Microcavity-assisted cloning (MAC) of hard-to-clone HepG2 cell lines: cloning made easy.

Cloning is a key molecular biology procedure for obtaining a genetically homogenous population of organisms or cell lines. It requires the expansion of new cell populations starting from single genetically modified cells. Despite the technical progress, cloning of many cell lines remains difficult. Cloning often fails either due to the strenuous conditions associated with manipulating cells or because many cells don't tolerate a single-cell state. Here we describe a new cloning method utilizing low adhesion microcavity plates. This new technique, named microcavity-assisted cloning (MAC) was developed to clone difficult-to-clone HepG2 cells. The clones were produced following CRISPR/Cas9 knockout of the GSTA1 gene by a random distribution of 200, 400, and 800 cells into 550 microcavities of a 24-well low adhesion plate originally designed for the culture of spheroids. The knockout of GSTA1 was verified at the protein level using Western blotting. The advantages of the MAC method are its low cost, ease of the procedure, and the possibility of scaling up the throughput and automatization.

Long-term follow-up of a child with EWSR1-BEND2 fused spinal astroblastoma.

INTRODUCTION: Spinal astroblastoma is a rare highly malignant tumor that mainly affects children. We review the few cases described in the literature and highlight the challenges of managing this neoplasm by illustrating a case recently treated at our institutions. To our knowledge, this is the first published case of EWSR1-BEND2 fused spinal astroblastoma with long-term follow-up. CASE PRESENTATION: An 8-year-old girl was transferred from her home country to Switzerland for treatment of a recurrent intramedullary tumor of the cervical spine extending from C2-C7. The tumor was primarily diagnosed as an ependymoma of the spinal cord. Prior to her transfer to our department, the patient had undergone subtotal resection of the lesion, radiation therapy, multiple chemotherapy regimens, and biopsy of the recurrent tumor. Clinically, the patient presented with tetraparesis and had recently experienced worsening upper extremity weakness with complete loss of hand function. We performed a near total resection of the recurrent tumor. Ultra-fast Nanopore seq® based DNA methylome profiling allowed confirmation of the molecular diagnosis of a high-grade neuroepithelial tumor (HGNET-MN1) consistent with astroblastoma in less than 2 hours, with subsequent molecular workup revealing a EWSR1-BEND2 fusion. After surgery, the patient gradually regained function in her hands. She was sent to a specialized pediatric rehabilitation center, and while the tumor was being followed radiologically with no adjuvant treatment planned, the patient presented with a relapse of the tumor in only 3 months. Given the acute worsening of radiating pain and sudden respiratory failure, a cervical decompression was performed. MRI of the cervical spine showed infiltration of the lower aspects of the brainstem. The patient was offered palliative comfort care. CONCLUSION: Spinal astroblastoma is a rare and highly aggressive tumor affecting children and young adults with a high recurrence rate and thus far not well-defined prognosis. The molecular signature of astroblastoma needs to be further characterized to establish a treatment-relevant classification and to allow a better prognostication. Currently, gross total resection combined with radiotherapy remains the mainstay of treatment for spinal astroblastoma.

Single-cell transcriptome analysis reveals atypical monocytes circulating ahead of acute graft-versus-host disease clinical onset.

Acute graft-versus-host disease (aGVHD) represents the rejection of the recipient's skin, gut, and liver tissues of an allogeneic hematopoietic stem cell transplantation (HSCT) by the donor T-cells. The onset of aGVHD is often rapid and its evolution is unpredictable. We undertook the single-cell RNA sequencing of peripheral blood mononuclear cells (PBMCs) collected before aGVHD clinical onset in three patients and from one patient afterward. We used four HSCT recipients who remained free of aGVHD as controls. This analysis unveiled the presence of particular subpopulations of circulating monocytes and cytotoxic T cells (CTLs) in pre-aGVHD samples up to 18 days before clinical disease. These pre-aGVHD monocytes were characterized by an upregulation of the M2 polarity marker CD163 and the transmembrane protein SIGLEC1/CD169. At the same time, their CTL counterparts stood out for the upregulation of the CXCL10 receptor CXCR3 and the antigenic stimulation marker CD70. The occurrence of CD163/SIGLEC1 co-expressing monocytes upstream of aGVHD onset was validated using transcriptomic data from an independent cohort and by flow cytometry in additional blood samples. These findings point to potential early diagnostic tools and preventive therapeutic strategies for aGVHD.

Upfront or delayed surgery in resectable hepatoblastoma: analysis from the children's hepatic tumors international collaboration database.

Background: In the treatment of resectable hepatoblastoma (HB), it has not been established whether upfront surgery (UF) at diagnosis or neoadjuvant chemotherapy and delayed surgery (DL) is preferred. We compared patients with localized HB who underwent either UF, or DL after neoadjuvant chemotherapy in the Children's Hepatic tumors International Collaboration (CHIC) database of 1605 cases enrolled in eight multicenter hepatoblastoma trials between 1988 and 2010. Methods: Among the 512 resectable HB patients who had PRETEXT (PRETreament EXTent of disease) I or II unruptured tumors at diagnosis without extrahepatic invasion, distant metastases, or massive vascular invasion, 172 underwent UF and 340 underwent DL. The primary outcomes were event-free and overall survivals after start of treatment in these two groups. Survival analysis was performed using the Kaplan-Maier analysis with long-rank tests and multivariable Cox regression models. Findings: Complete resection rates were comparable (93.6% in UF and 89.7% in DL). The total cycles of chemotherapy of DL (median:6) were significantly more than those of UF (median:4) (P < 0.01). The 5-year event-free survival (EFS) was 90.6% and 86.6% (P = 0.89) in the UF and DL cohorts, respectively. The surgical complications, recurrence rates, and late complications were not significantly different between the cohorts but the EFS rates of DL patients with a low alpha-fetoprotein (AFP) level (100-999 ng/mL) or older age at diagnosis (≥3 years old) were significantly worse than others. Interpretation: The outcomes, surgical resectability, and complications were not significantly different between the UF and DL groups. Eligible patients with a low AFP level (<1000 ng/mL) or older age (≥3 years old) showed better outcomes in the UF group and might be considered for initial resection. Funding: European Network for Cancer Research in Children and Adolescents, funded through the Framework Program 7 of the European Commission; Children's Oncology Group Cure Search grant contributed by the Hepatoblastoma Foundation; Practical Research for Innovative Cancer Control and Project Promoting Clinical Trials for Development of New Drugs and Medical Devices, Japan Agency for Medical Research and Development; Japan Society for the Promotion of Science; and Swiss Cancer Research grant.

Parental smoking and respiratory outcomes in young childhood cancer survivors.

BACKGROUND: Passive exposure to cigarette smoke has negative effects on respiratory health. Childhood cancer survivors (CCS) are at increased risk for respiratory disease due to treatment regimens that may harm the respiratory system. The objective of this study was to assess the prevalence of parental smoking among CCS and investigate its association with respiratory outcomes. PROCEDURE: As part of the Swiss Childhood Cancer Survivor Study, between 2007 and 2022, we sent questionnaires to parents of children aged ≤16 years who had survived ≥5 years after a cancer diagnosis. Parents reported on their children's respiratory outcomes including recurrent upper respiratory tract infections (otitis media and sinusitis), asthma, and lower respiratory symptoms (chronic cough persisting >3 months, current and exercise wheeze), and on parental smoking. We used multivariable logistic regression to investigate associations between parental smoking and respiratory outcomes. RESULTS: Our study included 1037 CCS (response rate 66%). Median age at study was 12 years (interquartile range 10-14 years). Eighteen percent of mothers and 23% of fathers reported current smoking. CCS exposed to smoking mothers were more likely to have recurrent upper respiratory tract infections (OR 2.1; 95%CI 1.1-3.7) and lower respiratory symptoms (OR 2.0; 95%CI 1.1-3.7). We found no association with paternal smoking. CONCLUSIONS: A substantial proportion of CCS in Switzerland have parents who smoke. Exposure to maternal smoking was associated with higher prevalence of upper and lower respiratory problems. Healthcare providers can support families by addressing caregiver smoking behaviors and providing referrals to smoking cessation programs.

Caplacizumab as an add-on therapy in a 7-year-old girl with exacerbated immune-mediated thrombotic thrombocytopenic purpura, a case report and literature review.

The cornerstone treatment for immune-mediated thrombotic thrombocytopenic purpura (iTTP) in children is a combination of therapeutic plasma exchange (TPE), corticosteroids, and rituximab. Caplacizumab is an anti-von Willebrand factor (VWF) NANOBODY molecule approved as a frontline therapy of iTTP for adults and children aged ≥12 years. Using caplacizumab in children aged <12 years remains a gray area based on recommendations but with no marketing authorization. We report the first case of a pediatric patient with iTTP successfully treated with a caplacizumab dose adjustment of 5 mg daily based on ADAMTS13 activity. We also review all published cases of iTTP in children aged <12 years treated with caplacizumab. This is a 7-year-old girl with clinical thrombotic microangiopathy, in the absence of diarrhea and kidney injury. With a French score of 2 and a PLASMIC score of 7 (high risk), the diagnosis of TTP was suspected and later confirmed by severely low ADAMTS13 activity (<5%). Immune-mediated TTP was distinguished from the congenital one due to the presence of a functional ADAMTS13 inhibitor. Daily TPE and intravenous corticosteroids were started on day 0 (D0). Rituximab was added on D4, and due to refractoriness under daily TPE, we considered off-label administration of caplacizumab from D12. A clinical answer, with a significant increase in the platelet count, was observed within 48 h. A complete ADAMTS13 recovery was reached on D62. No major adverse events were observed during the treatment. She was discharged from the hospital over 3 months ago with a platelet count still within normal ranges. In the literature, we identified a total of four case reports describing five iTTP patients aged <12 years treated with caplacizumab, with a 100% success and tolerability rate. These published data attest to the efficacy and safety of the systematic use of caplacizumab and rituximab as frontline therapy in pediatric iTTP under 12 years of age. Therefore, prospective data are needed to support commercial authorization of caplacizumab in this subpopulation. Close monitoring of ADAMTS13 activity is particularly of interest among children to limit the number of caplacizumab injections.

A practical guide to therapeutic drug monitoring in busulfan: recommendations from the Pharmacist Committee of the European Society for Blood and Marrow Transplantation (EBMT).

Busulfan (Bu) is an important component of many conditioning regimens for allogeneic hematopoietic cell transplantation. The therapeutic window of Bu is well characterized, with strong associations between Bu exposure and the clinical outcome in adults (strongest evidence in myelo-ablative setting) and children (all settings). We provide an overview of the literature on Bu as well as a step-by-step guide to the implementation of Bu therapeutic drug monitoring (TDM). The guide covers the clinical, pharmacological, laboratory and administrative aspects of the procedure. Through this document, we aim to support centers in implementing TDM for Bu to further enhance the success rates of HCT and improve patient outcomes. The Pharmacist Committee of the European Society for Blood and Marrow Transplantation (EBMT) encourages all centers to perform TDM for Bu in the aforementioned indications.

Association of busulfan exposure and outcomes after HCT for patients with an inborn error of immunity.

ABSTRACT: Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative treatment strategy for patients with inborn errors of immunities (IEIs). The objective of this study was to assess the optimal busulfan exposure before allogeneic HCT for patients with an IEI who received an IV busulfan-based conditioning regimen. Patients from 17 international centers were included. The main outcome of interest was event-free survival (EFS). Patients were categorized into 4 IEI subgroups: combined immunodeficiency (CID), severe combined immunodeficiency (SCID), neutrophil disorders, and hemophagocytic lymphohistiocytosis (HLH)-related disorders. Busulfan exposure was calculated by individual centers (area under the curve [AUC]CENTER) and re-estimated using a nonlinear mixed-effects model (NONMEM; exposure defined as AUCNONMEM). Overall, 562 patients were included: 173 (30.8%) with CID, 154 (27.4%) with SCID, 101 (18.0%) with HLH-related disorders, and 134 (23.8%) with neutrophil disorders. The median busulfan AUCNONMEM was 69.0 mg × h/L and correlated poorly with the AUCCENTER (r2 = 0.54). In patients with SCID, HLH-related, and neutrophil disorders with a busulfan AUCNONMEM of 70 to 90 mg × h/L, 2-year EFS was superior to <70 mg × h/L, and >90 mg ×h/L. Full donor chimerism increased with higher busulfan AUCNONMEM, plateauing at 90 mg × h/L. For patients with CID, the optimal AUCNONMEM for donor chimerism was found to be >70 mg × h/L. Improved EFS and higher donor chimerism may be achieved by targeting a cumulative busulfan AUCNONMEM of 80 mg × h/L (range, 70-90). Our study stresses the importance of uniformly using a validated population pharmacokinetic model to estimate AUCNONMEM.

Simulation-Based Optimization of Sampling Schedules for Model-Informed Precision Dosing of Once-Daily and 4-Times-Daily Busulfan in Pediatric Patients.

BACKGROUND: Therapeutic drug monitoring (TDM) is crucial in optimizing the outcomes of hematopoietic stem cell transplantation by guiding busulfan (Bu) dosing. Limited sampling strategies show promise for efficiently adjusting drug doses. However, comprehensive assessments and optimization of sampling schedules for Bu TDM in pediatric patients are limited. We aimed to establish optimal sampling designs for model-informed precision dosing (MIPD) of once-daily (q24h) and 4-times-daily (q6h) Bu administration in pediatric patients. METHODS: Simulated data sets were used to evaluate the population pharmacokinetic model-based Bayesian estimation of the area under the concentration-time curve (AUC) for different limited sampling strategy designs. The evaluation was based on the mean prediction error for accuracy and root mean square error for precision. These findings were validated using patient-observed data. In addition, the MIPD protocol was implemented in the Tucuxi software, and its performance was assessed. RESULTS: Our Bayesian estimation approach allowed for flexible sampling times while maintaining mean prediction error within ±5% and root mean square error below 10%. Accurate and precise AUC0-24h and cumulative AUC estimations were obtained using 2-sample and single-sample schedules for q6h and q24h dosing, respectively. TDM on 2 separate days was necessary to accurately estimate cumulative exposure, especially in patients receiving q6h Bu. Validation with observed patient data confirmed the precision of the proposed limited sampling scenarios. Implementing the MIPD protocol in Tucuxi software yielded reliable AUC estimations. CONCLUSIONS: Our study successfully established precise limited sampling protocols for MIPD of Bu in pediatric patients. Our findings underscore the importance of TDM on at least 2 occasions to accurately achieve desired Bu exposures. The developed MIPD protocol and its implementation in Tucuxi software provide a valuable tool for routine TDM in pediatric hematopoietic stem cell transplantation.

Haplotype Inference Using Long-Read Nanopore Sequencing: Application to GSTA1 Promoter.

Recovering true haplotypes can have important clinical consequences. The laboratory process is difficult and is, therefore, most often done through inference. In this paper, we show that when using the Oxford nanopore sequencing technology, we could recover the true haplotypes of the GSTA1 promoter region. Eight LCL cell lines with potentially ambiguous haplotypes were used to characterize the efficacy of Oxford nanopore sequencing to phase the correct GSTA1 promoter haplotypes. The results were compared to Sanger sequencing and inferred haplotypes in the 1000 genomes project. The average read length was 813 bp out of a total PCR length of 1336 bp. The best coverage of sequencing was in the middle of the PCR product and decreased to 50% at the PCR ends. SNPs separated by less than 200 bp showed > 90% of correct haplotypes, while at the distance of 1089 bp, this proportion still exceeded 58%. The number of cycles influences the generation of hybrid haplotypes but not extension or annealing time. The results demonstrate that this long sequencing reads methodology, can accurately determine the haplotypes without the need for inference. The technology proved to be robust but the success of phasing nonetheless depends on the distances and frequencies of SNPs.

Use of Sodium Thiosulfate as an Otoprotectant in Patients With Cancer Treated With Platinum Compounds: A Review of the Literature.

PURPOSE: Hearing loss occurs in 50%-70% of children treated with cisplatin. Scientific efforts have led to the recent approval of a pediatric formula of intravenous sodium thiosulfate (STS) for otoprotection by the US Food and Drug Administration, the European Medicines Agency, and the Medicines and Health Regulatory Authority in the United Kingdom. To inform stakeholders regarding the clinical utility of STS, the current review summarizes available literature on the efficacy, pharmacokinetics (PK), and safety of systemic STS to minimize cisplatin-induced hearing loss (CIHL). DESIGN: A comprehensive narrative review is presented. RESULTS: Thirty-one articles were summarized. Overall, systemic STS effectively reduces CIHL in the preclinical and controlled clinical study settings, in both adults and children with cancer. The extent of CIHL reduction depends on the timing and dosing of STS in relation to cisplatin. Both preclinical and clinical data suggest that systemic STS may affect plasma platinum levels, but studies are inconclusive. Delayed systemic administration of STS, at 6 hours after the cisplatin infusion, does not affect cisplatin-induced inhibition of tumor growth or cellular cytotoxicity in the preclinical setting, nor affect cisplatin efficacy and survival in children with localized disease in the clinical setting. CONCLUSION: Systemic administration of STS effectively reduces the development and degree of CIHL in both the preclinical and clinical settings. More studies are needed on the PK of STS and cisplatin drug combinations, the efficacy and safety of STS in patients with disseminated disease, and the ability of STS to prevent further deterioration of pre-established hearing loss.

Exploring grandparents' psychosocial responses to childhood cancer: A qualitative study.

OBJECTIVE: A childhood cancer diagnosis is a traumatic experience for patients and their families. However, little is known about the effect on grandparents. We aimed to investigate the negative psychosocial impact, coping strategies, and positive outcomes of grandparents of childhood cancer patients in Switzerland. METHODS: We collected data using a semi-structured interview guide and applied qualitative content analysis. RESULTS: We conducted 20 interviews with 23 grandparents (57% female; mean age = 66.9 years; SD = 6.4; range = 57.0-82.4) of 13 affected children (69% female; mean age = 7.5 years; SD = 6.1; range = 1.0-18.9) between January 2022 and April 2023. The mean time since diagnosis was 1.0 years (SD = 0.5; range = 0.4-1.9). Grandparents were in shock and experienced strong feelings of fear and helplessness. They were particularly afraid of a relapse or late effects. The worst part for most was seeing their grandchild suffer. Many stated that their fear was always present which could lead to tension and sleep problems. To cope with these negative experiences, the grandparents used internal and external strategies, such as accepting the illness or talking to their spouse and friends. Some grandparents also reported positive outcomes, such as getting emotionally closer to family members and appreciating things that had previously been taken for granted. CONCLUSIONS: Grandparents suffer greatly when their grandchild is diagnosed with cancer. Encouragingly, most grandparents also reported coping strategies and positive outcomes despite the challenges. Promoting coping strategies and providing appropriate resources could reduce the psychological burden of grandparents and strengthen the whole family system.

Brain stem tumors in children less than 3 months: Clinical and radiologic findings of a rare disease.

PURPOSE: Brain stem tumors in children < 3 months at diagnosis are extremely rare. Our aim is to study a retrospective cohort to improve the understanding of the disease course and guide patient management. METHODS: This is a multicenter retrospective analysis across the European Society for Pediatric Oncology SIOP-E HGG/DIPG Working Group linked centers, including patients with a brainstem tumor diagnosed between 2009 and 2020 and aged < 3 months at diagnosis. Clinical data were collected, and imaging characteristics were analyzed blindly and independently by two neuroradiologists. RESULTS: Five cases were identified. No patient received any therapy. The epicenter of two tumors was in the medulla oblongata alone and in the medulla oblongata and the pons in three. For patients with tumor in equal parts in the medulla oblongata and the pons (n = 3), the extension at diagnosis involved the spinal cord; for the two patients with the tumor epicenter in the medulla oblongata alone (n = 2), the extension at diagnosis included the pons (n = 2) and the spinal cord (n = 1). Biopsy was performed in one patient identifying a pilocytic astrocytoma. Two patients died. In one patient, autopsy revealed a high-grade glioma (case 3). Three survivors showed either spontaneous tumor regression (n = 2) or stable disease (n = 1). Survivors were followed up for 10, 7, and 0.6 years, respectively. One case had the typical imaging characteristics of a dorsal exophytic low-grade glioma. CONCLUSIONS: No patient fulfilled the radiologic criteria defining a high-grade glioma. Central neuroradiological review and biopsy may provide useful information regarding the patient management.

The RELIVE consortium for relapsed or refractory pediatric hepatoblastoma and hepatocellular carcinoma: a scoping review of the problem and a proposed solution.

Liver tumors account for approximately 2% of all pediatric malignancies. Children with advanced stages of hepatoblastoma (HB) are cured only 50-70% of the time while children with advanced hepatocellular carcinoma (HCC) have a <20% 5-year overall survival. This scoping review was performed to highlight the paucity of rigorous, reliable data guiding the management of relapsed pediatric HB or HCC. When these patients are enrolled on prospective trials, the trials are often histology-agnostic, exclude patients less than a year of age, lack a liquid formulary of the drug under study, exclude recipients of a solid organ transplant, and enroll only 1-2 patients limiting the ability to deduce efficacious regimens for current use or future study. We highlight the creation of a global pediatric consortium intended to source retrospective relapse data from over 100 institutions spanning 4 continents. The data collected from this effort will inform future relapse trials.

17q Gain in Neuroblastoma: A Review of Clinical and Biological Implications.

Neuroblastoma (NB) is the most frequent extracranial solid childhood tumor. Despite advances in the understanding and treatment of this disease, the prognosis in cases of high-risk NB is still poor. 17q gain has been shown to be the most frequent genomic alteration in NB. However, the significance of this remains unclear because of its high frequency and association with other genetic modifications, particularly segmental chromosomal aberrations, 1p and 11q deletions, and MYCN amplification, all of which are also associated with a poor clinical prognosis. This work reviewed the evidence on the clinical and biological significance of 17q gain. It strongly supports the significance of 17q gain in the development of NB and its importance as a clinically relevant marker. However, it is crucial to distinguish between whole and partial chromosome 17q gains. The most important breakpoints appear to be at 17q12 and 17q21. The former distinguishes between whole and partial chromosome 17q gain; the latter is a site of IGF2BP1 and NME1 genes that appear to be the main oncogenes responsible for the functional effects of 17q gain.

Low rate of nonrelapse mortality in under-4-year-olds with ALL given chemotherapeutic conditioning for HSCT: a phase 3 FORUM study.

ABSTRACT: Allogeneic hematopoietic stem cell transplantation (HSCT) is highly effective for treating pediatric high-risk or relapsed acute lymphoblastic leukemia (ALL). For young children, total body irradiation (TBI) is associated with severe late sequelae. In the FORUM study (NCT01949129), we assessed safety, event-free survival (EFS), and overall survival (OS) of 2 TBI-free conditioning regimens in children aged <4 years with ALL. Patients received fludarabine (Flu), thiotepa (Thio), and either busulfan (Bu) or treosulfan (Treo) before HSCT. From 2013 to 2021, 191 children received transplantation and were observed for ≥6 months (median follow-up: 3 years). The 3-year OS was 0.63 (95% confidence interval [95% CI], 0.52-0.72) and 0.76 (95% CI, 0.64-0.84) for Flu/Thio/Bu and Flu/Thio/Treo (P = .075), respectively. Three-year EFS was 0.52 (95% CI, 0.41-0.61) and 0.51 (95% CI, 0.39-0.62), respectively (P = .794). Cumulative incidence of nonrelapse mortality (NRM) and relapse at 3 years were 0.06 (95% CI, 0.02-0.12) vs 0.03 (95% CI: <0.01-0.09) (P = .406) and 0.42 (95% CI, 0.31-0.52) vs 0.45 (95% CI, 0.34-0.56) (P = .920), respectively. Grade >1 acute graft-versus-host disease (GVHD) occurred in 29% of patients receiving Flu/Thio/Bu and 17% of those receiving Flu/Thio/Treo (P = .049), whereas grade 3/4 occurred in 10% and 9%, respectively (P = .813). The 3-year incidence of chronic GVHD was 0.07 (95% CI, 0.03-0.13) vs 0.05 (95% CI, 0.02-0.11), respectively (P = .518). In conclusion, both chemotherapeutic conditioning regimens were well tolerated and NRM was low. However, relapse was the major cause of treatment failure. This trial was registered at www.clinicaltrials.gov as #NCT01949129.

Hematopoietic cell transplantation and cellular therapies in Switzerland. Evolution over 25 years. A report from the stem cell transplantation and cellular therapies working groups of the SBST 1997-2021.

The Swiss Blood Stem Cell Transplantation and Cellular Therapy Group (SBST) leads a mandatory national registry for all hematopoietic stem cell transplants (HCT) and cellular therapies. After 25 years, information was available for 11,226 patients receiving an HCT (4031 allogeneic and 7195 autologous), including 925 pediatric patients. We compared patient characteristics and outcome by quinquennia 1997-2001, 2002-2006, 2007-2011, 2012-2016, and 2017-2021. There were numerous changes over time. Allogeneic transplant recipients became older (median age 33.7 vs. 54.3) and had more frequently unrelated donors and reduced intensity conditioning in later quinquennia. Similarly, age increased for recipients of autologous HCT (median 48.3 vs. 59.9). We did not see a significant drop in transplant activity during the SARS-CoV-2 pandemic. Analysis of outcome showed overall survival (relative risk (RR) of death 0.664 (0.529-0.832) and progression free survival (RR 0.708 (0.577-0.870) being improved over time comparing the latest to the first quinquennium adjusting for risk factors. Non-relapse mortality decreased in recipients of allogeneic HCT (RR: 0.371 (0.270-0.509)) over time but relapse risks did not. Outcome of autologous HCT improved as well across quinquennia, this improvement was mainly due to decreased relapse risks (RR 0.681 (0.597-0.777)), possibly related to maintenance treatment or rescue treatment for relapse mainly in myeloma patients. Cellular therapies other than allogeneic or autologous HCT, particularly chimeric antigen receptor T-cells (CAR-T) treatment have started to increase after 2019, year of approval of the first commercial CAR-T product in Switzerland. Data on chimeric antigen receptor T-cell treatment are too early for comparative analyses. Detailed analyses of changes over time are presented. This study includes all HCTs, and cellular therapies, data useful for quality assurance programs, health care cost estimation and benchmarking. Between 50% and 60% of patients are long-term survivors after both types of HCT, indicating growing populations of surviving patients requiring long-term care.

Pharmacokinetic Modeling and Simulation with Pharmacogenetic Insights Support the Relevance of Therapeutic Drug Monitoring for Myeloablative Busulfan Dosing in Adult HSCT.

Therapeutic drug monitoring (TDM) of busulfan (Bu) is well-established in pediatric hematopoietic stem cell transplantation (HSCT), but its use in adults is limited due to a lack of clear recommendations and scarcity of evidence regarding its utility. GSTA1 promoter variants are reported to affect Bu clearance in both adults and pediatric patients. This study aimed to evaluate the value of preemptive genotyping GSTA1 and body composition (obesity) in individualizing Bu dosing in adults, through pharmacokinetic (PK) modeling and simulations. A population pharmacokinetic (PopPK) model was developed and validated with data from 60 adults who underwent HSCT. Simulations assessed different dosing scenarios based on body size metrics and GSTA1 genotypes. Due to the limited number of obese patients in the cohort, the effect of obesity on Bu pharmacokinetics (PK) was evaluated in silico using a physiologically-based pharmacokinetic (PBPK) model and relevant virtual populations from Simcyp software. Patients with at least 1 GSTA1*B haplotype had 17% lower clearance on average. PopPK simulations indicated that adjusting doses based on genotype increased the probability of achieving the target exposure (3.7 to 5.5 mg.h/L) from 53% to 60 % in GSTA1*A homozygous patients, and from 50% to 61% in *B carriers. Still, Approximately 40% of patients would not achieve this therapeutic window without TDM. A 2-sample optimal design was validated for routine model-based Bu first dose AUC0-∞ estimation, and the model was implemented in the Tucuxi user-friendly TDM software. PBPK simulations confirmed body surface area-based doses of 29 to 31 mg/m2/6h as the most appropriate, regardless of obesity status. This study emphasizes the importance of individualized Bu dosing strategies in adults to achieve therapeutic targets. Preemptive genotyping alone may not have a significant clinical impact, and routine TDM may be necessary for optimal transplantation outcomes.

Longitudinal assessment of lung function in Swiss childhood cancer survivors-A multicenter cohort study.

OBJECTIVE: Childhood cancer survivors are at risk for pulmonary morbidity due to exposure to lung-toxic treatments, including specific chemotherapeutics, radiotherapy, and surgery. Longitudinal data on lung function and its change over time are scarce. We investigated lung function trajectories in survivors over time and the association with lung-toxic treatments. METHODS: This retrospective, multicenter cohort study included Swiss survivors diagnosed between 1990 and 2013 and exposed to lung-toxic chemotherapeutics or thoracic radiotherapy. Pulmonary function tests (PFTs), including forced expiration volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, total lung capacity,  and diffusion capacity of the lung for carbon monoxide, were obtained from hospital charts. We calculated z-scores and percentage predicted, described lung function over time, and determined risk factors for change in FEV1 and FVC using multivariable linear regression. RESULTS: We included 790 PFTs from 183 survivors, with a median age of 12 years at diagnosis and 5.5 years of follow-up. Most common diagnosis was lymphoma (55%). Half (49%) of survivors had at least one abnormal pulmonary function parameter, mainly restrictive (22%). Trajectories of FEV1 and FVC started at z-scores of -1.5 at diagnosis and remained low throughout follow-up. Survivors treated with thoracic surgery started particularly low, with an FEV1 of -1.08 z-scores (-2.02 to -0.15) and an FVC of -1.42 z-scores (-2.27 to -0.57) compared to those without surgery. CONCLUSION: Reduced pulmonary function was frequent but mainly of mild to moderate severity. Nevertheless, more research and long-term surveillance of this vulnerable population is needed.