Hepatic Veno-Occlusive Disease after Hematopoietic Stem Cell Transplantation: Risk Factors and Stratification, Prophylaxis, and Treatment

Endothelial injury and dysfunction with emerging immunotherapies in multiple myeloma, the impact of COVID-19, and endothelial protection with a focus on the evolving role of defibrotide

Patients with multiple myeloma (MM) were among the groups impacted more severely by the COVID-19 pandemic, with higher rates of severe disease and COVID-19-related mortality. MM and COVID-19, plus post-acute sequelae of SARS-CoV-2 infection, are associated with endothelial dysfunction and injury, with overlapping inflammatory pathways and coagulopathies. Existing treatment options for MM, notably high-dose therapy with autologous stem cell transplantation and novel chimeric antigen receptor (CAR) T-cell therapies and bispecific T-cell engaging antibodies, are also associated with endothelial cell injury and mechanism-related toxicities. These pathologies include cytokine release syndrome (CRS) and neurotoxicity that may be exacerbated by underlying endotheliopathies. In the context of these overlapping risks, prophylaxis and treatment approaches mitigating the inflammatory and pro-coagulant effects of endothelial injury are important considerations for patient management, including cytokine receptor antagonists, thromboprophylaxis with low-molecular-weight heparin and direct oral anticoagulants, and direct endothelial protection with defibrotide in the appropriate clinical settings.

Review of imaging findings in hepatic veno-occlusive disease

Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a potentially life-threatening complication of hematopoietic stem cell transplantation. Patients present with right upper-quadrant abdominal pain, jaundice, weight gain, and conjugated hyperbilirubinemia. Early diagnosis of VOD is essential to promptly initiate defibrotide therapy, which has been demonstrated to enhance survival and achieve complete resolution of disease in some patients. Historically, VOD was diagnosed by the modified Seattle or Baltimore criteria, which are both based on clinical symptoms. Alongside advancements in medical imaging over the last 40 years, the diagnosis of VOD has evolved to include the use of ultrasound, elastography, cross-sectional imaging, and image guided biopsy. Identification and interpretation of findings of VOD across imaging modalities is now a critical aspect of post-HSCT care. This review will outline the imaging findings and recommendations for the use of imaging in the management of VOD including gray-scale, color and spectral Doppler ultrasound, ultrasound elastography, CT, MRI, and liver biopsy.

The Impact of Pretransplant Use of Tyrosine Kinase Inhibitors on Allogeneic Stem Cell Transplantation in Patients with Chronic Myeloid Leukemia - A Single-institution Retrospective Study

Objective Chronic myeloid leukemia (CML) is a malignant hematological disorder, and allogeneic stem cell transplantation (allo-SCT) was its only curative treatment until the introduction of tyrosine kinase inhibitors (TKIs). Allo-SCT is still considered for CML patients who are resistant to TKIs and in an advanced phase. Currently, second- and third-generation (2/3G TKIs are typically incorporated into the first-line treatment of CML. However, the impact of 2/3G TKIs on subsequent allo-SCT remains unclear. We therefore evaluated the effect of 2/3G TKIs on allo-SCT. Methods We retrospectively evaluated the effect of pretransplant therapy with TKIs on the outcome of allo-SCT for CML using clinical data at our institution. Patients Thirty-two CML patients who received their first allo-SCT procedure at our institute from 2001 to 2020 were included. We divided the patients into three subgroups based on TKI treatment before allo-SCT. Patients receiving no TKIs, only imatinib (IM), and 2/3G TKIs were classified into the Non-TKI, IM, and 2/3G TKI groups, respectively. Results In a univariate analysis, the pretransplant use of 2/3G TKIs was significantly associated with a higher 5-year overall survival (91.7%) and relapse-free survival (75.0%) than the use of IM (37.5% and 12.5%) in patients presenting with or progressing to the advanced phase. In addition, pretransplant use of 2/3G TKIs did not increase the incidence of graft-versus-host disease (GVHD). Conclusion We demonstrated that the pretransplant use of 2/3G TKIs was safe and improved the outcome of CML patients who presented with or progressed to the advanced phase without increasing the frequency of GVHD.

Clinical features and risk factors of hepatic sinusoidal obstruction syndrome in children after hematopoietic stem cell transplantation: A single-center experience

Hepatic sinusoidal obstruction syndrome (SOS) is an illness with serious life effects that develops after hematopoietic stem cell transplantation (HSCT). We investigated the risk factors and clinical features of hepatic SOS in children following HSCT in 210 children who underwent allogeneic or autologous HSCT between 2009 and 2021 were analyzed in the context of SOS. The syndrome developed in 22 (10.4%) patients:frequently in neuroblastoma [24% (5/21)], hemophagocytic lymphohistiocytosis [57% (4/7)], and thalassemia major [22% (7/31)]. The median time from HSCT to diagnosis was 16 (6-38) days. Severe disease occurred in 8 (36%) patients, and mild/moderate in 14 (64%) and 4 patients died (18%). In univariate analyses, patient's age ≤ 2 years [odds ratio (OR)= 3.043, P = 0.028], pretransplant AST and ALT levels > 100 U/L (OR=3.576, P = 0.045), and chemotherapy/radiotherapy to abdomen before transplantation (OR = 3.162, P = 0.044) were determined as risk factors. In multivariate analysis, pre-transplant AST and ALT levels > 100 U/L (OR = 16.04, P = 0.010) and ferritin levels over 1000 mg/dl (OR=5.15, P = 0.047) were significant. The only independent risk factor on mortality was the age ≤ 2 years (P = 0.001). Although our study confirmed several risk factors for SOS, we failed to achieve some well-known risk factors. Precautions should be taken considering the factors affecting liver function before transplantation and the risk of SOS in infants receiving chemotherapy and radiotherapy before transplantation, such as neuroblastoma in which comparable results in respect to the chemotherapy only. The risk factors should be fully elucidated in multicenter studies to improve preventive and therapeutic strategies.

Restrictive versus liberal red blood cell transfusion strategies for people with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without haematopoietic stem cell support

BACKGROUND

An estimated one-quarter to one-half of people diagnosed with haematological malignancies experience anaemia. There are different strategies for red blood cell (RBC) transfusions to treat anaemia. A restrictive transfusion strategy permits a lower haemoglobin (Hb) level whereas a liberal transfusion strategy aims to maintain a higher Hb. The most effective and safest strategy is unknown.

OBJECTIVES

To determine the efficacy and safety of restrictive versus liberal RBC transfusion strategies for people diagnosed with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without a haematopoietic stem cell transplant (HSCT).

SEARCH METHODS

We searched for randomised controlled trials (RCTs) and non-randomised studies (NRS) in MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1982), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2023, Issue 2), and eight other databases (including three trial registries) to 21 March 2023. We also searched grey literature and contacted experts in transfusion for additional trials. There were no language, date or publication status restrictions.

SELECTION CRITERIA

We included RCTs and prospective NRS that evaluated restrictive versus liberal RBC transfusion strategies in children or adults with malignant haematological disorders receiving intensive chemotherapy or radiotherapy, or both, with or without HSCT.

DATA COLLECTION AND ANALYSIS

Two authors independently screened references, full-text reports of potentially relevant studies, extracted data from the studies, and assessed the risk of bias. Any disagreement was discussed and resolved with a third review author. Dichotomous outcomes were presented as a risk ratio (RR) with a 95% confidence interval (CI). Narrative syntheses were used for heterogeneous outcome measures. Review Manager Web was used to meta-analyse the data. Main outcomes of interest included: all-cause mortality at 31 to 100 days, quality of life, number of participants with any bleeding, number of participants with clinically significant bleeding, serious infections, length of hospital admission (days) and hospital readmission at 0 to 3 months. The certainty of the evidence was assessed using GRADE.

MAIN RESULTS

Nine studies met eligibility; eight RCTs and one NRS. Six hundred and forty-four participants were included from six completed RCTs (n = 560) and one completed NRS (n = 84), with two ongoing RCTs consisting of 294 participants (260 adult and 34 paediatric) pending inclusion. Only one completed RCT included children receiving HSCT (n = 6); the other five RCTs only included adults: 239 with acute leukaemia receiving chemotherapy and 315 receiving HSCT (166 allogeneic and 149 autologous). The transfusion threshold ranged from 70 g/L to 80 g/L for restrictive and from 80 g/L to 120 g/L for liberal strategies. Effects were reported in the summary of findings tables only for the trials that included adults to reduce indirectness due to the limited evidence contributed by the prematurely terminated paediatric trial. Evidence from RCTs Overall, there may be little to no difference in the number of participants who die within 31 to 100 days using a restrictive compared to a liberal transfusion strategy, but the evidence is very uncertain (three studies; 451 participants; RR 1.00, 95% CI 0.27 to 3.70, P=0.99; very low-certainty evidence). There may be little to no difference in quality of life at 0 to 3 months using a restrictive compared to a liberal transfusion strategy, but the evidence is very uncertain (three studies; 431 participants; analysis unable to be completed due to heterogeneity; very low-certainty evidence). There may be little to no difference in the number of participants who suffer from any bleeding at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (three studies; 448 participants; RR 0.91, 95% CI 0.78 to 1.06, P = 0.22; low-certainty evidence). There may be little to no difference in the number of participants who suffer from clinically significant bleeding at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (four studies; 511 participants; RR: 0.94, 95% CI 0.74 to 1.19, P = 0.60; low-certainty evidence). There may be little to no difference in the number of participants who experience serious infections at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (three studies, 451 participants; RR: 1.20, 95% CI 0.93 to 1.55, P = 0.17; low-certainty evidence). A restrictive transfusion strategy likely results in little to no difference in the length of hospital admission at 0 to 3 months compared to a liberal strategy (two studies; 388 participants; analysis unable to be completed due to heterogeneity in reporting; moderate-certainty evidence). There may be little to no difference between hospital readmission using a restrictive transfusion strategy compared to a liberal transfusion strategy (one study, 299 participants; RR: 0.89, 95% CI 0.52 to 1.50; P = 0.65; low-certainty evidence). Evidence from NRS The evidence is very uncertain whether a restrictive RBC transfusion strategy: reduces the risk of death within 100 days (one study, 84 participants, restrictive 1 death; liberal 1 death; very low-certainty evidence); or decreases the risk of clinically significant bleeding (one study, 84 participants, restrictive 3; liberal 8; very low-certainty evidence). No NRS reported on the other eligible outcomes.

AUTHORS' CONCLUSIONS

Findings from this review were based on seven studies and 644 participants. Definite conclusions are challenging given the relatively few included studies, low number of included participants, heterogeneity of intervention and outcome reporting, and overall certainty of evidence. To increase the certainty of the true effect of a restrictive RBC transfusion strategy on clinical outcomes, there is a need for rigorously designed and executed studies. The evidence is largely based on two populations: adults with acute leukaemia receiving intensive chemotherapy and adults with haematologic malignancy requiring HSCT. Despite the addition of 405 participants from three RCTs to the previous review's results, there is still insufficient evidence to answer this review's primary outcome. If we assume a mortality rate of 3% within 100 days, we would need a total of 1492 participants to have an 80% chance of detecting, at a 5% level of significance, an increase in all-cause mortality from 3% to 6%. Further RCTs are needed overall, particularly in children.

Prevention and management of acute toxicities from conditioning regimens during hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) remains the only curative option for several hematological malignancies. Its use has continued to grow, with an estimated 23,500 transplants performed annually in the United States alone. The acute toxicities that occur from conditioning chemotherapy can impact the peri-transplant period and have substantial implications on patients' tolerability and outcomes, irrespective of the treatment of their disease. Chemotherapy-induced nausea vomiting (CINV), mucositis, transplant-associated thrombotic microangiopathy (TA-TMA), and sinusoidal obstruction syndrome, also known as a veno-occlusive disease (SOS/VOD) can all have significant implications for patients. These acute complications begin with the start of conditioning chemotherapy and add to potential toxicity for patients throughout the early post-transplant period, from Day +30 for CINV, mucositis, and SOS, and which can continue through at least Day +100 with the onset of TA-TMA. These toxicities must be prevented and managed appropriately. This review will summarize the literature surrounding them and guide their management.

Utility of liver stiffness measurement in the diagnosis of sinusoidal obstruction syndrome/veno-occlusive disease after hematopoietic stem cell transplantation

PURPOSE

We aimed to assess the role of liver stiffness measurement (LSM), evaluated using transient elastography (TE), for the diagnosis of sinusoidal obstruction syndrome (SOS)/veno-occlusive disease (VOD), a complication of hematopoietic stem cell transplantation (HSCT).

METHODS

In this retrospective study, ultrasonography (US) and LSM were performed on 86 adult patients (55 men and 31 women) undergoing HSCT between January 2016 and December 2022. Characteristics and changes in liver stiffness (LS) were compared between patients with and without SOS/VOD.

RESULTS

Of the 86 patients, 14 were diagnosed with SOS/VOD. A significant increase in LS (ranging from 12.6 to 55.1 kPa, median 23.8 kPa) compared to pre-HSCT values was observed in all patients who developed SOS/VOD. The area under the receiver operating characteristic curve (AUROC) for the diagnosis of SOS/VOD was 0.9663 (0.933-0.995) for LS ≥ 17.4 kPa after HSCT. Post-transplant LS exceeded 17.4 kPa in all 14 patients in the SOS/VOD group (100%) and in seven patients in the non-SOS/VOD group (9.7%). The sensitivity and specificity were 100% and 90.3%, respectively. AUROC for the diagnosis of SOS/VOD was 0.973 (0.943-1.000) for LS increase ≥  + 12.6 kPa from baseline after HSCT. The change of ≥  + 12.6 kPa from baseline was observed in all 14 patients in the SOS/VOD group (100%) and in four patients in the non-SOS/VOD group (5.6%). The sensitivity and specificity were 100% and 94.4%, respectively.

CONCLUSION

LSM using TE may contribute to establishing the diagnosis of SOS/VOD after HSCT.

Hepatic veno-occlusive disease complicated with extreme hyperammonaemia (920 µmol/L) treated with defibrotide, lactulose, rifampin and haemodialysis

Hepatic veno-occlusive disease (VOD)/sinusoidal obstructive syndrome (SOS) is a severe complication that can occur following haematopoietic stem cell transplant (HSCT) with high-intensity conditioning chemotherapy regimens. Severe VOD/SOS, often characterised by multiorgan failure, is associated with a high mortality rate. This case report details the complex clinical course of a male patient in his mid-20s, recently diagnosed with B cell acute lymphoblastic leukaemia, who underwent allogeneic HSCT. Based on the 2023 European Society for Blood and Marrow Transplantation (EBMT) criteria, the patient developed very severe VOD/SOS, prompting immediate treatment with defibrotide. Unexpectedly, he developed profound hyperammonaemia exceeding 900 µmol/L, leading to encephalopathy and cerebral oedema. Despite aggressive interventions including defibrotide, lactulose, rifampin and haemodialysis, the patient passed away due to cerebral oedema and pulseless electrical activity arrest. We theorise the hyperammonaemia is disproportionate to his hepatic dysfunction and is possibly secondary to an acquired defect of the urea synthesis consistent with idiopathic hyperammonaemia, a rare complication in patients receiving intense conditioning chemotherapy.

Incidence and risk factors of early onset VOD/SOS differ in younger vs older adults after stem cell transplantation

ABSTRACT

Veno-occlusive disease (VOD) is a rare but potentially life-threatening complication after allogeneic hematopoietic stem cell transplantation (allo-SCT). Although increasing awareness and modern transplant techniques have mitigated risk, the interaction of historic risk factors in the current era with posttransplant cyclophosphamide (PTCy) is unknown. We performed a retrospective single-center analysis of adult patients aged ≥18 years undergoing allo-SCT (N = 1561) using predominately PTCy as graft-versus-host disease (GVHD) prophylaxis (72%). We found a higher rate of VOD at 16.8% (20 of 119) in those aged ≤25 years compared with 3.8% (55 of 1442) in those aged >25 years, with unique predictors of VOD within each cohort. Multivariate classification and regression tree (CART) analysis confirmed age as the primary independent determinant of the rate of VOD. Among patients aged 18 to 25 years, disease risk index (DRI; 31% with high/very high DRI vs 12% low/intermediate DRI; P = .03) and prior lines of chemotherapy (24% with >1 vs 6% with ≤1; P = .03) were the strongest predictors of VOD. Incidence of VOD in patients aged >25 years of age consistently ranged between 3% and 5% across most risk factors evaluated, with only hepatic factors (baseline elevation of bilirubin, aspartate transferase, alanine aminotransferase) or gemtuzumab exposure associated with increased rates of VOD. There was no significant difference in rates of VOD in those receiving PTCy compared with those receiving alternate GVHD prophylaxis. Our data highlight the differences in incidence and predictors of VOD between younger (≤25) and older (>25) adults undergoing allo-SCT.

Imaging of abdominopelvic oncologic emergencies

With advancements in cancer treatment, the survival rates for many malignancies have increased. However, both the primary tumors and the treatments themselves can give rise to various complications. Acute symptoms in oncology patients require prompt attention. Abdominopelvic oncologic emergencies can be classified into four distinct categories: vascular, bowel, hepatopancreatobiliary, and bone-related complications. Radiologists need to be familiar with these complications to ensure timely diagnosis, which ultimately enhances patient outcomes.

Cord Blood Transplantation for Very Early-Onset Inflammatory Bowel Disease Caused by Interleukin-10 Receptor Deficiency

PURPOSE

Interleukin-10 receptor (IL-10R) deficiency can result in life-threatening very early-onset inflammatory bowel disease (VEO-IBD). Umbilical cord blood transplantation (UCBT) is a curative therapy for patients with IL-10R deficiency. This study aimed to investigate the efficacy of UCBT in treating IL-10R deficiency and develop a predictive model based on pre-transplant factors.

METHODS

Eighty patients with IL-10R deficiency who underwent UCBT between July 2015 and April 2023 were retrospectively analyzed. Cox proportional hazards regression and random survival forest were used to develop a predictive model.

RESULTS

Median age at transplant was 13.0 months (interquartile range [IQR], 8.8-25.3 months). With a median follow-up time of 29.4 months (IQR, 3.2-57.1 months), the overall survival (OS) rate was 65.0% (95% confidence interval [CI], 55.3%-76.3%). The engraftment rate was 85% (95% CI, 77%-93%). The cumulative incidences of acute and chronic graft-versus-host disease were 48.2% (95% CI, 37.1%-59.4%) and 12.2% (95% CI, 4.7%-19.8%), respectively. VEO-IBD-associated clinical symptoms were resolved in all survivors. The multivariate analysis showed that IL-6 and stool occult blood were independent prognostic risk factors. The multivariate Cox proportional hazards regression model with stool occult blood, length- or height-for-age Z-score, medical history of sepsis, and cord blood total nucleated cells showed good discrimination ability, with a bootstrap concordance index of 0.767-0.775 in predicting OS.

CONCLUSION

Better inflammation control before transplantation and higher cord blood total nucleated cell levels can improve patient prognosis. The nomogram can successfully predict OS in patients with IL-10R deficiency undergoing UCBT.

Primary Budd-Chiari syndrome versus sinusoidal obstruction syndrome: a review

Budd-Chiari syndrome (BCS) and sinusoidal obstruction syndrome (SOS) are two major vascular disorders of the liver, of which both can cause portal hypertension related complications, but their locations of obstruction are different. BCS refers to the obstruction from the hepatic vein to the junction between the inferior vena cava and right atrium, which is the major etiology of post-sinusoidal portal hypertension; by comparison, SOS is characterized as the obstruction at the level of hepatic sinusoids and terminal venulae, which is a cause of sinusoidal portal hypertension. Both of them can cause hepatic congestion with life-threatening complications, especially acute liver failure and chronic portal hypertension, and share some similar features in terms of imaging and clinical presentations, but they have heterogeneous risk factors, management strategy, and prognosis. Herein, this paper reviews the current evidence and then summarizes the difference between primary BCS and SOS in terms of risk factors, clinical features, diagnosis, and treatment.

Acute GVHD classification based on the dynamics of GVHD skin involvement from its appearance to the start of systemic treatment

We conducted a prospective study aimed at investigating the prognostic value of the dynamic of a-GVHD progression from cutaneous to visceral involvement. In 108 consecutive patients who underwent allogeneic HSCT, we classified a-GVHD according to a "GHVD skin dynamic": 18/82 patients started Corticosteroid (CS) within 48 h (Group 1); 13/82 started CS within days 3-7 (Group 2); Group 3A (n 31) was defined when Skin GVHD Overall Grade 1, left untreated for 1 week, showed an increase in involved body surface area <5 %; Group 3B (n 20), was defined when Skin GVHD Overall Grade 1, left untreated at 1 week, had an increase in involved body surface area >5%. These four groups had distinctive 2-y OS. Patients could be then grouped into "poor risk" (Group 1 and Group 3B) and "good risk" (Group 2 and Group 3A). "Poor risk" had inferior OS in univariate and multivariate analysis, (HR 2.222; 95% CL: 1.017-4.855; p 0.04). Among the patients with skin-only Grade 1 GVHD, subgroup 3A had an OS of 75.1% versus 39.8% found in subgroup 3B (p = 0.03). The dynamic of skin GVHD may be used to classify a-GVHD and guide treatment in Overall Grade 1 skin-only GVHD.

Andrographolide attenuated MCT-induced HSOS via regulating NRF2-initiated mitochondrial biogenesis and antioxidant response

Hepatic sinusoidal obstruction syndrome (HSOS) is a death-dealing liver disease with a fatality rate of up to 67%. In the study present, we explored the efficacy of andrographolide (Andro), a diterpene lactone from Andrographis Herba, in ameliorating the monocrotaline (MCT)-induced HSOS and the underlying mechanism. The alleviation of Andro on MCT-induced rats HSOS was proved by biochemical index detection, electron microscope observation, and liver histological evaluation. Detection of hepatic ATP content, mitochondrial DNA (mtDNA) copy number, and protein expression of nuclear respiratory factor-1 (NRF1) and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) demonstrated that Andro strengthened mitochondrial biogenesis in livers from MCT-treated rats. Chromatin immunoprecipitation assay exhibited that Andro enhanced the occupation of nuclear factor erythroid 2-related factor 2 (NFE2L2, also known as NRF2) in the promoter regions of both PPARGC1A and NRF1. Andro also activated the NRF2-dependent anti-oxidative response and alleviated liver oxidative injury. In Nrf2 knock-out mice, MCT induced more severe liver damage, and Andro showed no alleviation in it. Furthermore, the Andro-activated mitochondrial biogenesis and anti-oxidative response were reduced in Nrf2 knock-out mice. Contrastingly, knocking out Kelch-like ECH-associated protein 1 (Keap1), a NRF2 repressor, reduced MCT-induced liver damage. Results from co-immunoprecipitation, molecular docking analysis, biotin-Andro pull-down, cellular thermal shift assay, and surface plasmon resonance assay showed that Andro hindered the NRF2-KEAP1 interaction via directly binding to KEAP1. In conclusion, our results revealed that NRF2-dependent liver mitochondrial biogenesis and anti-oxidative response were essential for the Andro-provided alleviation of the MCT-induced HSOS. Graphical Headlights: 1. Andro alleviated MCT-induced HSOS via activating antioxidative response and promoting mitochondrial biogenesis. 2. Andro-activated antioxidative response and mitochondrial biogenesis were NRF2-dependent. 3. Andro activated NRF2 via binding to KEAP1.

Diagnosis and management of endothelial disorders following haematopoietic stem cell transplantation

Haematopoietic stem cell transplantation is a mainstay of therapy for numerous malignant and nonmalignant diseases. Endothelial activation and dysfunction occur after stem cell transplantation, driven by various patient- and transplant-specific factors. This can manifest as one of the relatively uncommon endothelial injury syndromes, such as sinusoidal obstruction syndrome, transplant-associated thrombotic microangiopathy, idiopathic pneumonia syndrome, capillary leak syndrome, engraftment syndrome or posterior reversible encephalopathy syndrome. This review focuses on the pathogenesis, classification and diagnosis of these disorders, as well as provides guidance on risk mitigation and treatment.

Antisense oligonucleotides: a novel Frontier in pharmacological strategy

Antisense oligonucleotides (ASOs) are short single stranded synthetic RNA or DNA molecules, whereas double-stranded RNA nucleotide sequences are called small interfering RNA (siRNA). ASOs bind to complementary nucleic acid sequences impacting the associated functions of the targeted nucleic acids. They represent an emerging class of drugs that, through a revolutionary mechanism of action, aim to directly regulate disease-causing genes and their variants, providing an alternative tool to traditional "protein-specific" therapies. The majority of the ASOs are designed to treat orphan genetic disorders that in most of the cases are seriously disabling and still lacking an adequate therapy. In order to translate ASOs into clinical success, constant technological advances have been instrumental in overcoming several pharmacological, toxicological and formulation limitations. Accordingly, chemical structures have been recently implemented and new bio-conjugation and nanocarriers formulation strategies explored. The aim of this work is to offer an overview of the antisense technology with a comparative analysis of the oligonucleotides approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA).

Metformin pretreatment ameliorates busulfan-induced liver endothelial toxicity during haematopoietic stem cell transplantation

The success of Haematopoietic cell transplantation (HCT) is often limited by regimen-related toxicity (RRT) caused by conditioning regimen drugs. Among different conditioning drugs, busulfan (Bu) and treosulfan (Treo), although widely used in HCT, exhibit different toxicity profiles, the mechanism of which is still unclear. Here we investigated the effects of Bu and Treo in endothelial cells. While both Bu and Treo induced DNA damage in endothelial cells, we observed Bu alone to induce oxidative stress and sustained activation of phospho-ERK1/2, leading to apoptosis. However, Treo-treated cells exhibited no oxidative stress/apoptosis of endothelial cells. Screening of pharmacological inhibitors of both ROS and p-ERK revealed that metformin effectively ameliorates Bu-mediated toxicity in endothelial cells. In Balb/c mice, we observed a significant reduction in bone marrow endothelial cells in Bu-treated mice compared to Treo-treated mice. Further, liver sinusoidal endothelial cells (LSEC) was damaged by Bu, which is implicated in liver vasculature and their functional capacity to uptake FITC-albumin. However, Treo-treated mice liver vasculature was morphologically and functionally normal. When mice were pretreated with metformin followed by Bu, LSECs damage was ameliorated morphologically and functionally. Bone marrow transplants done on these mice did not affect the engraftment of donor cells.

Constructing training set using distance between learnt graphical models of time series data on patient physiology, to predict disease scores

Interventional endeavours in medicine include prediction of a score that parametrises a new subject's susceptibility to a given disease, at the pre-onset stage. Here, for the first time, we provide reliable learning of such a score in the context of the potentially-terminal disease VOD, that often arises after bone marrow transplants. Indeed, the probability of surviving VOD, is correlated with early intervention. In our work, the VOD-score of each patient in a retrospective cohort, is defined as the distance between the (posterior) probability of a random graph variable-given the inter-variable partial correlation matrix of the time series data on variables that represent different aspects of patient physiology-and that given such time series data of an arbitrarily-selected reference patient. Such time series data is recorded from a pre-transplant to a post-transplant time, for each patient in this cohort, though the data available for distinct patients bear differential temporal coverage, owing to differential patient longevities. Each graph is a Soft Random Geometric Graph drawn in a probabilistic metric space, and the computed inter-graph distance is oblivious to the length of the time series data. The VOD-score learnt in this way, and the corresponding pre-transplant parameter vector of each patient in this retrospective cohort, then results in the training data, using which we learn the function that takes VOD-score as its input, and outputs the vector of pre-transplant parameters. We model this function with a vector-variate Gaussian Process, the covariance structure of which is kernel parametrised. Such modelling is easier than if the score variable were the output. Then for any prospective patient, whose pre-transplant variables are known, we learn the VOD-score (and the hyperparameters of the covariance kernel), using Markov Chain Monte Carlo based inference.

Acquired Isolated Factor VII Deficiency in Plasma Cell Dyscrasias: A Brief Presentation of Two Plasma-Cell-Leukemia-Related Cases and Review of Literature

Acquired isolated factor VII (FVII) deficiency is a rare but important discovery in patients with plasma cell disorders with significant therapeutic and prognostic implications. The present analysis and review of cases reported in the literature is intended to highlight disease-related characteristics associated with this rare clotting defect, clinical manifestations and outcome, and potential underlying mechanisms, and to provide guidance on how to manage these patients in terms of prophylactic and therapeutic measures. The discovery of acquired FVII deficiency in a patient with multiple myeloma (MM) or monoclonal gammopathy of uncertain significance (MGUS) should prompt an evaluation for AL amyloidosis, particularly for amyloid hepatosplenic involvement, whenever not previously documented. Acquired FVII deficiency in patients with MM and AL amyloidosis is frequently associated with severe bleeding diathesis, also related to a number of concomitant predisposing factors, adversely affecting the outcome. The prompt institution of a rapidly acting therapy is crucial to prevent severe bleeding complications and positively impact outcome. Recombinant activated factor VII (rVIIa) may represent a useful supportive care measure, both in treating active bleeding and in the peri-procedural setting. However, further clinical experience is needed to optimize the therapeutic management of this rare disorder.

Liver Pathology After Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation is used to treat a variety of hematologic malignancies and autoimmune conditions. The immunosuppressive medications as well as other therapies used both before and after transplantation leave patients susceptible to a wide spectrum of complications, including liver injury. Causes for liver damage associated with stem cell transplantation include sinusoidal obstruction syndrome, graft-versus-host disease, iron overload, and opportunistic infection. Here, the authors review the clinical and pathological findings of these etiologies of liver injury and provide a framework for diagnosis.

Melatonin attenuates monocrotaline-induced hepatic sinusoidal obstruction syndrome in rats via activation of Sirtuin-3

Melatonin possesses potent hepatoprotective properties, but it remains to be elucidated whether melatonin has a therapeutic effect on monocrotaline (MCT)-induced hepatic sinusoidal obstruction syndrome (HSOS). In this study, male Sprague Dawley rats were intraperitoneally injected with melatonin or the same volume of vehicle at 0 and 24 h after MCT intragastric administration. Next, hematoxylin-eosin staining and electron microscopy were performed to evaluate the hepatic sinusoidal injury of rats. Endothelial cell marker RECA-1 was observed by immunohistochemistry. Hepatic oxidative stress was analyzed by detecting malondialdehyde, glutathione S-transferase, and reactive oxygen species. Assessment of liver function was carried out by analysis of serum aspartate aminotransferase, alanine aminotransferase, total bilirubin, and albumin levels. Real-time polymerase chain reaction and Western blot analysis were used to identify liver Sirtuin-3 (SIRT3) and active matrix metallopeptidase 9 (MMP-9) expression. Besides, liver sinusoidal endothelial cells (LSECs) were used for the in vitro functional verification experiment. Specifically, liver histology of the melatonin-treated groups showed that the pathological damages caused by MCT were significantly attenuated, total HSOS scores were decreased, and the elevation of serum hyaluronic acid observed in the model group was also reduced. Moreover, melatonin treatment also improved the survival of rats after partial hepatectomy. Administration of melatonin ameliorated MCT-induced LSECs injury, hepatic oxidative stress, and hepatic dysfunction. Furthermore, melatonin treatment increased SIRT3 expression while attenuating MMP-9 activity in liver tissues. Cell experiment also demonstrated that SIRT3 might mediate the protective effect of melatonin on LSECs. Collectively, our study provided the potential rationale for the application of melatonin for the prevention of MCT-induced HSOS.

Idiopathic hypereosinophilic syndrome with hepatic sinusoidal obstruction syndrome: A case report and literature review

BACKGROUND

Hypereosinophilic syndrome (HES) is classified as primary, secondary or idiopathic. Idiopathic HES (IHES) has a variable clinical presentation and may involve multiple organs causing severe damage. Hepatic sinusoidal obstruction syndrome (HSOS) is characterized by damage to the endothelial cells of the hepatic sinusoids of the hepatic venules, with occlusion of the hepatic venules, and hepatocyte necrosis. We report a case of IHES with HSOS of uncertain etiology.

CASE SUMMARY

A 70-year-old male patient was admitted to our hospital with pruritus and a rash on the extremities for > 5 mo. He had previously undergone antiallergic treatment and herbal therapy in the local hospital, but the symptoms recurred. Relevant examinations were completed after admission. Bone marrow aspiration biopsy showed a significantly higher percentage of eosinophils (23%) with approximately normal morphology. Ultrasound-guided hepatic aspiration biopsy indicated HSOS. Contrast-enhanced computed tomography (CT) of the upper abdomen showed hepatic venule congestion with hydrothorax and ascites. The patient was initially diagnosed with IHES and hepatic venule occlusion. Prednisone, low molecular weight heparin and ursodeoxycholic acid were given for treatment, followed by discontinuation of low molecular weight heparin due to ecchymosis. Routine blood tests, biochemical tests, and imaging such as enhanced CT of the upper abdomen and pelvis were reviewed regularly.

CONCLUSION

Hypereosinophilia may play a facilitating role in the occurrence and development of HSOS.

Sinusoidal obstruction syndrome associated with disseminated toxoplasmosis involving the liver after allogeneic hematopoietic stem cell transplantation: A case report

Sinusoidal obstruction syndrome (SOS) is a fatal complication after hematopoietic stem cell transplantation (HSCT). Only a few complications after HSCT have been reported as risk factors for SOS, including sepsis. Here, we report the case of a 35-year-old male diagnosed with Philadelphia chromosome-positive acute lymphoblastic leukemia who underwent peripheral blood HSCT from a human leukocyte antigen-matched unrelated female donor in remission. Graft-versus-host disease prophylaxis contained tacrolimus, methotrexate, and low-dose anti-thymoglobulin. The patient was treated with methylprednisolone for engraftment syndrome from day 22. On day 53, he presented worsening fatigue, breathlessness, and abdominal pain in the right upper quadrant that had persisted for 4 days. Laboratory tests showed severe inflammation, liver dysfunction, and positive for Toxoplasma gondii PCR. He died on day 55. An autopsy showed SOS and disseminated toxoplasmosis. Hepatic infection with T. gondii was identified in zone 3 of the liver, which overlapped with the pathological features of SOS. In addition, the timing of the exacerbation of hepatic dysfunction coincided with the onset of systemic inflammatory symptoms and T. gondii reactivation. This rare case of toxoplasmosis is the first to suggest that hepatic infection with T. gondii is strongly associated with SOS after HSCT.

Hypofibrinolysis in pediatric patients with veno-occlusive disease in hematopoietic stem cell transplantation

PURPOSE

Veno-occlusive disease (VOD) is a serious complication of hematopoietic stem cell transplantation (HSCT) with a high incidence in pediatric patients. This study aimed to detect signs of hypofibrinolysis using thrombelastography.

METHODS

In this prospective single-center study, thrombelastographic measurements (EX and TPA tests) were taken during HSCT to detect signs of impaired coagulation, clot formation, or hypofibrinolysis.

RESULTS

Of 51 patients undergoing allogeneic and autologous HSCT, five (9.8%) developed VOD and received defibrotide treatment. Thrombelastography measurements were also obtained from 55 healthy children as a control group. The results show that clot lysis was prolonged in VOD patients compared to other HSCT patients and control group (lysis time, TPA test: day + 14 to + 21: VOD: 330 ± 67 s vs. HSCT: 246 ± 53 s; p = 0.0106; control: 234 ± 50 s; control vs. VOD: p = 0.0299). The maximum lysis was reduced in HSCT patients compared to controls (EX test: control: 8.3 ± 3.2%; HSCT: day 0 to + 6: 5.3 ± 2.6%, p < 0.0001; day + 7 to + 13: 3.9 ± 2.1%, p < 0.0001; day + 14 to d + 21: 4.1 ± 2.3%, p < 0.0001).

CONCLUSION

These results suggest that HSCT patients exhibit reduced fibrinolytic capacities and patients diagnosed with VOD show signs of hypofibrinolysis. This prospective study shows that fibrinolysis can be assessed in a rapid and accessible way via thrombelastography. Thrombelastography might be a parameter to support the diagnosis of a VOD and to serve as a follow-up parameter after the diagnosis of a VOD.

Incidence of sinusoidal obstruction syndrome/veno-occlusive disease and treatment with defibrotide in allogeneic transplant: A multicentre Australasian registry study

BACKGROUND

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is an established complication in patients undergoing allogeneic haemopoietic stem cell transplantation. Defibrotide is an effective and safe pharmacological option for treating diagnosed SOS/VOD.

OBJECTIVE

By exploring data provided to the Australasian Bone Marrow Transplant Recipient Registry (ABMTRR) by centres from Australia and New Zealand, this study aimed to describe the incidence of SOS/VOD and patterns of defibrotide use from 2016 to 2020.

STUDY DESIGN

Patients who underwent allogeneic HSCT between 2016 and 2020 were identified from the ABMTRR. Data was extracted for a total of 3346 patients, 2692 from adult centres and 654 from paediatric centres, with a median follow up of 21.5 months and 33.3 months respectively. Descriptive statistics were used to describe the patient population, including the incidence of SOS/VOD and defibrotide use. Comparisons were made between patients not experiencing SOS/VOD, and those with the diagnosis, divided into defibrotide and no-defibrotide cohorts. Associations with overall survival and day 100 survival with variables such as gender, age, disease at transplant, source of stem cells, conditioning agents, SOS/VOD diagnosis and use of defibrotide were determined.

RESULTS

The reported incidence of SOS/VOD was 4.1% in adult centres and 11.5% in paediatric centres. Defibrotide was administered to 74.8% of adult patients with SOS/VOD and 97.3% of paediatric patients. Significant variability of use, dose and duration of defibrotide was seen across the adult centres. Day 100 survival rate and median overall survival (OS) for patients managed with defibrotide was 51.8% and 103 days respectively for adult patients, and 90.4% and not reached for paediatric patients. In adults, older age at transplant, an HLA matched donor who was a non-sibling relative, and a diagnosis of SOS/VOD treated with defibrotide, were all associated with reduced OS. In paediatrics, the patient and transplant characteristics that were associated with a reduced OS were a diagnosis of SOS/VOD and donor relation as 2 or more HLA mismatched relative.

CONCLUSION

A collaborative approach across Australasia to diagnose and manage SOS/VOD, in particular with respect to consistent defibrotide use, is recommended.

Predictive factors of collateral vessel development induced by oxaliplatin-based chemotherapy

BACKGROUND AND AIM

Oxaliplatin can lead to hepatic sinusoidal injury, called hepatic sinusoidal obstruction syndrome (SOS), resulting in portal hypertension-related complications. This could worsen the clinical course of the patients treated with oxaliplatin. Early diagnosis is challenging. We explored predictive markers of oxaliplatin-induced collateral vessels.

METHODS

Patients who received oxaliplatin-based chemotherapy were retrospectively screened. We evaluated their laboratory findings and spleen size on computed tomography immediately before oxaliplatin-based chemotherapy and after 6 months of treatment. The primary outcome was collateral vessel development, as a surrogate marker for oxaliplatin-induced SOS in patients who underwent oxaliplatin-based chemotherapy. The secondary outcome was the identification of factors that predicted the development of collateral vessels.

RESULTS

We enrolled 161 patients who received oxaliplatin-based chemotherapy. They had a median age of 69 years, and 63.3% were men. Collateral vessels developed in nine (5.6%) patients during the study period. After oxaliplatin-based chemotherapy, the spleen size increased in 104 patients (64.6%), with a ≥ 30% increase in 19.4% of the patients. Univariate analysis showed that the Fibrosis-4 (FIB-4) index (≥ 1.76; OR 9.17), aspartate aminotransferase:platelet ratio index (APRI) (≥ 0.193; OR 9.62), cumulative dose of oxaliplatin (≥ 1000 mg; OR 8.43), and increase in spleen size (≥ 30%; OR 6.01) were significant risk factors for collateral vessel development. Multivariate analysis after stepwise selection revealed that the FIB-4 index and spleen size were significant independent predictive factors.

CONCLUSION

A ≥ 1.76 increase in the FIB-4 index and a ≥ 30% increase in spleen size after 6 months of oxaliplatin-based chemotherapy were significant predictive markers for collateral vessel development.

Hepatobiliary disease after bone marrow transplant

INTRODUCTION

Bone marrow transplantation (BMT) is the standard treatment for several hematologic pathologies. Post-BMT patients may develop hepatobiliary complications that impact morbidity and mortality. The differential diagnosis may include drug-induced liver injury (DILI), sepsis-associated liver injury (SALI), sinusoidal obstruction syndrome (SOS), graft-versus-host disease (GVHD), viral hepatitis, ischemic and fulminant hepatitis, among others.

AREA COVERED

Defining the etiology of hepatobiliary injury is challenging due to the overlapping symptoms. Thus, it is necessary to be aware of and understand the clinical characteristics of these hepatobiliary complications and provide adequate management with possible better outcomes. We reviewed the scientific literature focused on early hepatobiliary complications associated with BMT. We searched the PubMed database using the following descriptors: hepatic complications, drug-induced liver disease, graft-versus-host disease, cholestasis, sepsis, sinusoidal obstruction syndrome, cytomegalovirus, viral hepatitis, bone marrow transplantation, and hematopoietic stem cell transplantation.

EXPERT OPINION

Post-BMT hepatobiliary complications comprise several differential diagnoses and are challenges for the hepatologist's clinical practice. When evaluating these patients, it is necessary to consider the temporality between the use of certain medications, the increase in liver enzymes, and the presence of infection, in addition to applying diagnostic criteria and complementary tests for a specific diagnosis.

Endothelial Dysfunction Syndromes after Allogeneic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the only therapy with a curative potential for a variety of malignant and non-malignant diseases. The major limitation of the procedure is the significant morbidity and mortality mainly associated with the development of graft versus host disease (GVHD) as well as with a series of complications related to endothelial injury, such as sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), transplant-associated thrombotic microangiopathy (TA-TMA), etc. Endothelial cells (ECs) are key players in the maintenance of vascular homeostasis and during allo-HSCT are confronted by multiple challenges, such as the toxicity from conditioning, the administration of calcineurin inhibitors, the immunosuppression associated infections, and the donor alloreactivity against host tissues. The early diagnosis of endothelial dysfunction syndromes is of paramount importance for the development of effective prophylactic and therapeutic strategies. There is an urgent need for the better understanding of the pathogenetic mechanisms as well as for the identification of novel biomarkers for the early diagnosis of endothelial damage. This review summarizes the current knowledge on the biology of the endothelial dysfunction syndromes after allo-HSCT, along with the respective therapeutic approaches, and discusses the strengths and weaknesses of possible biomarkers of endothelial damage and dysfunction.

Post-Transplantation Sinusoidal Obstruction Syndrome in Adult Patients with B Cell Acute Lymphoblastic Leukemia Treated with Pretransplantation Inotuzumab

Sinusoidal obstruction syndrome (SOS) is a potentially life-threatening complication that can be observed after allogeneic hematopoietic cell transplantation (HCT). Inotuzumab ozogamicin is an anti-CD22 monoclonal antibody-drug conjugate that has demonstrated high efficacy in relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) but is associated with an increased risk of SOS in HCT recipients. Here we aimed to examine the incidence and outcomes of SOS in 47 adult patients with R/R ALL who received inotuzumab therapy and subsequently underwent HCT at our institution. All patients received prophylactic therapy with ursodiol, and continuous low-dose heparin also was administered to patients receiving myeloablative conditioning (MAC). SOS occurred in 12 patients (26%) post-HCT, at a median onset of 11 days (range, 3 to 41 days). SOS was graded as very severe in 50% (n = 6), severe in 25% (n = 3), and mild in 25% (n = 3). All patients diagnosed with SOS received treatment with defibrotide for a median of 21 days (range, 3 to 34 days), with resolution of SOS occurring in 8 patients (67%). Mortality from SOS was 33% (n = 4) and occurred at a median of 10 days from diagnosis (range, 3 to 31 days) in patients graded as very severe (n = 3) or severe (n = 1). There were no significant differences between patients who developed SOS and those who did not develop SOS in the median time from the last dose of inotuzumab to transplantation (46 days versus 53 days; P = .37), use of an MAC regimen (42% versus 49%; P = .75), number of lines of therapy prior to inotuzumab (P = .79), median number of administered cycles of inotuzumab (2 versus 2; P = .14), or receipt of inotuzumab as the last therapy prior to HCT (67% versus 66%; P = 1.0). Sirolimus-based graft-versus-host disease (GVHD) prophylaxis was used more frequently in the SOS group (75% versus 29%; P < .01), but there was no between-group difference in the peak sirolimus level (P = .81) or the median time to peak sirolimus level (7 days versus 3.5 days; P = .39). In univariable analysis, only the use of sirolimus-based GVHD prophylaxis was significantly associated with an increased risk of SOS (hazard ratio [HR], 7.50; 95% confidence interval [CI], 1.7 to 33.6; P < .01). In the SOS group, the 100-day mortality rate was 33% (n = 4), and median overall survival (OS) post-HCT was 4.3 months (range, 0.2 to 57.2 months). In the group without SOS, the 100-day mortality rate was 14% (n = 5) and the median OS post-HCT was 10.7 months (range, .52 to 39.6 months). In this study cohort, SOS was prevalent in HCT recipients who had been treated with inotuzumab prior to transplantation, and sirolimus-based GVHD prophylaxis was a risk factor for SOS in inotuzumab recipients.

Efficacy and Safety of Recombinant Thrombomodulin for the Prophylaxis of Veno-Occlusive Complication in Allogeneiccit Hematopoietic Stem Cell Transplantation: A Systematic Review and Meta-Analysis

BACKGROUND

Hepatic veno-occlusive disease (VOD), also termed as sinusoidal obstruction syndrome (SOS), is a lethal complication after hematopoietic stem cell transplantation (HSCT). Various factors put patients undergoing allogeneic HSCT at an increased risk for VOD. Thrombomodulin (TM) is an important factor which has a wide range of effects, including anticoagulant, anti-inflammatory, angiogenic, and protective effect, on endothelial cells. It plays a role in preventing excessive coagulation and thrombosis by binding with thrombin and inhibiting the coagulation cascade. There are a limited number of options for the prevention of this fatal complication. Recombinant thrombomodulin (rTM), an endothelial anticoagulant co-factor, as prophylactic therapy might be able to prevent veno-occlusive complications after stem cell transplantation.

METHODS

A literature search was performed on PubMed, Embase, and Web of Science. We used the following Mesh terms and Emtree terms, "Hepatic Veno-Occlusive Diseases" OR "Sinusoidal Obstruction" OR "Stem Cell Transplantations " AND "Thrombomodulin" from the inception of data up to April 1, 2021. The PICO (Patient/Population, Intervention, Comparison and Outcomes) framework was used for the literature search.

RESULTS

For the VOD incidence after HSCTstem cell transplantation, the result was in favor of rTM with a risk ratio (RR) of 0.53 (I² = 0%, 95% confidence interval [CI] = 0.32-0.89). The incidence of transplant-associated thrombotic microangiopathy (TA-TMA) after HSCT was reduced in rTM group. The RR for incidence of TA-TMA was 0.48 (I² = 62%, 95% CI = 0.20-1.17) favoring rTM. The RR for incidence of graft-versus-host disease (GvHD) was also lower in rTM group, 0.48 (I² = 64%, 95% CI = 0.32-0.72).

CONCLUSION

In our meta-analysis, we evaluate the efficacy and safety of rTM in the prevention of SOS after HSCT. According to our results, rTM use led to a significant reduction in SOS episodes, TA-TMA, and GvHD after HSCT.

Association of crystalloid fluid infusion with intravascular hemolysis and organ dysfunction in hematopoietic stem cell transplant patients

Endothelial cell activation and injury is common after hematopoietic stem cell transplant (HSCT) and is associated with many post-transplant complications. An underexplored mechanism of endothelial cell damage in this population is the infusion of normal saline (NS, 0.9 % sodium chloride) and other crystalloids, as NS use is associated with adverse outcomes in other patient populations. We hypothesized that the infusion of unbalanced crystalloids during HSCT may lead to changes in biomarkers commonly associated with red blood cell (RBC) hemolysis in patients before and after infusion, and that markers of endothelial and end-organ damage during admission may be associated with markers of hemolysis and total crystalloid use. Samples were collected from 97 patients. From pre-fluid infusion to post-fluid infusion, mean haptoglobin decreased (11.7 ug/ml vs 8.4 ug/ml; p < 0.0001), hemopexin decreased (549 vs 512 μg/ml; p = 0.005), and red cell distribution width (RDW) decreased (15.7 vs 15.6; p = 0.0009). During admission (mean 19.4 days, SD 9.9), all markers of tissue and organ damage, including mean creatinine, lactate dehydrogenase (LDH), blood urea nitrogen (BUN), total bilirubin, AST, and ALT, increased from admission to peak levels (p < 0.0001). On linear regression, fluid volume (ml/kg) of crystalloid infusion positively predicted post-fluid infusion cell-free hemoglobin (r(96) = 0.34, p < 0.0001), free heme (r(96) = 0.36, p < 0.0001), and peak LDH during admission (r(75) = 0.23, p = 0.041), and negatively predicted post-fluid infusion hemopexin (r(96) = - 0.34, p < 0.0001). Unbalanced crystalloids may contribute to hemolysis and endothelial damage in HSCT patients. Alternatives such as buffered crystalloid solutions (PlasmaLyte, Lactated Ringer's) may be worth investigating in this population.

Busulfan, Melphalan, and Etoposide (BuME) Showed an Equivalent Effect to Busulfan, Cyclophosphamide, and Etoposide (BuCE) as Conditioning Therapy for Autologous Stem Cell Transplantation in Patients with Relapsed or High-Risk Non-Hodgkin's Lymphoma: A Multicenter Randomized Phase II Study bythe Consortium for Improving Survival of Lymphoma (CISL)

PURPOSE

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is the standard management for relapsed or high-risk non-Hodgkin's lymphoma (NHL). We reported the busulfan, melphalan, and etoposide (BuME) conditioning regimen was effective in patients with relapsed or high-risk NHL. Moreover, the busulfan, cyclophosphamide, and etoposide (BuCE) conditioning regimen has been used widely in ASCT for NHL. Therefore, based on these encouraging results, this randomized phase II multicenter trial compared the outcomes of BuME and BuCE as conditioning therapies for ASCT in patients with NHL.

MATERIALS AND METHODS

Patients were randomly assigned to receive either BuME (n=36) or BuCE (n=39). The BuME regimen was comprised of busulfan (3.2 mg/kg/day, intravenously) administered on days -7, -6, and -5, etoposide (400 mg/m2 intravenously) on days -5 and -4, and melphalan (50 mg/m2/day intravenously) on days -3 and -2. The BuCE regimen was comprised of busulfan (3.2 mg/kg/day intravenously) on days -7, -6, and -5, etoposide (400 mg/m2/day intravenously) on days -5 and -4, and cyclophosphamide (50 mg/kg/day intravenously) on days -3 and -2. The primary endpoint was 2-year progression-free survival (PFS).

RESULTS

Seventy-five patients were enrolled. Eleven patients (30.5%) in the BuME group and 13 patients (33.3%) in the BuCE group had disease progression or died. The 2-year PFS rate was 65.4% in the BuME group and 60.6% in the BuCE group (p=0.746). There were no non-relapse mortalities within 100 days after transplantation.

CONCLUSION

There were no significant differences in PFS between the two groups. Therefore, busulfan-based conditioning regimens, BuME and BuCE, may be important treatment substitutes for the BCNU-containing regimens.

Low Plasma Levels of Hyaluronic Acid Might Rule Out Sinusoidal Obstruction Syndrome after Hematopoietic Stem Cell Transplantation

Background

Sinusoidal obstructive syndrome (SOS) is a potentially fatal complication secondary to hematopoietic stem cell transplant (HSCT) conditioning. Endothelial damage plasma biomarkers such as plasminogen activator inhibitor-1 (PAI-1), hyaluronic acid (HA), and vascular adhesion molecule-1 (VCAM1) represent potential diagnostic tools for SOS.

Methods

We prospectively collected serial citrated blood samples (baseline, day 0, day 7, and day 14) in all adult patients undergoing HSCT at La Paz Hospital, Madrid. Samples were later analyzed by ELISA (enzyme-linked immunosorbent assay) for HA, VCAM1, and PAI-1 concentrations.

Results

During sixteen months, we prospectively recruited 47 patients. Seven patients (14%) were diagnosed with SOS according to the EBMT criteria for SOS/VOD diagnosis and received treatment with defibrotide. Our study showed a statistically significant elevation of HA on day 7 in SOS patients, preceding clinical SOS diagnosis, with a sensitivity of 100%. Furthermore, we observed a significant increase of HA and VCAM1 levels on day 14. Regarding risk factors, we observed a statistically significant association between SOS diagnosis and the fact that patients received 3 or more previous lines of treatment before HSCT.

Conclusions

The early significant increase in HA levels observed opens the door to a noninvasive peripheral blood test which could have the potential to improve diagnosis and facilitate prophylactic and therapeutic management of SOS before clinical/histological damage is established.

Real-world use of defibrotide for veno-occlusive disease/sinusoidal obstruction syndrome: the DEFIFrance Registry Study

Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of haematopoietic cell transplantation (HCT) conditioning. The DEFIFrance post-marketing registry study evaluated effectiveness and safety in patients who received defibrotide. It collected retrospective/prospective patient data from 53 French HCT centres from July 2014 to March 2020. Primary endpoints were survival and complete response (CR; total serum bilirubin <2 mg/dL, multiorgan failure resolution) at Day 100 post-HCT among patients with severe/very severe VOD/SOS. A secondary endpoint was evaluation of treatment-emergent serious adverse events (TESAEs) of interest. Of 798 patients analysed, 251 and 81 received defibrotide treatment for severe/very severe VOD/SOS and mild/moderate VOD/SOS post-HCT, respectively; 381 received defibrotide for VOD/SOS prophylaxis. In patients with severe/very severe VOD/SOS post-HCT, Kaplan-Meier-estimated CR at Day 100 was 74% (95% confidence interval [CI]: 66%, 81%). At Day 100, 137/251 (55%) were alive and in CR. Kaplan-Meier-estimated Day 100 post-HCT survival was 61% (95% CI: 55%, 67%) in patients with severe/very severe VOD/SOS. TESAEs of interest occurred in 29% of these patients; VOD/SOS-related mortality at 12 months was 15%. DEFIFrance represents the largest collection of real-world data on post-registration defibrotide use, supporting the real-world utility of defibrotide for patients with severe/very severe VOD/SOS post-HCT.

Case report: An infant boy with X-linked sideroblastic anaemia successfully treated by umbilical cord blood haematopoietic stem cell transplantation

X-linked sideroblastic anaemia (XLSA) is an inherited disorder caused by mutations in genes encoding proteins involved in the biosynthesis of haem. The pathogenic gene, as well as the pathogenesis and diagnosis of XLSA, have been fully elucidated in previous studies. However, only a few new advances have been made in managing XLSA in recent years, and blood transfusion remains the primary treatment. We report a case of umbilical cord blood haematopoietic stem cell transplantation in a male infant diagnosed with XLSA who was born with asphyxia due to severe anaemia. Early hepatic vein occlusion occurred after transplantation. However, this complication was rapidly controlled after active treatment, and the child’s quality of life improved significantly. Haematopoietic stem cell transplantation is a promising alternative treatment for XLSA.

A phase I study of inotuzumab ozogamicin as a single agent in pediatric patients in Japan with relapsed/refractory CD22-positive acute lymphoblastic leukemia (INO-Ped-ALL-1)

Inotuzumab ozogamicin (InO) is a CD22-directed antibody conjugated with calicheamicin approved for adult relapsed or refractory CD22-positive acute lymphoblastic leukemia (ALL). This phase 1 study primarily aimed to determine the pediatric recommended doses of InO through the standard 3 + 3 design, and to evaluate the safety, tolerability, pharmacokinetic (PK) profile, immunogenicity and efficacy of InO. Dose level 1 (DL1) was 1.8 mg/m² (days 1, 8, and 15: 0.8, 0.5, and 0.5 mg/m², respectively). Six of the seven registered patients were eligible [median age, 7.5 (2-17) years]. Although all six patients started DL1, only five completed the dose. No dose-limiting toxicity was observed. All patients experienced adverse events (AEs), including increased alanine aminotransferase and aspartate aminotransferase in four patients. Three patients experienced serious AEs, which were hepatic veno-occlusive disease (VOD), ALL, and fever. Five patients achieved complete remission (CR) or CR with incomplete blood cell recovery (CRi), among whom 3 (60%) were negative for minimal residual disease. PK findings were similar to those in adults. No patient had anti-drug antibodies to InO. In conclusion, InO was well tolerated in children and promoted similar antileukemic efficacy as in adults. Nonetheless, the risk for VOD requires attention.

Rapid and accurate method for quantifying busulfan in plasma samples by isocratic liquid chromatography-tandem mass spectrometry (LC-MS/MS)

Objectives

Administration of busulfan is extending rapidly as a part of a conditioning regimen in patients undergoing hematopoietic stem cell transplantation (HSCT). Monitoring blood plasma levels of busulfan is recommended for identifying the optimal dose in patients and for minimizing toxicity. The aim of this research was to validate a simple, rapid, and cost-effective analytical tool for measuring busulfan in human plasma that would be suitable for routine clinical use. This novel tool was based on liquid chromatography coupled to mass spectrometry.

Methods

Human plasma samples were prepared using a one-step protein precipitation protocol. These samples were then resolved by isocratic elution in a C18 column. The mobile phase consisted 2 mM ammonium acetate and 0.1% formic acid dissolved in a 30:70 ratio of methanol/water. Busulfan-d₈ was used as the internal standard.

Results

The run time was optimized at 1.6 min. Standard curves were linear from 0.03 to 5 mg/L. The coefficient of variation (%CV) was less than 8%. The accuracy of this method had an acceptable bias that fell within 85-115% range. No interference between busulfan and the interfering compound hemoglobin, lipemia, or bilirubin not even at the highest concentrations of compound was tested. Neither carryover nor matrix effects were observed using this method. The area under the plasma drug concentration-time curves obtained for 15 pediatric patients who received busulfan therapy prior to HSCT were analyzed and correlated properly with the administered doses.

Conclusions

This method was successfully validated and was found to be robust enough for therapeutic drug monitoring in a clinical setting.

Herpes zoster prophylaxis: Essential for treating newly diagnosed multiple myeloma patients

BACKGROUND

Multiple myeloma (MM) is known for its immune disturbance and patients suffering from MM are thus vulnerable to opportunistic infections, including herpes zoster (HZ). As HZ infection remarkably affects patients' quality of life and poses huge economic burdens on the health system, we aim to identify the risk factors of HZ infection and evaluate the effects of different dosages, types, and durations of anti-HZ prophylaxis drugs to prevent HZ infection.

METHODS

551 MM patients at Taipei Veterans General Hospital in Taiwan between January 1, 2009 and August 31, 2021 were restrospectively analyzed. The patients' baseline characteristics were recorded. The primary endpoint of the study was the incidence of HZ infection among the studied patient population. Due to the lack of cost coverage from Taiwanese public health insurance on HZ prophylaxis drugs, the use of anti-HZ drugs mainly depends on physicians' preferences and patients' choices.

RESULTS

In our study, prophylaxis was given to 283 of the patients. In the multivariate analysis, we included non-prophylaxis, age ≥ 60, corrected serum calcium ≥12 mg/dl, serum creatinine ≥2 mg/dl, serum β2-microglobulin ≥5500 mg/L, autologous stem cell transplant (SCT), and allogeneic SCT for analysis. Our results demonstrated that the non-prophylaxis group (HR: 2.37, 95% CI 1.57-3.57) and patients receiving autologous SCT (HR: 2.22, 95% CI 1.28-3.86) and allogeneic SCT (HR: 5.12, 95% CI 1.13-23.22) had higher risk of HZ infection. The difference in dosage and types of anti-HZ drugs showed similar protective effects. In patients who stopped anti-HZ prophylaxis before active cancer-related treatment, a higher risk of getting HZ infection compared to the corresponding group was also observed (adjusted HR 3.09, 95% CI 1.35-7.07, p = 0.008).

CONCLUSIONS

We concluded that MM patients should receive HZ prophylaxis drugs while receiving active cancer-related treatment. Patients receiving SCT are also at high risk of getting HZ infection, even under prophylaxis.

Interest of the preventive and curative use of defibrotide on the occurrence and severity of sinusoidal obstruction syndrome after hematopoietic stem cell transplant in children

Defibrotide (DF) is indicated for the treatment of severe sinusoidal obstruction syndrome (SOS) following hematopoietic stem cell transplantation (HSCT), but its prophylactic use against SOS is not recommended yet. This study describes the impact of the preventive and curative use of DF on reducing the incidence and severity of SOS in children. Patients aged 0-19 years, who received allogenic HSCT after myeloablative conditioning regimen with busulfan or total body irradiation in our comprehensive cancer center, between 2013 and 2017, were included. The Baltimore or modified Seattle criteria were used for SOS diagnosis. SOS was graded using the 2017 European Society for Blood and Marrow Transplantation classification defining severity criteria of SOS in children. SOS occurrence tended to decrease with prophylactic DF, but no significant difference was observed in terms of severity. When not treated with preventive DF, 50% (19/38) of the patients with SOS were graded severe to very severe, but only 37% (7/19) had organ dysfunction. Curative DF was administered at a median of 2 days post-HSCT, for a median of 6.5 days. The absence of fatal SOS supports the use of early curative DF with acceptable toxicities and questions the optimal duration of DF treatment.

Abdominal Complications During Treatment for Pediatric Acute Myeloid Leukemia

Acute myeloid leukemia (AML) accounts for 15% to 20% of childhood leukemias. Because of high-intensive therapy, up to 5% of patients suffer from treatment-related mortality (TRM). Abdominal complications are frequent, however, literature on this subject is sparse. We aimed to characterize severe abdominal pain (AP) and hyperbilirubinemia experienced by pediatric AML patients treated according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO)-AML 2004 protocol (n=313). Patients were censored at hematopoietic stem cell transplantation and relapse. Toxicity information was collected prospectively. Additional information was requested retrospectively from the treating centers. Sixteen episodes of hyperbilirubinemia and 107 episodes of AP were reported. The treating centers deemed infection (30%) and typhlitis (18%) as the most frequent causes of AP. Six patients developed appendicitis (2%). Patients experiencing concurrent AP and sepsis had a high risk of TRM (36%, n=4). Eighty percent of episodes with hyperbilirubinemia fulfilled the European Society for Bone and Marrow Transplantation criteria for sinusoidal obstruction syndrome. In conclusion, abdominal complications were frequent with infection considered the predominate cause. Most patients with hyperbilirubinemia fulfilled the criteria for sinusoidal obstruction syndrome. AML treatment might be associated with appendicitis. Patients suffering from concurrent AP and sepsis had a high risk of TRM indicating that high awareness of abdominal complications is essential to reduce mortality, especially during sepsis.

Advantages of peripheral blood stem cells from unrelated donors versus bone marrow transplants in outcomes of adult acute myeloid leukemia patients

BACKGROUND AIMS

In allogeneic stem cell transplantation, unrelated donors are chosen in cases where appropriate related donors are not available. Peripheral blood stem cells (PBSCs) are more often selected as a graft source than bone marrow (BM). However, the prognostic benefits of PBSCs versus BM transplants from unrelated donors have not been carefully examined in patients with acute myeloid leukemia (AML). This study compared outcomes of adult AML patients who underwent unrelated PBSC and BM transplantation, evaluating post-transplant complications, including engraftment, graft-versus-host disease (GVHD) and infections, and determined subgroups of patients who are most likely to benefit from unrelated PBSCs compared with BM transplants.

METHODS

The authors analyzed 2962 adult AML patients who underwent unrelated PBSC or BM transplants between 2011 and 2018 (221 PBSC and 2741 BM) using the Japanese nationwide registry database, in which graft source selection is not skewed toward PBSCs.

RESULTS

In 49.7% of patients, disease status at transplantation was first complete remission (CR1). In 57.1% of cases, HLA-matched donors were selected. Myeloablative conditioning was performed in 75.1% of cases, and anti-thymocyte globulin (ATG) was added to conditioning in 10.5%. Multivariate analyses showed a trend toward favorable non-relapse mortality (NRM) in PBSC recipients compared with BM recipients (hazard ratio [HR], 0.731, P = 0.096), whereas overall survival (OS) (HR, 0.959, P = 0.230) and disease-free survival (DFS) (HR, 0.868, P = 0.221) were comparable between PBSC and BM recipients. Although the rate of chronic GVHD (cGVHD) was significantly higher in PBSC patients (HR, 1.367, P = 0.016), NRM was not increased, mainly as a result of significantly reduced risk of bacterial infections (HR, 0.618, P = 0.010), reflecting more prompt engraftments in PBSC recipients. Subgroup analyses revealed that PBSC transplantation was advantageous in patients transplanted at CR1 and in those without ATG use. PBSC recipients experienced significantly better OS and/or DFS compared with BM recipients in this patient group.

CONCLUSIONS

The authors' results confirmed the overall safety of unrelated PBSC transplantation for adult AML patients and suggested an advantage of PBSCs, especially for those in CR1. Further optimization of the prophylactic strategy for cGVHD is required to improve the overall outcome in transplantation from unrelated PBSC donors.

Journey of a Patient With Multiple Myeloma Undergoing Autologous Stem Cell Transplantation

Multiple myeloma accounts for 10% of all hematologic malignancies. It has been drawn to the forefront of clinical interest because of recent advances in treatment regimens. Although there are multiple lines of available therapies and ongoing clinical trials, autologous stem cell transplantation remains the central option for prolonging durations of remission and improving overall survival. This case study demonstrates how oncology nurses play a critical role in patients' journeys before and after autologous stem cell transplantation.

Therapeutic Plasma Exchange in Pediatric Patients With Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease After Hematopoietic Stem Cell Transplantation: A Single-Center Experience

OBJECTIVES

Sinusoidal obstruction syndrome/venoocclusive disease is a significant complication of hematopoietic stem cell transplantation. Due to high mortality rates, new treatment strategies have been investigated. Here, we have presented outcomes of therapeutic plasma exchange performed on patients with sinusoidal obstruction syndrome/veno-occlusive disease.

MATERIAL AND METHODS

Our study included 70 pediatric patients diagnosed with sinusoidal obstruction syndrome/veno-occlusive disease. Therapeutic plasma exchange procedures in patients were evaluated retrospectively.

RESULTS

There were 9 mild (12.9%), 9 moderate (12.9%), 21 severe (30%), and 31 very severe (44.2%) cases of sinusoidal obstruction syndrome/venoocclusive disease. Therapeutic plasma exchange was performed in 31 of the 70 study patients (59.6%). Moreover, 10/21 patients with severe (47.6%) and 21/31 patients with very severe (67.7%) disease underwent plasma exchange. Mean time from diagnosis of sinusoidal obstruction syndrome/venoocclusive disease to therapeutic plasma exchange initiation was 2.3 days. The 31 patients who received therapeutic plasma exchange had a total of 146 sessions. Overall survival rates at 100 days were 87.1% and 92.3% for patients who did and did not undergo therapeutic plasma exchange, respectively. When patients with mild and moderate disease who were not expected to undergo plasma exchange were excluded (n = 52), 100-day overall survival rates were 87.1% and 90.5% for those who did and did not undergo plasma exchange, respectively. When we compared severe versus very severe groups, no significant difference was found.

CONCLUSIONS

Plasmapheresis had no positive effect on survival. However, overall survival in all groups was higher than that in the literature, despite the high number of patients with severe and very severe disease. Interpretation of the results is limited by the retrospective nature of the study. Thus, prospective, randomized controlled trials with larger numbers of patients are necessary to investigate the role of therapeutic plasma exchange in patients with sinusoidal obstruction syndrome/veno-occlusive disease.

Early vascular toxicity after pediatric allogeneic hematopoietic stem cell transplantation

Treatment-related mortality and morbidity remain a challenge in hematopoietic stem cell transplantation (HSCT). In this retrospective, single-center study, we analyzed endothelial damage as a potential, common denominator and mechanism for the adverse effects. We evaluated the prevalence of key vascular complications and graft-versus-host disease among 122 pediatric patients with an allogeneic HSCT between 2001 and 2013. The spectrum and frequency of acute adverse events emerging ≤100 days post transplant were graded according to the CTCAE 4.03 and analyzed. We identified a total of 19/122 (15.6%) patients with vascular complications, fulfilling the criteria of capillary leak syndrome, veno-occlusive disease/sinusoidal obstruction syndrome or thrombotic microangiopathy. The patients had a poorer overall survival (77% versus 26%, p < 0.001). Nearly one half (56/122, 45.9%) had at least one, severe (grade 3 or 4) adverse event. Patients with vascular complications had more often edema/effusions (p = 0.023), thrombocytopenia (p = 0.001), gastrointestinal bleeding (p < 0.001), acute kidney injury (p < 0.001), ascites (p < 0.001) or bilirubin increase (p = 0.027). These endotheliopathy-related adverse events appeared early post HSCT, varied in their clinical phenotype and predicted a poor outcome. An unrelated donor but not previous exposure to leukemia or irradiation-based conditioning was identified as a risk factor for vascular complications and endotheliopathy.

Low-dose unfractionated heparin prophylaxis is a safe strategy for the prevention of hepatic sinusoidal obstruction syndrome after myeloablative adult allogenic stem cell transplant

Hepatic sinusoidal obstruction syndrome (SOS) is a serious complication after allogeneic stem cell transplantation (allo-HCT). However, there is no uniform consensus on the optimal strategy for SOS prevention. Ursodeoxycholic acid is the most used regimen, even though its administration is challenging in recipients unable to tolerate oral medication. Defibrotide was recently studied in a phase 3 trial, but enrollment was stopped early due to futility. Low dose unfractionated heparin (UFH) is an alternative strategy. However, its efficacy is reputed but unproven increased risk of bleeding has not been fully established. We evaluated 514 adult allo-HCT recipients who received SOS prophylaxis with low dose UFH. Bleeding complications occurred in 12 patients 2.3% of patients of which only 2 (0.4%) had significant grade 3 bleeding. Only 14 patients were diagnosed with hepatic SOS. Univariate analysis showed that day 100 SOS was higher in recipients of unmodified grafts when compared to CD34+ selected ex vivo T-cell depleted grafts (p ≤ 0.001), and patients with hepatitis B and/or C exposure pre-HCT (p = 0.028). Overall, UFH was well tolerated and associated with a low incidence of subsequent hepatic SOS. Low dose UFH prophylaxis can be considered in select patients who cannot tolerate oral ursodiol.

Single-dose (4.5 mg/m2 ) gemtuzumab ozogamicin in combination with fludarabine, cytarabine and anthracycline as reinduction therapy in relapsed or refractory paediatric acute myeloid leukaemia

Despite major therapeutic improvements, children with relapsed/refractory Acute Myeloid Leukaemia still have poor outcomes and overall survival does not exceed 40%. New treatments are required to improve their outcome; Gemtuzumab ozogamicin (GO), an anti-CD33 immunoconjugate antibody, is a potent cytotoxic agent whose efficacy has been demonstrated mainly in adults. The main objective of this retrospective multicentre study was to assess the outcome of children treated, between February 2008 and August 2019, with GO at a single 4.5 mg/m² dose, in combination with Fludarabine, Cytarabine and antssshracyclines, in context of a first relapse (n = 26) or refractory disease (n = 3). The remission rate was 83% (24/29 children) and 20 children (69%) were allografted. With a median follow-up of 1.2 years (range: 0.1-8), the overall survival was 49% (CI95% = 33; 72). Most common adverse event was febrile neutropenia with microbiological identification in 55% of cases. Veno-occlusive disease occurred in 6 patients (21%), of which 5 subvened after bone marrow transplantation, and resolved within 2-32 days (median 10.5 days). Administration of GO in combination with FLA-anthracyclines chemotherapy appears to be a good reinduction regimen for relapsed or refractory AML with a good safety profile. These results warrant larger prospective study.