胞。③16例allo-HSCT后复发白血病患者NK细胞输注过程中均未观察到明显不良反应。NK细胞输注后中位随访时间为2554（917～2583）d，CD3/CD52单抗扩增组中3例患者无白血病存活，5例死亡；饲养层细胞扩增组中6例患者长期存活，2例死亡。5例患者在NK细胞输注前存在移植物抗宿主病，NK细胞输注后移植物抗宿主病未加重甚至缓解。结论CD3/CD52单抗扩增与饲养层细胞扩增体系NK细胞的生物学特性具有明显差异；NK细胞输注对allo-HSCT后复发白血病患者的疗效仍需要进一步验证。

CD26 expression on donor harvest as a risk predictive biomarker for developing graft-versus-host disease post-allogeneic hematopoietic stem cell transplantation: A ten-year follow-up study.

Allogeneic hematopoietic stem cell transplantation (ASCT) is the preferred treatment option for patients with several hematologic disorders and immunodeficiency syndromes. Graft-versus-host disease (GVHD) is an immune mediated post-transplant complication which has a major impact on long-term transplant outcomes. Current efforts are focused on identification of new markers that serve as potential predictors of GVHD and other post-transplant clinical outcomes. This study includes donor harvests collected from twenty-three allogeneic donors during period 2008-2009 and respective transplant recipients followed for clinical outcomes till March 2019. Percent CD26+ and CD34+ cells in donor harvest were analyzed using flow cytometry. Percent expression and infused dose of CD26+ and CD34+ cells were evaluated for association with various clinical outcomes. Total 23 healthy donors with median age of 28 years (13 males), and transplant recipients with median age of 24years (17 males) formed the study cohort. The diagnosis included malignant (n= 13) and non-malignant (n= 10) hematological disorders. Median CD34brCD45lo HSC expression was 0.57% (IQR 0.24-1.03) while median CD26 expression was 19.64% (IQR 8.96-33.56) of all nucleated cells. CD26 expression was associated with donor age (P= 0.037). CD26 percent expression correlated with WBC engraftment (P= 0.015) and with acute GVHD (P= 0.023) whereas infused CD26 cell dose correlated with WBC engraftment (P= 0.004) and risk of CMV reactivation (P= 0.020). There was no statistically significant correlation of either CD26 expression or cell dose with chronic GVHD, EFS or OS. Our findings suggest a role of CD26 expression on human donor harvest as a potential predictor of acute GVHD. This association warrants further exploration.

Real world outcomes in patients with Philadelphia chromosome positive acute lymphoblastic leukemia undergoing allogeneic stem cell transplantation–A single institution experience

Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) has been associated with a worse prognosis compared to Ph negative ALL. Tyrosine kinase inhibitor (TKI) therapy has led to an improvement in response rates and survival, thus becoming a critical component of therapy. We performed a retrospective cohort study of Ph+ ALL patients treated at the University of Michigan who received TKI therapy pre- and post-allogeneic hematopoietic stem cell transplant (HSCT) from April 2007 to November 2019. The study included 40 patients with Ph+ ALL (47.5% female) with a median age of 54 (24-69) years. Median event-free survival (EFS) was not reached, with a 5-year EFS of 61%. Median overall survival (OS) was not reached, with a 5-year OS of 71%. There was no difference in 2-year EFS or OS for patients on pre-transplant imatinib or dasatinib (p = 0.16, 0.09, respectively), though definitive conclusions are challenging as post-transplant TKI therapy was variable. The incidence of any grade acute graft-versus-host disease (GVHD) was 62.5% (25/40) and any grade chronic GVHD was 77.5% (31/40). Complete molecular remission (CMR) was achieved in 57.5% of patients pre-transplant with no significant difference when stratified by induction TKI (p = 1). Achievement of CMR pre-HSCT showed a trend towards improved 2-year EFS (p=0.0198) but did not significantly change 2-year OS (p = 1). Patients receiving 1st and 2nd generation TKIs pre- and post-HSCT seem to have favorable outcomes, although type of TKI (pre-HSCT) did not significantly impact EFS or OS. In addition, attaining a CMR pre-transplant improved EFS, but did not change OS.

Donor origin precursor B-cell lymphoblastic leukemia post beta-thalassemia haploidentical transplant – A rare case report

Secondary malignancy of donor origin in the form of acute lymphoblastic leukemia (ALL), post-allogeneic hematopoietic stem cell transplant (HSCT) for beta thalassemia (BT) major, is exceedingly rare. A10 year old male child, the first and only product of non-consanguineous conception, was diagnosed with BT major at the age of 9 months when he had diarrhea and his parents (both of whom had thalassemia minor) noticed yellowing of the skin. Until the age of 10 years, he received regular blood transfusion and iron chelation, when the requirements got escalated and he consequently had to undergo myeloablative haploidentical HSCT from his mother. The post-transplant period was uneventful, and follow up with short tandem repeat chimerism analysis revealed complete donor chimerism on all occasions. Five years after the transplant, he developed fever with pancytopenia. Peripheral smear (PS) and bone marrow revealed blasts that were immunophenotypically precursor B-ALL. Cytogenetics revealed twenty diploid female metaphases with modal karyotype 46, XX[20], and again, complete donor chimerism was noted. Thus, a diagnosis of donor cell leukemia (DCL) was considered. Induction chemotherapy was initiated; however, the patient succumbed to systemic sepsis midway through induction therapy. No evidence of leukemia was noted in the patient's mother, who was followed up with PSs for 5 years. DCL has a poor prognosis. Greater understanding of the disease biology could allow for appropriate donor screening, notification and shielding the recipient from DCL and its grave consequences.

Association of early donor chimerism status with survival outcomes in post allogeneic haematopoietic stem cell transplant patients of nonmalignant diseases.

To highlight the association of early donor chimerism status at 2nd month with various survival outcomes. The retrospective study was conducted at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan, and comprised patient data from January 2011 to July 2016. Data related to participants who underwent human leukocyte antigen-matched transplants for bone marrow failure syndrome and beta thalassemia major. Short tandem repeat-based polymerase chain reaction was used to assess donor chimerism status. Overall survival, disease-free survival, relapse-free survival, and graft versus host disease-free survival rates were noted. Data was analysed using SPSS 23. Of the 106, 64(60.4%) had bone marrow failure syndrome and 42(39.6%) had beta thalassemia major. The overall median follow-up was 13.53 months (range: 1.81-62.73 months). Early donor chimerism status was associated with overall survival (p=0.02) and disease-free survival (p=0.01). Mixed donor chimerism was less hazardous in terms of overall survival (p=0.04) and disease-free survival (p=0.02). Early mixed donor chimerism contributed to optimal survival in nonmalignant disease.

High-Dose Intravenous Acyclovir Is Safe and Effective in the Treatment of EBV Reactivation Post Allogeneic Hematopoietic Stem Cell Transplantation

Backgroud:Reactivation of nasopharyngeal carcinoma virus (EBV) post allogeneic hematopoietic stem cell transplantation(allo-HSCT) is very common, but sustained EBV activation maybe induce EBV-associated lymphoproliferative disease (PTLD), transplant-associated hemophagocytic syndrome and thrombocytopenia after transplantation, which is extremely harmful for long-term survival. Currently, the first-line therapeutic strategy for sustained EBV activation is rituximab, but rituximab leads to increased rates of infections and delayed immune reconstitution. Therefore, for the patients with EBV-DNA copies under 1000000/mL, the pros and cons of rituximab are worth weighing.Objective:To evaluate the efficacy and safety of high-dose intravenous acyclovir in the treatment of EBV reactivation post allo-HSCT.Method:Retrospective analysis of clinical data of patients with EBV reactivation post transplantation treated with high-dose intravenous acyclovir (0.5g Q8H) in Sichuan Provincial People's Hospital from January 2019 to May 2021. A total of 49 patients post allo-HSCT from from January 2019 to May 2021 were enrolled in this study. In this population, 38 patients accepted haplo-SCT and 11 patients accepted sibling-SCT. These patients all don't suffer from PTLD and transplant-associated hemophagocytic syndrome, but are resistant to oral antiviral drugs (Acyclovir, valacyclovir, and famciclovir). Simultaneously with intravenous acyclovir, all patients received human immunoglobulin with one dose of 0.4g/kg. The clinical efficacy was evaluated as follows: Overall response(ORR) was defined as the decrease of EBV copies; Complete remission(CR) was defined as the negative turn of EBV copies; Partial response(PR), Stable disease(SD) and Progression of disease(PD) were respectively defined as the decrease, no significant change and increase of EBV copies.Results:The median transplantation time was +86 (+38 to +1587) days. The median number of EBV-DNA copies/ml was 177000 (6620-8200000). After treatment with high-dose intravenous acyclovir, 29 (59.2%) of 49 patients achieved CR, 10 (20.4%) of 49 patients achieved PR, and 10 (20.4%) of 49 patients had no response, including 2 patients with SD and 8 patients with PD. All 49 patients had responded to this regimen with 79.6% ORR. The median time of response and negative turn was 4 days (2 to 11 days) and 9 days (2 to 23 days) respectively. After 100 days for follow-up, 14 of 39 responding patients suffered from EBV activation again, and the EBV copies were higher than that when high-dose acyclovir was initiated. All 24 patients who did not turn negative were recommended with the treatment of rituximab, and 19 of 20 patients who completed treatment turned negative during the three months post acyclovir treatment. The main adverse events (AEs) of this regimen were neutropenia (CTCAE grade 2-3, 8 in 49 patients), thrombocytopenia (CTCAE grade 2-3, 10 in 49 patients), increased serum creatinine (CTCAE grade 1-2, 4 in 49 patients), phlebitis (6 in 49 patients). These AEs were all reversible, which recovered after withdrawal. There was no significant change in the counts of CD4 + T cells and CD8 + T cells before and after intravenous high-dose acyclovir.Conclusion:High-dose intravenous acyclovir is safe and effective in the treatment of EBV reactivation post allo-HSCT, although nearly half of patients still need rituximab treatment. It is a reasonable strategy for patients with oral antiviral resistance. Most patients can avoid the prescription of rituximab in the first six months post allo-HSCT, without interference of immune reconstitution. DisclosuresNo relevant conflicts of interest to declare.

Impact of Concomitant Genetic Abnormalities on Sorafenib Therapy in FLT3-ITD Positive Acute Myeloid Leukemia Undergoing Allo-HSCT

AimIn this study, we investigated the co-occurring mutation landscape in acute myeloid leukemia (AML) patients with FLT3 internal tandem duplication (FLT3-ITD), and explored whether post-allogenic hematopoietic stem cell transplantation (allo-HSCT) sorafenib maintenance therapy could improve the outcomes of FLT3-ITD AML patients combined with other co-occurring genetic abnormalities.MethodsA total of 456 FLT3-ITD AML patients receiving first allo-HSCT were included in this study. Gene mutations were detected using direct sequencing or next generation sequencing. Fusion genes were detected using a 53-gene polymerase chain reaction panel. The frequency of each genetic abnormality was investigated, and the mutation landscape was investigated. The primary outcome of this study was 3-year cumulative incidence of relapse. The secondary outcomes were 3-year overall survival (OS), disease-free survival (DFS) and non-relapse mortality (NRM). The outcomes were compared between patients who received post-HSCT sorafenib maintenance and those who did not in the whole population and in subgroups referring to co-occurring mutations.ResultsA total of 190 patients received post transplantation sorafenib maintenance therapy (sorafenib group) and 266 patients did not (control group). Of the patients receiving sorafenib pre-transplantation, the median duration of sorafenib therapy was 106 days (IQR 68 - 132) in the sorafenib group, and 99 days (IQR 71 - 142) in the control group (p = 0.883). Of the patients receiving post-transplantation sorafenib maintenance therapy, sorafenib was initiated at a median of 30 days (IQR, 30 - 52 days) after allo-HSCT, and continued for a median of 148 days (IQR, 112 - 150).Median follow-up time was 38.7 months (IQR, 28.1 - 47.9). Thirty-four patients in the sorafenib group and 93 patients in the control group relapsed. The 3-year cumulative incidence of relapse was 18.0% (95% CI 13.1% - 24.3%) in the sorafenib group and 36.1% (95% CI 30.5% - 42.3%) in the control group (HR 0.43, 95% CI 0.29 - 0.64; p < 0.001). A total of 126 patients died, including 39 in the sorafenib group and 87 in the control group. Three-year DFS was 75.8% in the sorafenib group and 57.5% in the control group (HR 0.47, 95% CI 0.34 - 0.66; p < 0.001). Three-year OS was 79.5% for patients in the sorafenib group and 68.4% for patients in the control group (HR 0.57, 95% CI 0.39 - 0.83, p = 0.004).Gene mutations were detected using a 12-mutation panel direct sequencing including FLT3-ITD, FLT3-TKD, NPM1, KIT, DNMT3A, CEBPA, ASXL1, TP53, TET2, IDH1, IDH2 and RUNX1 in all patients, and a 127-gene panel new generation sequencing in 188 patients.Except FLT3, a total of 920 co-occurring gene mutations and 147 cytogenetic abnormalties were detected. The co-occurring mutations that presented in at least 10% the cases were NPM1 (31.6%), DNMT3A (15.4%), TET2 (11.4%), and CEBPA (10.5%). There were 10.5% patients presented with both NPM1 and DNMT3A mutations (Triple-mutated AML patients), and 13.8% patients combined with at least one additional genetic abnormality classified as adverse according to the 2017 ELN risk stratification other than FLT3-ITD. Cytogenetic abnormalities presented in more than 1% the patients were RUNX1-RUNX1T1, which occurred in 23 patients (5.0%), followed by +8 (2.9%), complex karyotype (2.6%), CBFB-MYH11 (2.4%), DEK-NUP214 (1.3%) and -y (1.3%).Patients combined with NPM1(p = 0.009 and 0.009), DNMT3A (p = 0.036 and 0.086), triple-mutated AML patients (p = 0.030 and 0.027), and patients with at least one additional adverse abnormality (p = 0.014 and 0.005) benefit significantly in DFS and OS from post-transplantation sorafenib maintenance, but not those with CEBPA (p = 0.669 and 0.576) or TET2 (p = 0.375 and 0.178) mutations.ConclusionPost transplantation sorafenib maintenance therapy can improve the prognosis of FLT3-ITD AML patients combined with DNMT3A or NPM1, patients with triple-mutated AML, and patients combined with at least one additional adverse abnormalities, but not of those combined with CEBPA or TET2 mutations. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Large-vessel vasculitis in graft-versus-host disease: a case report

BackgroundGraft-versus-host disease is a common complication seen with allogenic stem cell transplant, which is used to treat a variety of hematological malignancies. Graft-versus-host disease is an allogenic syndrome and can present in a variety of ways, including symptoms mimicking various autoimmune diseases; however, it is quite rare to see graft-versus-host disease affecting the vascular system and causing vasculitis.Case presentationWe describe a case of a 59-year-old Caucasian man with follicular lymphoma and diffuse large B-cell transformation who developed graft-versus-host disease post allogenic hematopoietic stem cell transplantation and later progressed to neurological complication foot drop and large-vessel vasculitis.ConclusionThe life-threatening vascular complications associated with large-vessel vasculitis include arterial aneurysms and dissections, and ischemic or hemorrhagic stroke. Thus, this rare immunological association needs to be recognized and treated in a timely manner to prevent the long-term complications.

Metabolomic identification of α-ketoglutaric acid elevation in pediatric chronic graft-versus-host disease

AbstractChronic graft-versus-host disease (cGVHD) is the most common cause for non-relapse mortality postallogeneic hematopoietic stem cell transplant (HSCT). However, there are no well-defined biomarkers for cGVHD or late acute GVHD (aGVHD). This study is a longitudinal evaluation of metabolomic patterns of cGVHD and late aGVHD in pediatric HSCT recipients. A quantitative analysis of plasma metabolites was performed on 222 evaluable pediatric subjects from the ABLE/PBMTC1202 study. We performed a risk-assignment analysis at day + 100 (D100) on subjects who later developed either cGVHD or late aGVHD after day 114 to non-cGVHD controls. A second analysis at diagnosis used fixed and mixed multiple regression to compare cGVHD at onset to time-matched non-cGVHD controls. A metabolomic biomarker was considered biologically relevant only if it met all 3 selection criteria: (1) P ≤ .05; (2) effect ratio of ≥1.3 or ≤0.75; and (3) receiver operator characteristic AUC ≥0.60. We found a consistent elevation in plasma α-ketoglutaric acid before (D100) and at the onset of cGVHD, not impacted by cGVHD severity, pubertal status, or previous aGVHD. In addition, late aGVHD had a unique metabolomic pattern at D100 compared with cGVHD. Additional metabolomic correlation patterns were seen with the clinical presentation of pulmonary, de novo, and progressive cGVHD. α-ketoglutaric acid emerged as the single most significant metabolite associated with cGVHD, both in the D100 risk-assignment and later diagnostic onset analysis. These distinctive metabolic patterns may lead to improved subclassification of cGVHD. Future validation of these exploratory results is needed. This trial was registered at www.clinicaltrials.gov as #NCT02067832.

Salvage Therapy With Low-Dose Ruxolitinib Leads to a Significant Improvement in Bronchiolitis Obliterans Syndrome in Patients With cGVHD After Allogeneic Hematopoietic Stem Cell Transplantation.

Bronchiolitis obliterans syndrome (BOS) is a life-threatening pulmonary manifestation of chronic graft versus host disease (cGVHD) post-allogeneic hematopoietic stem cell transplantation (HSCT), without clear standard of care. This study included 30 patients undergoing an allogeneic HSCT for a hematological malignancy and the outcomes with post-HSCT BOS treated with ruxolitinib as a salvage treatment were reviewed. After a median duration of ruxolitinib therapy of 9.25 (1.5–27) months, the best overall response (BOR) rate was 66.7%: three patients (10.0%) achieved complete remission, and 17 (56.7%) achieved partial remission. The median time from initiation of ruxolitinib to achieve the best responses was 3 months. Since initiating ruxolitinib, forced expiratory volume in 1 s of predicted (FEV1%pred) slightly increased after 3 and 6 months compared with measurements before ruxolitinib in responders. Only FEV1%pred mild decline before ruxolitinib with a ratio ≤15% was an independent predictor to achieve a response to ruxolitinib. Eleven patients (36.7%) had severe pulmonary infection of ≥3 grade. Following a median follow-up of 318 days after ruxolitinib, the 2-years incidence of nonrelapse mortality and 2-years overall survival rate after ruxolitinib among patients with BOS was 25.1 and 62.6%, respectively. Ruxolitinib is a promising treatment option to improve the prognosis of post-HSCT BOS.

Highlighting the Prognostic Importance of Measurable Residual Disease Among Acute Myeloid Leukemia Risk Factors

Objective:The optimal timing of measurable residual disease (MRD) evaluation in acute myeloid leukemia (AML) patients has not been well defined yet. We aimed to investigate the impact of MRD in pre- and post-allogeneic hematopoietic stem cell transplantation (AHSCT) periods on prognostic parameters.Materials and Methods:Seventy-seven AML patients who underwent AHSCT in complete morphological remission were included. MRD analyses were performed by 10-color MFC and 10-4 was defined as positive. Relapse risk and survival outcomes were assessed based on pre- and post-AHSCT MRD positivity.Results:The median age of the patients was 46 (range: 18-71) years, and 41 (53.2%) were male while 36 (46.8%) were female. The median follow-up after AHSCT was 12.2 months (range: 0.2-73.0). The 2-year overall survival (OS) in the entire cohort was 37.0%, with a significant difference between patients who were MRD-negative and MRD-positive before AHSCT, estimated as 63.0% versus 16.0%, respectively (p=0.005). MRD positivity at +28 days after AHSCT was also associated with significantly inferior 2-year OS when compared to MRD negativity (p=0.03). The risk of relapse at 1 year was 2.4 times higher (95% confidence interval: 1.1-5.6; p=0.04) in the pre-AHSCT MRD-positive group when compared to the MRD-negative group regardless of other transplant-related factors, including pre-AHSCT disease status (i.e., complete remission 1 and 2). Event-free survival (EFS) was significantly shorter in patients who were pre-AHSCT MRD-positive (p=0.016). Post-AHSCT MRD positivity was also related to an increased relapse risk. OS and EFS were significantly inferior among MRD-positive patients at +28 days after AHSCT (p=0.03 and p=0.019).Conclusion:Our results indicate the importance of MRD before and after AHSCT independently of other factors.

A novel clinically relevant graft-versus-leukemia model in humanized mice.

The prognosis for acute myeloid leukemia (AML) relapse post allogeneic hematopoietic stem cell transplantation (alloSCT) is dismal. Novel effective treatment is urgently needed. Clinical benefit of alloSCT greatly relies on the graft-versus-leukemia (GVL) effect. The mechanisms that mediate immune escape of leukemia (thus causing GVL failure) remain poorly understood. Studies of human GVL have been hindered by the lack of optimal clinically relevant models. Here, using our large, longitudinal clinical tissue bank that include AML cells and G-CSF mobilized donor hematopoietic stem cells (HSCs), we successfully established a novel GVL model in humanized mice. Donor HSCs were injected into immune-deficient NOD-Cg-Prkdcscid IL2rgtm1Wjl /SzJ (NSG) mice to build humanized mice. Immune reconstitution in these mice recapitulated some clinical scenario in the patient who received the corresponding HSCs. Allogeneic but HLA partially matched patient-derived AML cells were successfully engrafted in these humanized mice. Importantly, we observed a significantly reduced (yet incomplete elimination of) leukemia growth in humanized mice compared with that in control NSG mice, demonstrating a functional (but defective) GVL effect. Thus, for the first time, we established a novel humanized mouse model that can be used for studying human GVL responses against human AML cells in vivo. This novel clinically relevant model provides a valuable platform for investigating the mechanisms of human GVL and development of effective leukemia treatments.

Is There a Place for PD-1-PD-L Blockade in Acute Myeloid Leukemia?

Checkpoint inhibitors were a major breakthrough in the field of oncology. In September 2014, based on the KEYNOTE-001 study, the Food and Drug Administration (FDA) approved pembrolizumab, a programmed cell death protein 1 (PD-1) inhibitor, for advanced or unresectable melanoma. Up until now, seven PD-1/PD-ligand(L)-1 inhibitors are approved in various solid cancers and hundreds of clinical studies are currently ongoing. In hematology, PD-1 inhibitors nivolumab and pembrolizumab were approved for the treatment of relapsed/refractory (R/R) classic Hodgkin lymphoma, and later pembrolizumab was approved for R/R primary mediastinal large B-cell lymphoma. In acute myeloid leukemia (AML), the combination of hypomethylating agents and PD-1/PD-L1 inhibitors has shown promising results, worth of further investigation, while other combinations or single agent therapy have disappointing results. On the other hand, rather than in first line, these therapies could be useful in the consolidation or maintenance setting, for achieving minimal residual disease negativity. Furthermore, an interesting application could be the use of PD-1/PD-L1 inhibitors in the post allogeneic hematopoietic stem cell transplantation relapse. There are several reasons why checkpoint inhibitors are not very effective in treating AML, including the characteristics of the disease (systemic, rapidly progressive, and high tumor burden disease), low mutational burden, and dysregulation of the immune system. We here review the results of PD-1/PD-L1 inhibition in AML and discuss their potential future in the management of this disease.

Sexuality- and Fertility-Related Issues in Women after Allogeneic Hematopoietic Stem Cell Transplantation

Sexual dysfunction and fertility related issues appear as major post-allogeneic hematopoietic stem cell transplantation (HSCT) late effects in young women, with a heavy impact on quality of life. The objective of the present study was to evaluate the impact of disease and treatments on sexual quality of life, ovarian function, and family planning initiatives in the context of allogeneic HSCT. Between January 2014 and January 2016, adult female patientswho underwent HSCT before age 35 and had been followed formore than 2 years in our centerwere offered participation inthe study through a self-reported surveyand/or ovarian function assessment if age <40 at inclusion. A total of 63 patients were included, with a median age of 23.4 years at transplantation and 30.9 years at inclusion. Twenty-nine patients (46%) underwent HSCT for acute leukemia and 16 (25%) underwent HSCT for aplastic anemia (AA). The conditioning regimen was myeloablative conditioning (MAC) in 37 patients (59%) and reduced-intensity conditioning (RIC) in 26 (41%). Fifty-eight patients completed the survey, and 34 were evaluated for ovarian function. Symptoms of hypoestrogenism were reported by 86% of the patients and changes in sexual life were reported by 76%, due mainly to low sex drive, negative impact of infertility problems, physical sequelae, and loss of self-confidence. Premature ovarian failure (POF) occurred in 74% of patients and was significantly associated with conditioning regimen (MACversusRIC; P=.001) and baseline disease (bone marrow failureversusacute leukemiaversusothers; P < .001). However, one-half of the patients developed a POF despite the use of a RIC regimen. For 27 patients (47%), disease and treatments modified their desire for pregnancy, due mainly to fear of relapse and of disease transmission to offspring. Thirteen pregnancies were reported (21%), of which 8 were spontaneous and 5 were obtained through assisted reproductive technologies, mainly oocyte donation. With a median post-transplantation follow-up of 12.2 years, the 10-year cumulative incidence of first pregnancy was 16.6% (95% CI, 8.8-30.0). Among 20 patients (32%) who engaged in a family planning initiative, 13 (65%) succeeded in having children: 11 got pregnant and 2 adopted. Sixteen patients benefited from fertility preservation techniques consisting of ovarian tissue cryopreservation, and a single autologous ovarian tissue transplantation had been performed at the time of this report. This study shows a strong impact of disease and treatments on sexual quality of life, ovarian function, and family planning initiatives in the context of HSCT. It demonstrates the need to improve clinicians' awareness of sexual health- and fertility-related issues after HSCT. The difficulty of predicting ovarian function and fertility issues after RIC supports wide indications of pretransplantation fertility preservation. Evaluation of the use of cryopreserved ovarian tissues is warranted.

Post-allogeneic hematopoietic stem cell transplantation viral reactivations and viremias: a focused review on human herpesvirus-6, BK virus and adenovirus.

Human cytomegalovirus and Epstein–Barr virus have been recognized as potential drivers of morbidity and mortality of patients undergoing allogeneic stem cell transplantation for years. Specific protocols for monitoring, prophylaxis and pre-emptive therapy are in place in many transplant settings. In this review, we focus on the next three most frequent viruses, human herpesvirus-6, BK virus and adenovirus, causing reactivation and/or viremia after allogeneic transplant, which are increasingly detected in patients in the post-transplant period owing to emerging techniques of molecular biology, recipients’ characteristics, treatment modalities used for conditioning and factors related donors or stem cell source. Given the less frequent detection of an illness related to these viruses, there are often no specific protocols in place for the management of affected patients. While some patients develop significant morbidity (generally older), others may not need therapy at all (generally younger or children). Furthermore, some of the antiviral therapies used are potentially toxic. With the addition of increased risk of secondary infections, risk of graft failure or increased risk of graft-versus-host disease as well as the relationship with other post-transplant complications, the outcomes of patients with these viremias remain unsatisfactory and even long-term survivors experience increased morbidity.

Prognostic impact of circulating tumor DNA status post-allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia and myelodysplastic syndromes

Relapse is an issue of concern for patients with acute myeloid leukemia and myelodysplastic syndromes (AML/MDS) who underwent allogeneic hematopoietic stem cell transplantation (allo HSCT). The conventional minimal residual disease (MRD) test of the bone marrow has serious limitations regarding invasiveness and applicability. To address this problem, we investigated the utility of a novel MRD test using tumor-derived fragmentary DNA, or circulating tumor DNA (ctDNA) for the identification of patients with high risk of AML/MDS relapse after undergoing myeloablative allo HSCT. We retrospectively collected tumor specimens and available matched serum samples at diagnosis and at 1 and 3 months post-allo HSCT from 53 patients with AML/MDS. After identifying driver mutations in 51 patients using next-generation sequencing, we designed at least one personalized digital polymerase chain reaction assay per case. Diagnostic ctDNA and matched tumor DNA exhibited excellent correlations with variant allele frequencies. Sixteen patients relapsed after a median of 7 months post allo HSCT. Both the mutation persistence in the bone marrow at 1 and 3 months post allo HSCT and the corresponding ctDNA persistence in the matched serum were comparably associated with higher 3-year cumulative incidence of relapse rates. These results demonstrate, for the first time, the utility of ctDNA as a noninvasive prognostic biomarker in patients with AML/MDS who underwent allo HSCT.

1088. Extracorporeal Photopheresis and Infectious Complications in Patients with Chronic Graft Versus Host Disease

BackgroundExtracorporeal photopheresis (ECP), is a cell-based immune-modulatory therapy used in the treatment of steroid refractory chronic graft versus host disease (cGHVD). It is unclear whether ECP is associated with an increased risk of infections compared to alternative treatment. We aimed to study the infectious complications in patients who are on ECP post allogeneic hematopoietic stem cell transplant (alloHSCT).MethodsWe conducted a retrospective cohort study of adult patients with cGVHD post alloHSCT who were initiated on ECP or second line immunosuppressive agents (SLIS). The study period was from March 1, 2014 to October 1, 2018. Each subject in the ECP arm was matched to the SLIS arm according to gender, age, underlying disease, and date of diagnosis of cGVHD. All subjects were followed for one-year post treatment. The main outcome was incidence of each type of infection (event rate/ person-years). Kaplan Meier analysis was used, evaluating time to infection with log rank test. The spectrum of infectious complications was described.ResultsSeventy-seven patients were included (36 in ECP and 41 in SLIS arm). Median age was 57.4 years (18.1 -73.4), and 59.7% of patients were male. The most common underlying diseases were acute myeloid leukemia (45.4%), myelodysplastic syndrome (20.8%) and non-Hodgkin’s lymphoma (15.6%). A total occurrence of 94 infections was observed in the ECP arm, compared to 118 in SLIS arm. Bacterial infections accounted for majority of the infections in ECP arm (50%) compared to SLIS arm in which viruses were most common (49.2%). Bacterial pneumonia was the most common clinical syndrome (34% and 27.3%, in the ECP and SLIS arms, respectively). Bacteremia accounted for 12.8% of infections in the ECP arm compared to 16.4% in the SLIS arm. There was no difference in the event rates of infections among the two groups [2.58/ person-years in ECP group vs 3.60/person-years, p = 0.3766], or the probability of infection at any time between the ECP and SLIS group on Kaplan Meier (log rank test, p-value=0.36)(Figure 1).Kaplan-Meier plot of time to the earliest infection diagnosis between ECP and control group ConclusionBacterial and viral pneumonia were the most common infections in patients undergoing ECP. Overall, ECP does not confer an increased risk of infectious complications compared to second line IS agents.Disclosures Wissam El Atrouni, MD, ViiV (Advisor or Review Panel member)

Evaluation of Next-Generation Sequencing and Crystal Digital PCR for Chimerism Monitoring of Post-Allogeneic Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is a curative treatment for most hematologic diseases. To evaluate the level of donor engraftment, chimerism must be carefully monitored after HSCT. Short tandem repeats, quantitative PCR (qPCR), and, more recently, digital PCR (dPCR) are widely used to determine the proportions of donor and recipient cells after HSCT. The screening and quantification of chimerism have been evaluated by 2 new methods: a ready-to-use next-generation sequencing (NGS)-based method using the Devyser ChimerismNGS kit and an original combination of the Stilla crystal digital PCR (cdPCR) platform with 3-color multiplexing capacity using GenDX KMRtrack reagents. The genotyping of 4 HSCT pairs by cdPCR using 11 triplex mixes of the GenDX KMRtype kit was consistent at 98.8% with qPCR. Informative samples (n=20) from 6 donor-recipient pairs and 1 external proficiency test demonstrated the reliability of the results (0.1% to 50%) for the 2 methods. The methods are also highly sensitive (0.1%) and accurate. The chimerism values of the 2 methods are correlated and concordant with those of the reference methods. In addition, the ADVYSER software (Devyser) is user-friendly and well adapted to chimerism monitoring. In conclusion, these 2 innovative methods are easy to perform and user-friendly in all molecular, hematology, and immunogenetic laboratories and allow the genotyping and monitoring of chimerism with high performance and sensitivity.

The impact of chimerism on DNA-based human identification from skin surface cells of post-allogenic hematopoietic stem cell transplantation (HCST) patients

The use of biological traces recovered from touched or handled items increased with the advance of the forensic analysis system. Thus, DNA profiles obtained from touch DNA became a useful tool in forensic investigation. However, a chimeric person with more than one chromosomal population can be challenging for a forensic analyst. We investigated the genetic profile in blood, buccal swab, and skin swabs from twenty-four recipients aged 21–63 years who underwent a matched sibling allogeneic hematopoietic stem cell transplantation with no sign of skin graft versus host disease. Autosomal short tandem repeats genotyping was performed to evaluate chimerism status at 15 loci along with gender marker Amelogenin. According to our results, donor chimerism was detected in all recipient's blood samples, while in buccal swabs, five recipients showed no presence of donor-derived cells in their genotype. Epithelial cells swabbed from hand fingertips were not devoid of donor-derived cells since all recipients showed high chimerism (39.69%–96.66%) in their genotypes. A significant change in chimerism was seen among various types of biological samples (p<0.05). No correlations were observed between chimerism and recipient age, gender, or time after transplant (p> 0.05). The loci D21S11, D8S1179, and FGA were the most informative, whereas D13S317, Vwa, and TOPX were the least informative STR markers. We concluded that touch DNA from a person who has undergone a successful allogeneic HSCTs should not be considered as reliable evidence for human identifications. Therefore, necessary precautions must be taken to avoid false identification and miscarriage of justice.

Early and late-onset veno-occlusive disease/sinusoidal syndrome post allogeneic stem cell transplantation - a real-world UK experience.

Classical veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a serious complication post allogeneic hematopoietic stem cell transplantation (HSCT). Before the recently revised EBMT criteria, the Baltimore and modified Seattle criteria failed to recognize the syndrome of late-onset VOD. We present real-world experience from a large UK transplant center reporting on VOD/SOS in consecutive HSCT adult patients (n = 530), transplanted for hematological cancers. We identified 27 patients treated with Defibrotide for VOD/SOS diagnosis, where detailed data were available for final analysis. Using standard definitions including EBMT criteria, around 30% (n = 8/27) of cases classified as late-onset VOD presenting at median of 46 (22-93) days but with D100 survival (63% vs 58%, Log-rank; P = 0.81) comparable to classical VOD. Hazard ratio for D100 mortality was 2.82 (95% CI: 1.74-4.56, P<.001, Gray test) with all VOD/SOS events. Twenty percent (n = 2/8) of late-onset VOD patients were anicteric and 42% (n = 8) classical VOD patients presented with refractory thrombocytopenia, while less than half met EBMT criteria for classical VOD in adults, highlighting gaps in real-world diagnostic limitations using EBMT criteria. However, challenges remain about underrecognition and difficulties related to early defibrotide access for treatment of late-onset VOD in current treatment guidelines. Our report strongly supports early Defibrotide for the treatment of severe VOD/SOS in adults regardless of time of onset.