Prevalence of Duffy null and its impact on hydroxyurea in young children with sickle cell disease in the United States

Consistent with studies showing a high prevalence of the Duffy null phenotype among healthy Black Americans, this retrospective study found that Duffy null was present in >75% of a young and contemporary cohort of children with sickle cell disease (SCD) in the United States. Despite the potential for this phenotype to impact absolute neutrophil counts, hydroxyurea (HU) dosing, and outcomes, it was not associated with being prescribed a lower HU dose or having increased acute SCD visits early in the HU treatment course. Future studies are needed to confirm these findings in older children with SCD.

Final report of the phase II NEXT/CNS-GCT-4 trial: GemPOx followed by marrow-ablative chemotherapy for recurrent intracranial germ cell tumors

Background

Patients with relapsed intracranial germinoma can achieve durable remission with standard chemotherapy regimens and/or reirradiation; however, innovative therapies are required for patients with relapsed and/or refractory intracranial nongerminomatous germ cell tumors (NGGCTs) due to their poor prognosis. Improved outcomes have been reported using reinduction chemotherapy to achieve minimal residual disease, followed by marrow-ablative chemotherapy (HDCx) with autologous hematopoietic progenitor cell rescue (AuHPCR). We conducted a phase II trial evaluating the response and toxicity of a 3-drug combination developed for recurrent intracranial germ cell tumors consisting of gemcitabine, paclitaxel, and oxaliplatin (GemPOx).

Methods

A total of 9 patients with confirmed relapsed or refractory intracranial GCT were enrolled after signing informed consent, and received at least 2 cycles of GemPOx, of which all but 1 had relapsed or refractory NGGCTs. One patient with progressive disease was found to have pathologically confirmed malignant transformation to pure embryonal rhabdomyosarcoma (without GCT elements), hence was ineligible and not included in the analysis. Patients who experienced sufficient responses proceeded to receive HDCx with AuHPCR. Treatment response was determined based on radiographic tumor assessments and tumor markers.

Results

A total of 7 patients achieved sufficient response and proceeded with HDCx and AuHPCR, and 5 subsequently received additional radiotherapy. A total of 2 patients developed progressive disease while receiving GemPOx. Myelosuppression and transaminitis were the most common treatment-related adverse events. With a mean follow-up of 44 months, 4 patients (3 NGGCTs, 1 germinoma) are alive without evidence of disease.

Conclusions

GemPOx demonstrates efficacy in facilitating stem cell mobilization, thus facilitating the feasibility of both HDCx and radiotherapy.

Constipation and GI diagnoses in children with solid tumours: prevalence and management

OBJECTIVES

Despite continued development of targeted therapies for children with cancer, patients continue to experience an array of unwanted side effects. Children with solid tumours may experience constipation as a result of vinca alkaloid therapy, psychological stressors, periods of inactivity and opioid use. Our objective was to investigate the prevalence and treatment of constipation in hospitalised children with solid tumours treated with chemotherapy.

METHODS

We retrospectively analysed data from 48 children's hospitals in the Pediatric Health Information System, extracting patients 0-21 years of age with a solid tumour diagnosis hospitalised from October 2015 through December 2019.

RESULTS

We identified 13 375 unique patients with a solid tumour diagnosis receiving chemotherapy. Constipation was the most common gastrointestinal complaint with 8658 (64.7%; 95% Cl: 63.9% to 65.5%) having a constipation diagnosis or having received at least two laxatives during admission. Bone cancers had the highest percentage (69.9%) of patients with constipation, while Hodgkin's lymphoma had the lowest, although 52.1% of patients were affected. A total of 44% (n=35 301) of encounters received an opioid at some point during admission. Of patients receiving constipation medications, the most commonly prescribed was polyethyl glycol (n=25 175, 31.7%), followed by docusate (n=11 297, 14.2%), senna (n=10 325, 13.0%) and lactulose (n=5501, 6.9%).

CONCLUSIONS

Constipation is the most common gastrointestinal issue that children with solid tumours experience while receiving chemotherapy in the inpatient setting. Increased attention should be given to constipation prophylaxis and treatment in children with solid tumours undergoing chemotherapy, particularly those identified as high risk.

Pediatric arterial thrombosis: A single-institution cohort study of patient characteristics and thrombosis outcomes

BACKGROUND

Arterial thrombosis (AT) is an increasingly recognized complication in pediatrics. Consensus clinical practice guidelines suggest immediate removal of the indwelling arterial catheter and a short course (5-7 days) of anticoagulation. The optimal duration and modality of antithrombotic therapy in children are yet to be determined.

AIMS

Describe treatment patterns and outcomes in pediatric patients with AT and explore predictors for complete thrombus resolution or long-term complications.

METHODS

Single-institution retrospective study. Patients were identified by ICD-9 and ICD-10 codes for the diagnosis of AT or reports of AT on ultrasound from January 1, 2012, to October 1, 2022. Descriptive and logistic regression analyses were used.

RESULTS

101 patients were included. The median age was 2.2 months. The most common underlying diagnoses were congenital heart disease (39.6%) and infection (22.8%). A majority of patients had symptomatic thrombosis in an extremity, and 78% were catheter-associated. 81% of patients received anticoagulation with a median duration of 35 days. Out of the 70 patients who were treated with anticoagulation alone and had a follow-up imaging, 70% had complete resolution after 90 days of anticoagulation. No clear predictors of complete resolution were identified. Eighteen patients had long-term sequelae secondary to arterial insufficiency. Those with infection-associated AT were more likely to have long-term complications. The major and clinically relevant non-major bleeding rate was 11%.

CONCLUSION

Duration of anticoagulation was widely variable, and 70% of patients achieved complete resolution by 90 days of anticoagulation. A significant proportion of patients developed long-term sequelae secondary to arterial insufficiency. Sepsis/infection at the time of diagnosis with AT was more likely to be associated with long-term complications.

Development of a Novel Massage Therapy Outcome Measure for Children and Young Adults Receiving Hematopoietic Cell Transplant

Background

Children receiving hematopoietic stem cell transplantation (HCT) often experience an unfortunate sequalae of negative effects including pain, deconditioning, and anxiety. Massage therapy (MT) has demonstrated effective non-pharmacological management of fatigue, pain, and anxiety in patients undergoing cancer treatment. Existing studies have been limited by the lack of available MT-specific outcome measures to track responses to interventions.

Purpose

This study aimed to describe the creation of a novel MT-specific outcome measure to be utilized in the pediatric acute-care setting and establish construct validity for this measure to assess clinical effectiveness of MT interventions.

Setting

An oncology ward at a large pediatric tertiary medical center in the United States.

Participants

A total of 58 children and young adults undergoing HCT.

Research Design

Retrospective Cohort Study.

Intervention

A panel of massage therapists created a novel outcome measure, OMPREP, for use in MT sessions and performed a literature review to ensure face validity of the tool. This outcome measure was administered to patients and data were collected retrospectively to assess construct validity.

Results

A total of 1,333 MT sessions were completed (80.7% completion rate) with the novel OMPREP outcome measure utilized on 100% of visits. Mean engagement (p<.001), response (p<.001), and pain (p<.001) scores were all significantly greater at evaluation and discharge compared to the lowest observed scores post-HCT.

Conclusion

The novel MT-specific outcome measure, OMPREP, was feasible and demonstrated construct validity when implemented in a pediatric acute-care setting by massage therapists. This new tool may offer a quantitative measure of MT-interventions and assist in tracking patient outcomes.

Are Final Residency Milestones Correlated With Early Fellowship Performance in Pediatrics?

PURPOSE

Milestones have been used to assess trainees across graduate medical education programs and reflect a developmental continuum from novice to expert. This study examined whether residency milestones are correlated with initial fellowship milestone performance in pediatrics.

METHOD

This retrospective cohort study used descriptive statistics to assess milestone scores from pediatric fellows who began fellowship training between July 2017 and July 2020. Milestone scores were obtained at the end of residency (R), middle of the first fellowship year (F1), and end of the first fellowship year (F2).

RESULTS

Data represent 3,592 unique trainees. High composite R scores, much lower F1 scores, and slightly higher F2 scores were found over time for all pediatric subspecialities. R scores were positively correlated with F1 scores (Spearman ρ = 0.12, P < .001) and F2 scores (Spearman ρ = 0.15, P < .001). Although scores are negligibly different when trainees graduate from residency, there were differences in F1 and F2 scores among fellows in different specialties. Those who trained at the same institution for residency and fellowship had higher composite milestone F1 and F2 scores compared with those who trained at different institutions ( P < .001). The strongest associations were between R and F2 scores for the professionalism and communication milestones, although associations were still relatively weak overall (r s = 0.13-0.20).

CONCLUSIONS

This study found high R scores and low F1 and F2 scores across all shared milestones, with weak association of scores within competencies, indicating that milestones are context dependent. Although professionalism and communication milestones had a higher correlation compared with the other competencies, the association was still weak. Residency milestones may be useful for individualized education in early fellowship, but fellowship programs should be cautious about overreliance on R scores due to the weak correlation with F1 and F2 scores.

Description of a Colocated Comprehensive Care Model for People With Sickle Cell and Comorbid Pulmonary Disease

Comorbid pulmonary complications in people with sickle cell disease (pwSCD) are associated with high rates of morbidity and mortality, and poor access to care contributes to poor outcomes among this particularly high-risk pwSCD. Our purpose was to describe the population served and the resources required for hematology, pulmonary, nursing, respiratory therapy, social work, genetics, psychology, and school liaison providers to see these patients in an integrated clinic. We abstracted demographic, medication, clinical, and diagnostics data of the pwSCD seen at least once in this clinic from February 1, 2014 to December 10, 2020 from the electronic medical record and identified 145 unique pwSCD. Abnormal lung function and bronchodilator responsiveness were detected in 31% and 42% of participants respectively. Sleep abnormalities were found in over two-thirds of those screened and 65% had ≥1 previous acute chest syndrome episode. This clinic also allowed for direct provider communication and required relatively limited resources to serve a large number of severely affected pwSCD. Given the degree of abnormal respiratory variables detected and the limited resources required to implement this model, studies are warranted to evaluate whether it has the potential to improve outcomes in high-risk populations.

Venous thromboembolism prophylaxis in sickle cell disease: a multicenter cohort study of adolescent inpatients

Patients with sickle cell disease (SCD) are predisposed to a hypercoagulable state. Despite the increased risk of venous thromboembolism in the SCD population, there is limited evidence available to guide thromboprophylaxis (TP) practices in these patients. This study aimed to assess the use of pharmacologic and nonpharmacologic TP in adolescent patients with SCD using the Pediatric Health Information System (PHIS). We hypothesized that TP was increasingly used in hospitalized adolescent patients with SCD. The study included patients with SCD aged 13 to 21 years, admitted to a PHIS hospital between 1 January, 2010, and 30 June, 2021. A total of 7202 unique patients consisting of 34 094 unique admissions were included for analyses. Pharmacologic or mechanical TP was used in 2600 (7.6%) admissions, with 3.6% of admissions (n = 1225) receiving pharmacologic prophylaxis and 4.3% (n = 1474) receiving mechanical prophylaxis. Pharmacologic TP increased in use from 1.3% of admissions in 2010 to 14.4% in the first half of 2021. Enoxaparin was the most commonly prescribed anticoagulant, used in 87% of admissions in which pharmacologic TP was used. The use of prophylactic direct oral anticoagulants was first documented in 2018 and increased to 25% of admissions with pharmacologic TP by 2021. This study demonstrates a steady increase in TP use in adolescent patients with SCD admitted to the hospital. Prospective cohort studies are needed to determine VTE risk factors in adolescents and children with SCD and the efficacy and safety of prophylactic regimens.

Prevalence and risk factors for pulmonary embolism in children with sickle cell disease: an institutional retrospective cohort study

The study was conducted to examine prevalence of pulmonary embolism in children with sickle cell disease (SCD) and identify potential risk factors associated with pulmonary embolism in a single tertiary paediatric centre. Children with SCD between 0 and 21 years of age from January 2010 to January 2021 were included. Pulmonary embolism was initially identified using International Classification of Diseases (ICD)-9 or 10 codes and confirmed with manual chart review of identified cases. Logistic regression analysis was performed to assess association between SCD specific and general thrombotic risk factors and pulmonary embolism. We identified 492 unique patients with SCD with a median age of 11 years (interquartile range: 4-18). A total of eight (1.6%) patients developed a pulmonary embolism. Patients with pulmonary embolism were significantly older (median, interquartile range: 20.5, 14-21 years) than patients without pulmonary embolism (median, interquartile range: 10, 4-17 years). Central nervous system (CNS) vasculopathy and erythrocytapheresis were significantly associated with pulmonary embolism on univariable logistic regression analysis. A previous diagnosis of deep vein thrombosis (DVT) was significantly more common among patients with pulmonary embolism than among those without pulmonary embolism (50 vs. 5.2%; P < 0.0001). Prevalence of pulmonary embolism in children with SCD was high. Risk factors associated with pulmonary embolism in this study such as CNS vasculopathy or erythrocytapheresis could suggest that the risk for pulmonary embolism in SCD may be related to the severity of disease state. Future studies are needed on pulmonary embolism prevention strategies.

Closing knowledge gaps among parents of children with sickle cell trait

BACKGROUND

Despite needing to be informed about sickle cell trait (SCT) status to make informed reproductive decisions, more than 80% of adults with SCT, including parents of children with SCT who have a high prevalence of SCT, do not know their status.

PROCEDURE

This was a prospective study of parents who received SCT telephone education from the state department of health and then completed SCTaware, a videoconference-administered SCT education program. The objectives were to evaluate knowledge after telephone education and explore if SCTaware closes knowledge gaps. Participants completed a demographic survey, a health literacy assessment, and reported their SCT status. They completed the Sickle Cell Trait Knowledge Assessment before receiving SCTaware, immediately after, and at follow-up visits; high knowledge was a score of 75% or higher correct.

RESULTS

SCTaware and the initial surveys were completed by 61 parents; 45 completed the 6-month surveys. Only 43% of participants had high SCT knowledge after telephone education; 92% achieved high knowledge immediately after, and 84% continued with high knowledge at 6 months. Most parents reported they were aware of their SCT status after telephone education; 12 changed their response after receiving SCTaware.

CONCLUSIONS

Our findings suggest that over half of parents have low SCT knowledge following telephone education, and many may be unaware of their status. SCTaware closes knowledge gaps, leads to high sustained knowledge, and is a potentially scalable tool. Future studies should refine SCTaware and determine if parents use their knowledge to inform their children and reproductive decisions.

A regional anticoagulation program improves safety and outcomes for both children and adults

BACKGROUND

Evidence-based anticoagulation programs usually serve a local, adult patient population. Here we report outcomes for a regional combined pediatric-adult program.

AIMS

The aims of this study were: (1) Compare the pre- vs. post-implementation quality of therapy (% time in therapeutic range (%TTR) and compliance). (2) Assess anticoagulant-relevant outcomes (bleeding and thrombotic complications).

METHODS

Data were collected for the years 2014-2019. Rosendaal linear interpolation was used to calculate %TTR. Bleeding complications were categorized using ISTH-SSC standard nomenclature and new thrombotic events were reviewed.

RESULTS

The patients were divided into a long-term warfarin group (N = 308), 80.2% of whom had cardiac-related therapeutic indications (median age 24y), and a second group (N = 114) comprised of short-term and non-warfarin long-term anticoagulation (median age 16y). Median %TTR for those on long-term warfarin was 78.9%. The incidence of major and clinically relevant non-major bleeding events was 1.65 and 2.43 /100 person-years of warfarin use, respectively. Thromboembolism (TE) incidence was 0.78/100 patient-years of warfarin use. Neither bleeding nor thrombosis was associated with %TTR (p = 0.48). Anticoagulant indication was the only variable associated with bleeding risk (p = 0.005). The second group had no on-therapy TE events but 7.9% experienced bleeding. Complete data were available for a randomly sampled pre-program warfarin group (N = 26). Median %TTR improved from 17.5 to 87% pre- vs. post-implementation. Similarly, compliance (defined as ≥ 1 INR/month) improved by 34.3%.

CONCLUSIONS

In conclusion, this program significantly improved and sustained %TTR and compliance. The lack of association between bleeding and thrombosis events and %TTR may be related to the high median %TTR (> 70%) achieved by this approach.

Outcomes of a radiation sparing approach in medulloblastoma by subgroup in young children: an institutional review

OBJECTIVE

To describe disease outcomes including overall survival and relapse patterns by subgroup in young pediatric patients treated for medulloblastoma with a radiation-sparing approach.

METHODS

Retrospective analysis of clinical outcomes includes treatment, relapse, and salvage therapy and late effects in children treated for medulloblastoma with a radiation-sparing approach at British Columbia Children's Hospital (BCCH) between 2000 and 2020.

RESULTS

There were 30 patients (median age 2.8 years, 60% male) treated for medulloblastoma with a radiation-sparing approach at BCCH. Subgroups included Sonic Hedgehog (SHH) (n = 14), group 3 (n = 7), group 4 (n = 6), and indeterminate status (n = 3). Three- and 5-year event-free survival (EFS) were 49.0% (30.2-65.4%) and 42.0% (24.2-58.9%) and overall survival (OS) 66.0% (95% CI 46.0-80.1%) and 62.5% (95% CI 42.5 and 77.2%), respectively, with a median follow-up of 9.5 years. Relapse occurred in 12/25 patients following a complete response, of whom six (group 4: n = 4; group 3: n = 1; unknown: n = 1) were successfully salvaged with craniospinal axis (CSA) RT and remain alive at a median follow-up of 7 years. Disease/treatment-related morbidity included endocrinopathies (n = 8), hearing loss n = 16), and neurocognitive abnormalities (n = 9).

CONCLUSIONS

This radiation sparing treatment approach for young patients with medulloblastoma resulted in a durable cure in most patients with SHH subgroup medulloblastoma. In those patients with groups 3 and 4 medulloblastoma, relapse rates were high; however, most group 4 patients were salvaged with RT.

Impact of SERPINC1 mutation on thrombotic phenotype in children with congenital antithrombin deficiency-first analysis of the International Society on Thrombosis and Haemostasis pediatric antithrombin deficiency database and biorepository

BACKGROUND

The natural history and genotype-phenotype correlation of congenital antithrombin (AT) deficiency in children are unknown.

OBJECTIVES

To describe the clinical presentation of congenital AT deficiency in children and evaluate its correlation to specific mutations in SERPINC1.

METHODS

In 2017, a prospective pediatric database and DNA biorepository for congenital AT deficiency was established. During the pilot phase, the database was opened at 4 tertiary care centers in Canada and US. Approval from research ethics board was obtained at each participating center. Written consent/assent was obtained from guardians/subjects who met eligibility. Demographic/clinical data were uploaded into a database. DNA extraction and SERPINC1 sequencing were centralized for US centers. Standard statistical methods were used to summarize parameters. Probability of VTE-free survival was assessed using the Kaplan-Meier method.

RESULTS

Overall, 43 participants (25 females) from 31 unique kindreds were enrolled. Median age (range) at enrollment was 14.8 years (1-21 years). Median AT activity was 52% (24%-87%), and median AT antigen (n = 20) was 55% (38%-110%). Nineteen (44%) participants had a history of venous thromboembolism (VTE). Median age at VTE diagnosis was 12.8 years (0.1-19.2 years). SERPINC1 sequencing was completed for 31 participants and 21 unique mutations were identified, including 5 novel variants. Probability of 5-year VTE-free survival (95% CI) for carriers of missense mutations (92.0% [95% CI: 71.6%-97.9%]) was significantly higher compared with carriers of null mutations (66.7% [95% CI: 19.5%-90.4%]); p = .0012.

CONCLUSION

To our knowledge, this is the first pediatric study to document a severe thrombotic phenotype in carriers of null mutations in SERPINC1, when compared with carriers of missense mutations; underscoring the importance of genetic testing.

Prevalence and Risk Factors for Pulmonary Embolism in Pediatric Sickle Cell Disease: A National Administrative Database Study

Patients with sickle cell disease (SCD) have a high risk for venous thromboembolism which is associated with increased risk of mortality. Studies examining risk of pulmonary embolism (PE) in children with SCD are lacking. This study was conducted in children with SCD between 0-21 years of age using a nationwide administrative database in the United States- Pediatric Health Information System (PHIS) from January 2010 to June 2021. Diagnostic codes and imaging, procedure, and pharmaceutical billing codes were used to identify PE and potential clinical, demographic, and utilization risk factors. Logistic regression analyses were performed to assess association between risk factors and PE. We identified 22,631 unique patients with SCD with a median age of 10.8 years (range: <0.1-20.9). A total of 120 (0.53%) patients developed a PE with median age of 17.4 years (range: 6.6-20.9) at PE diagnosis. Patients with PE had longer hospitalization and more frequent ICU admissions than patients without PE (p < 0.001). Risk factors significantly associated with PE on multivariable analysis included older age, prior history of central venous line (CVL), acute chest syndrome, and apheresis. Mortality was not significantly different between those with and without PE. The prevalence of PE in hospitalized children with SCD was estimated to be 0.53%. Patients with PE had higher healthcare utilization characteristics. Factors significantly associated with PE suggest that the risk for PE in SCD may be related to the severity of disease state. Future trials are needed for risk stratification and PE prevention strategies in children with SCD.

BIOM-49. A PILOT STUDY OF CEREBROSPINAL FLUID EXOSOMAL SMALL RNA-SEQUENCING IN PEDIATRIC MEDULLOBLASTOMA PATIENTS ON THE NEXT CONSORTIUM “HEAD START” 4 PROTOCOL

BACKGROUND

Head Start 4 is a randomized clinical trial to determine whether dose-intensive tandem consolidation, compared with a single cycle, with autologous hematopoietic progenitor cell rescue provides a survival benefit in pediatric patients with medulloblastoma or other embryonal tumors. The trial incorporates upfront molecular subgrouping and non-mandatory, prospective blood and cerebrospinal fluid (CSF) collection. This pilot study aimed to identify exosomal non-coding RNAs (exo-ncRNAs) that might serve as novel diagnostic and/or treatment response biomarkers.

METHODS

CSF(1-2mLs) from 11 controls (non-tumor) and 27 medulloblastoma participants including 23 obtained at baseline, 22 at the end of induction, 3 post-consolidation, and 4 relapse time points, were profiled. Exosome isolation and small RNA-sequencing were performed by System Biosciences. Differential gene expression (DGE) was performed in R (DESeq2). Variations in gene expression profiles between samples were visualized using principal component analysis.

RESULTS

After limiting to ncRNAs with expression of 2 counts per million in 50% or more of the samples in each comparison, ~9,500 ncRNAs were detected. DGE analyses revealed 118 ncRNAs with log2 fold change(FC) &gt;2 and 1 ncRNA with log2FC&lt; -2 in baseline CSF samples compared to controls. In contrast, 11 ncRNAs(log2FC &gt;2) and 1 ncRNA(log2FC&lt; -2) were detected in end of induction CSF samples compared to controls. Comparing end of induction to baseline CSF samples accounting for paired samples, 0 ncRNAs(log2FC &gt;2) and 52 ncRNAs(log2FC&lt; -2) were detected.

CONCLUSIONS

Overall, our data indicate that exosomal small RNA-sequencing of limited CSF volumes is feasible. Differential expression and distinct clustering between tumor baseline samples compared to non-tumor controls was observed. CSF-derived exo-ncRNAs at end of induction also demonstrated “normalization” of ncRNA profiles, signifying CSF biomarkers may serve a role in diagnosis and molecular response assessment. A comprehensive analysis including multi-marker predictive model development and molecular subgrouping will be undertaken at completion of study enrollment.

Incidence and Management of Pleural Effusions in Patients with Wilms Tumor: A Pediatric Surgical Oncology Research Collaborative Study

Wilms tumor (WT) is the most common renal malignancy in children. Children with favorable histology WT achieve survival rates of over 90%. Twelve percent of patients present with metastatic disease, most commonly to the lungs. The presence of a pleural effusion at the time of diagnosis of WT may be noted on staging imaging; however, minimal data exist regarding the significance and prognostic importance of this finding. The objectives of this study are to identify the incidence of pleural effusions in patients with WT, and to determine the potential impact on oncologic outcomes. A multi-institutional retrospective review was performed from January 2009 to December 2019, including children with WT and a pleural effusion on diagnostic imaging treated at Pediatric Surgical Oncology Research Collaborative (PSORC) participating institutions. Of 1,259 children with a new WT diagnosis, 94 (7.5%) had a pleural effusion. Patients with a pleural effusion were older than those without (median 4.3 vs 3.5 years; p=0.004), and advanced stages were more common (local stage III 85.9% vs 51.9%; p<0.0001). Only 14 patients underwent a thoracentesis for fluid evaluation; 3 had cytopathologic evidence of malignant cells. Event-free and overall survival of all children with WT and pleural effusions was 86.2% and 91.5%, respectively. The rate and significance of malignant cells present in pleural fluid is unknown due to low incidence of cytopathologic analysis in our cohort; therefore, the presence of an effusion does not appear to necessitate a change in therapy. Excellent survival can be expected with current stage-specific treatment regimens.

LTBK-05. Outcomes of Infants and Young Children with Newly Diagnosed Localized (M0) SHH Medulloblastoma Treated on The NEXT Consortium “Head Start” 4 Protocol

Advances in RNA and DNA profiling have identified four core molecular subgroups of medulloblastoma of prognostic significance: Sonic Hedgehog (SHH) subtype, WNT subtype, Group 3, and Group 4. Infants and young children with SHH medulloblastoma have demonstrated a favorable outcome in clinical trials utilizing either high-dose chemotherapy (“Head Start”) or a combination of intravenous and intraventricular methotrexate (HIT-SKK). Two recently conducted clinical trials (COG ACNS1221 and St. Jude – SJYC07) failed to demonstrate similar survival advantage with conventional dose chemotherapy and without intraventricular methotrexate. “Head Start” 4 (HS 4) is a prospective randomized clinical trial that tailors treatment based on medulloblastoma molecular subgroups and response to induction chemotherapy to compare the efficacy of one versus versus three (tandem) cycles of myeloablative therapy. Eligibility includes newly diagnosed children less than six years of age with localized medulloblastoma. Eligible patients with SHH medulloblastoma were considered “low-risk” and non-randomly assigned to receive three cycles of induction chemotherapy (vincristine, cisplatin, cyclophosphamide, etoposide, and high-dose methotrexate) followed by consolidation with single cycle of myeloablative chemotherapy (thiotepa, carboplatin, etoposide) and autologous hematopoietic progenitor cell rescue. Patients with less than a complete response after three induction cycles received two additional cycles prior to consolidation therapy. Only children between 6 -10 years old, or those with confirmed residual tumor post-consolidation, were meant to receive irradiation after consolidation. Twenty-eight children with localized SHH medulloblastoma were enrolled on the trial with a median age of 2.1 years (range: 0.3-5.9 years). Median follow-up for this cohort is 29.6 months (range: 7.0-58.6 months). The estimated 3-year event-free (EFS) and overall survival (OS) is 96% (CI: 89-100%) and 100%, respectively. The estimated 3-year EFS for SHH subtype 1 and 2 patients is 100% and 95%, respectively (p=0.65). None of the M0 SHH medulloblastoma patients received irradiation.

EPCT-05. Phase Ib study of unesbulin (PTC596) in children with newly diagnosed diffuse intrinsic pontine glioma (DIPG) and high-grade glioma (HGG): A report from the COllaborative Network for NEuro-Oncology Clinical Trials (CONNECT)

BACKGROUND: The B-cell-specific Moloney murine leukemia virus integration site-1 (BMI-1) protein, implicated in self-renewal and DNA-damage signaling, is highly expressed in DIPG and HGG. Preclinically, BMI-1 modulation by unesbulin (PTC596 [which mediates hyperphosphorylation and subsequent degradation of BMI-1]) leads to DIPG/HGG cell proliferation blockade, mitotic abnormalities, and tumor cell sensitization to radiation-induced DNA damage. METHODS: This phase Ib study sought to determine the maximally tolerated dose/ recommended phase 2 dose (RP2D) of unesbulin administered concurrently with radiotherapy and adjuvantly in children with newly diagnosed DIPG or HGG. Patients were enrolled according to a Rolling-6 design and received oral unesbulin twice weekly during radiotherapy and as maintenance therapy. RESULTS: Twenty-seven patients enrolled (median age: 8.5 years [range: 2-18]), including 18 patients with DIPG and nine patients with HGG. Unesbulin was administered in capsule formulation in the first nine patients, then tablet formulation for subsequent patients. Within the capsule formulation group, three dose-limiting toxicities (DLTs) were observed in two patients on dose level 2 (grade 4 neutropenia). Within the tablet formulation group, four DLTs were experienced by three patients on dose level 2 (grade 3 ALT elevation, grade 3 dehydration/vomiting, grade 3 decreased ejection fraction, grade 4 neutropenia). Dose level 1 was declared the RP2D, and six additional patients enrolled in the expansion cohort at this dose without DLTs. Most common drug-related grade 3/4 toxicities were neutropenia (48%), leucopenia (35%), and elevated ALT (26%). Similar pharmacokinetic profiles were observed for capsule and tablet formulations, consistent with adult data. Survival outcomes and genomics results will be shared at time of presentation. CONCLUSIONS: The RP2D of unesbulin in children newly diagnosed with DIPG or HGG is 200mg/m2 twice weekly, concurrent with and following radiotherapy. The recently opened surgical cohort will assess intratumoral pharmacokinetics and inhibition of tumor BMI-1 signaling, with results forthcoming.

EPCT-06. Phase I study of ribociclib and everolimus post-radiotherapy in children with newly diagnosed diffuse intrinsic pontine glioma (DIPG) and high-grade glioma (HGG): Updated report from the COllaborative Network for NEuro-Oncology Clinical Trials (CONNECT)

BACKGROUND: Dual inhibition of CDK4/6 and mTOR in DIPG and pediatric HGG has strong biologic rationale, given prevalent genetic alterations resulting in upregulated cell cycle and PI3K/mTOR pathways in these diseases, as well as non-overlapping agent toxicities. This study sought to evaluate safety/tolerability and determine the recommended phase 2 dose (RP2D) of ribociclib and everolimus among children with newly diagnosed DIPG and HGG post-radiotherapy. METHODS: Patients were enrolled according to a Rolling-6 design and received oral ribociclib and everolimus once daily for 21 and 28 days, respectively, starting 2-4 weeks post-completion of radiotherapy. All HGG and biopsied DIPG patients were screened for RB protein presence by immunohistochemistry. Pharmacokinetics and survival data were analyzed.

RESULTS: Nineteen patients enrolled (median age: 8 years [range: 2-18]). Three patients enrolled at each of dose levels 1 and 2 without dose-limiting toxicities (DLTs). Thirteen patients enrolled at dose level 3, with one patient experiencing a DLT (grade 3 infection). One patient came off therapy prior to cycle 9 due to cardiac toxicity. The most common grade 3/4 toxicities were neutropenia (33%), leucopenia (17%), and lymphopenia (11%). Steady-state everolimus exposures in combination were 1.9±0.9-fold higher than single-agent administration. Median overall survival (OS) for 15 patients with DIPG was 13.9 months, with 12-, 24-, and 36-month OS of 53.3%, 38.9%, and 38.9%. Median event-free survival for four patients with HGG was 10.5 months. Among patients with tumor molecular profiling, two longer survivors (OS: 20, &gt;37 months) had evidence of cell cycle upregulation with CDKN2A/B deletion and CDK4 overexpression identified. CONCLUSIONS: The combination of ribociclib and everolimus was well-tolerated post-radiotherapy in children with newly diagnosed DIPG and HGG, with a RP2D of ribociclib 170 mg/m2 days 1-21 and everolimus 1.5 mg/m2 days 1-28. Results will inform a molecularly-guided phase II study currently underway to evaluate efficacy.

Impact of hydroxyurea dose and adherence on hematologic outcomes for children with sickle cell anemia

BACKGROUND

Hydroxyurea is the primary treatment for sickle cell anemia (SCA), yet real-world implementation in high-income settings is suboptimal. Variation in prescribed hydroxyurea dose and patient adherence in these settings can both affect actual exposure to hydroxyurea. Quantifying the contributions of hydroxyurea dose and medication adherence to the relationship between hydroxyurea exposure and hematologic parameters could inform strategies to optimize exposure and improve outcomes.

PROCEDURE

We evaluated the relationship between hydroxyurea exposure, defined by average prescribed dose and adherence, and hematologic parameters using data from children with SCA who were enrolled in two prospective hydroxyurea adherence studies. Hydroxyurea adherence was assessed by video directly observed therapy or electronic pill bottle and medication administration record. Average prescribed dose was abstracted from prescriptions in patients' electronic medical record. Participants with a hydroxyurea exposure >20 mg/kg/day and ≤20 mg/kg/day were included in the higher and lower exposure groups, respectively.

RESULTS

Forty-five participants were included in the analysis (56% male; median age 12 years [range 2-19]; 98% Black). Higher exposed participants (n = 23) were prescribed a higher dose (27.2 vs. 24.4 mg/kg/day, p = .002) and had better adherence (0.92 vs. 0.71, p ≤ .001) compared to lower exposed participants (n = 22). Higher exposure was associated with higher fetal hemoglobin (p = .04) and mean corpuscular volume (p = .02).

CONCLUSIONS

Higher hydroxyurea exposure is associated with improved hematologic parameters in the high-income setting and is affected by both prescribed dose and adherence. Future studies are needed to optimize both adherence and hydroxyurea prescribing and confirm that increasing exposure improves clinical outcomes in this setting.

Phase I study of ribociclib and everolimus in children with newly diagnosed DIPG and high-grade glioma: A CONNECT pediatric neuro-oncology consortium report

Background

Genomic aberrations in the cell cycle and PI3K/Akt/mTOR pathways have been reported in diffuse intrinsic pontine glioma (DIPG) and high-grade glioma (HGG). Dual inhibition of CDK4/6 and mTOR has biologic rationale and minimal overlapping toxicities. This study determined the recommended phase 2 dose (RP2D) of ribociclib and everolimus following radiotherapy in children with DIPG and HGG.

Methods

Patients were enrolled according to a Rolling-6 design and received ribociclib and everolimus once daily for 21 and 28 days, respectively. All patients with HGG and biopsied DIPG were screened for retinoblastoma protein presence by immunohistochemistry. Pharmacokinetics were analyzed.

Results

Nineteen patients enrolled (median age: 8 years [range: 2-18]). Three patients enrolled at each dose level 1 and 2 without dose-limiting toxicities (DLT). Thirteen patients were enrolled at dose level 3, with one patient experiencing a DLT (grade 3 infection). One patient came off therapy before cycle 9 due to cardiac toxicity. The most common grade 3/4 toxicities were neutropenia (33%), leucopenia (17%), and lymphopenia (11%). Steady-state everolimus exposures in combination were 1.9 ± 0.9-fold higher than single-agent administration. Median overall survival for 15 patients with DIPG was 13.9 months; median event-free survival for four patients with HGG was 10.5 months. Two longer survivors had tumor molecular profiling identifying CDKN2A/B deletion and CDK4 overexpression.

Conclusion

The combination of ribociclib and everolimus following radiotherapy in children with newly diagnosed DIPG and HGG was well tolerated, with a RP2D of ribociclib 170 mg/m² and everolimus 1.5 mg/m². Results will inform a molecularly guided phase II study underway to evaluate efficacy.

Recurrent Wnt medulloblastoma treated with marrow-ablative chemotherapy and autologous hematopoietic progenitor cell rescue: a dual case report and review of the literature

Wnt-activated medulloblastoma (MB) confers an excellent prognosis. However, specific treatment strategies for patients with relapsed Wnt-MB are unknown. We report two patients with recurrent beta-catenin nucleopositive Wnt-MB successfully treated by incorporating marrow-ablative chemotherapy and autologous hematopoietic progenitor cell rescue (HDCx/AuHPCR). We also present a review of the literature for previously reported cases of relapsed Wnt-MB. We propose that patients with recurrent Wnt-MB may be treated using a multi-disciplinary approach that includes HDCx/AuHPCR with or without re-irradiation.

Andexanet Alfa Versus Prothrombin Complex Concentrates/Blood Products as Apixaban/Rivaroxaban Reversal Agents: A Survey Among Pediatric Hematologists

Direct oral factor Xa inhibitors (DXIs) are approved for use in adult patients with non-valvular heart disease for stroke prevention, and the treatment/prevention of venous thromboembolism (VTE). Recent pediatric clinical trials have demonstrated safety and efficacy of direct oral anticoagulants (DOACs) in the treatment of VTE. However, there is a lack of evidence regarding the use of andexanet alfa and prothrombin complex concentrates (PCC) for anticoagulation reversal of DXIs in the pediatric population. To better understand current DXI reversal strategies in this age group, a 10-question survey was conducted among pediatric hematology members of the Hemostasis and Thrombosis Research Society. Seventeen percent completed the survey (27 of 163 pediatric hematology members) with 74% (n = 20) reporting their use of DXIs for the treatment and prevention of VTE. Forty-four percent (n = 12) would choose andexanet alfa as first-line treatment for life-threatening bleeding while 52% (n = 14) would use PCC first with one individual choosing recombinant factor VII for DXI reversal. Clinical studies of andexanet alfa and PCC for the management of DXI-associated life-threatening bleeding require further investigation in the pediatric population.

Iron deficiency and fatigue among adolescents with bleeding disorders

Iron deficiency anemia is associated with heavy menstrual bleeding (HMB) and, by extension, a bleeding disorder (BD). It is unknown if iron deficiency without anemia is associated with a BD in adolescents. Moreover, the threshold of ferritin associated with fatigue in adolescents with HMB is unclear. In this multicenter study, we enrolled adolescents with HMB without BD. Participants underwent BD and anemia work-up in Young Women's Hematology Clinics and completed the Peds QL™ fatigue scale. BDs were defined as von Willebrand Disease, platelet function defect, clotting factor deficiencies, and hypermobility syndrome. Two hundred and fifty consecutive adolescents were enrolled, of whom 196 met eligibility criteria. Overall, 43% (95% confidence interval: 36%-50%) were diagnosed with BD. A total of 61% (n = 119) had serum ferritin levels < 15 ng/mL, 23.5% (n = 46) had iron deficiency only, and 37% (n = 73) had iron deficiency anemia. Low ferritin or ferritin dichotomized as < 15 or ≥ 15 ng/mL was not associated with BD on univariable analysis (p = .24) or when accounting for age, race, ethnicity, body mass index, and hemoglobin (p = .35). A total of 85% had total fatigue score below the population mean of 80.5, and 52% (n = 102) were > 2 SD (or < 54) below the mean, the cut-off associated with severe fatigue. A ferritin threshold of < 6 ng/mL had a specificity of 79.8% but a sensitivity of 36% for severe fatigue. In conclusion, iron deficiency without anemia is not a predictor of BD in adolescents with HMB in a specialty setting. Severe fatigue, especially sleep fatigue, is prevalent in adolescents with BD. Ferritin of < 6 ng/mL has ~80% specificity for severe fatigue in adolescents with HMB.

BIOM-42. IMMUNOHISTOCHEMICAL ASSESSMENT OF MEMBRANOUS SOMATOSTATIN TYPE 2A RECEPTOR (SST2A) EXPRESSION ACROSS HIGH-RISK PEDIATRIC CENTRAL NERVOUS SYSTEM (CNS) TUMORS

INTRODUCTION

77Lu-DOTATATE, a radionuclide therapy which binds SST2A, has demonstrated efficacy in neuroendocrine tumors and evidence of CNS penetration, supporting potential expansion within pediatric neuro-oncology. Understanding the prevalence of SST2A expression across pediatric CNS tumors is essential to identify patients who may benefit from somatostatin receptor-targeted therapy and to further elucidate the oncogenic role of SST2A.

METHODS

SST2A immunohistochemistry (IHC) was performed on tumor specimens and interpreted by two experienced pathologists (blinded), utilizing semi-quantitative scoring of membranous expression within viable tumor. Immunoreactive cell percentage was visually scored as 0 (none), 1 (&lt; 10%), 2 (10-50%), 3 (51-80%), or 4 (&gt;80%). Staining intensity was scored as 0 (none), 1 (weak), 2 (moderate), or 3 (strong). Combined scores for each specimen were calculated by multiplying percent immunoreactivity and staining intensity values (range=0-12).

RESULTS

A total of 117 tumor samples from 113 patients were analyzed. Significant differences in SST2A IHC scores were observed across histopathologic diagnoses, with consistently high scores in medulloblastoma (mean±SD=7.6±3.6 [n=36]) and meningioma (5.7±3.4 [n=15]), compared to minimal or absent expression in ATRT (0.3±0.6 [n=3]), ETMR (1.0±0 [n=3]), ependymoma (grades I-III; 0.2±0.7 [n=26]), and high-grade glioma (grades III-IV; 0.4±0.7 [n=22]). Pineoblastoma (3.8±1.5 [n=4]) and other embryonal tumors (2.3±3.8 [n=8]) exhibited intermediate, variable expression. Among expressors, there was no association between SST2A IHC score and patient age, sex, presence of metastases, likelihood of relapse, or prior treatment. In a subset of paired primary and recurrent specimens from 3 patients, SST2A IHC scores remained largely unchanged. Among medulloblastomas, SST2A IHC scores were higher in non-SHH (8.6±3.2) than SHH (5.0±3.3) molecular subgroups (p=0.033).

CONCLUSIONS

High membranous SST2A expression was demonstrated in medulloblastoma, meningioma, and some rarer embryonal tumors with potential diagnostic, biologic, and therapeutic implications. Somatostatin receptor-targeted therapy such as 177Lu-DOTATATE deserves further investigation in these highly SST2A-expressing pediatric CNS tumors.

Chemotherapy strategies for young children newly diagnosed with desmoplastic/extensive nodular medulloblastoma up to the era of molecular profiling – a comparative outcomes analysis of prospective multi-center European and North American trials

Aims

Survival has been poor in several multi-center/national trials since the 1980s, either delaying, avoiding or minimizing brain irradiation in young children with medulloblastoma. The introduction of German regimens supplementing “standard” chemotherapy with both intravenous high-dose (HD-MTX) and intraventricular (IVENT-MTX) methotrexate, and North American regimens incorporating marrow-ablative chemotherapy with autologous hematopoietic cell rescue (HDCx+AuHCR), have reported encouraging outcomes. We performed a comparative outcomes analysis of these differing strategies for young children with desmoplastic/extensive nodular medulloblastoma.

Method

Data from 12 trials reported between 2005 and 2020 for children &lt;six-years-old with desmoplastic/extensive nodular medulloblastoma were reviewed; event-free (EFS) survival+/-standard errors were compared.

Results

The German HIT-SKK’92 and HIT-SKK’00 trials incorporating HD-MTX and IVENT-MTX reported 85+/-8% and 95+/-5% 5-10-year EFS respectively; a third trial (ACNS1221) incorporating HIT-SKK therapy but without IVENT-MTX reported only 49+/-10% EFS. Three trials (Head Start I and II combined and CCG-99703) employing induction chemotherapy without HD-MTX, followed by one or three HDCx+AuHCR cycles, reported 3-5-year EFS of 67+/-16% and 79+/-11%. Two trials employing HD-MTX-containing induction chemotherapy (Head Start III and ACNS0334), followed by one or three HDCx+AuHCR cycles, reported 3-5-year EFS of 89+/-6% and 100%, respectively. Finally, four trials utilizing neither IVENT-MTX nor HDCx+AuHCR (UK-CNS-9204, CCG-9921, COG-P9934 and SJYC07) reported 2-5 year EFS of 35+/-11%, 77+/-9%, 58+/-8% and 53+/-9% respectively.

Conclusion

A trend towards better EFS for young children with desmoplastic/extensive nodular medulloblastoma is observed in trials including eitherHD-MTX and IVENT-MTX or including HD-MTX-containing induction chemotherapy and HDCx+AuHCR. Trials excluding HD-MTX, IVENT-MTX and HDCx+AuHCR have poorer outcomes.

Drive-through Anticoagulation Clinic During The COVID-19 Pandemic

An innovative approach to anticoagulation management during the COVID-19 pandemic was used at our center that allowed patients to stay in their vehicle while our anticoagulation advanced practice registered nurse obtained blood for point-of-care international normalized ratio (INR) testing while education and counseling were completed. A significant improvement in the median percentage of INR within the therapeutic range was observed among the patients who used the drive-through clinic. A small group of patients improved compliance to anticoagulation monitoring. Clinical care models, such as this clinic approach may improve patient compliance and adherence to anticoagulation beyond the pandemic needs.

Vitamin D has no impact on outcomes after HSCT in children-A retrospective study

Vitamin D not only plays an important role in bone metabolism but is also involved in multiple immune-mediated processes in the body which may be adversely affected in those with low levels. Most pediatric studies evaluating the association of vitamin D in patients undergoing allogeneic HSCT are single-center studies. We present the results of retrospective study at 5 centers across the United States in pediatric patients undergoing allogeneic HSCT. (VDD) and (VDI) were defined by vitamin D levels of <20 ng/ml and 21-30 ng/ml, respectively. The mean vitamin D levels pre-HSCT, day +30, and +100 were suggestive of VDI, but normalized thereafter. We compared the transplant characteristics and outcomes in 233 patients with VDD and VDI and those with normal levels and found no statistical difference in neutrophil or platelet engraftment, infections (viral, bacterial, or fungal) post-HSCT, length of hospital stay during HSCT, graft failure, acute or chronic GvHD, survival at day +100 and 1 year, or relapse of primary malignancy. We conclude that VDI or deficiency does not affect any of the common transplant variables after allogeneic HSCT in children. There is a need of a large multicenter prospective study to evaluate its role further.

Pediatric adaptions are needed to improve the diagnostic accuracy of thyroid ultrasound using TI-RADS

BACKGROUND/PURPOSE

Thyroid Imaging Reporting and Data System (TI-RADS) is validated in adults but not yet in children. The purpose of this study was to determine the sensitivity, specificity, and accuracy of TI-RADS in predicting thyroid malignancy for pediatric nodules, and to compare the diagnostic accuracy to the current American Thyroid Association (ATA) guidelines.

METHODS

A single institution retrospective review was performed of patients younger than 21 years who underwent thyroid nodule fine needle aspiration biopsy (FNAB). Two radiologists were blinded to the pathology and independently classified all biopsied thyroid nodules based on TI-RADS. ATA and TI-RADS guidelines were analyzed to determine the diagnostic sensitivity and specificity of both scoring systems.

RESULTS

115 patients (median age 15.5 years, 90 females) with 138 nodules were scored using TI-RADS. There was moderate inter-rater agreement between radiologists (Kappa = 0.51; p < 0.0001). Evaluating several potential TI-RADS criteria, 23.2%-68.1% of nodules were recommended for FNAB, compared to 82.6% of nodules using ATA guidelines. Using TI-RADS ≥ 3 (without size cutoff) as an indication for FNAB had 100% sensitivity with no missed suspicious or malignant nodules on cytology or pathology.

CONCLUSIONS

Using TI-RADS for diagnostic management of pediatric thyroid nodules improves accuracy in predicting malignancy.

Unfractionated heparin using actual body weight without dose capping in obese pediatric patients-Subgroup analysis from an observational cohort study

To evaluate the correlation between an uncapped, actual body weight-based unfractionated heparin dosing strategy, we performed a body mass index-based subanalysis of a previously reported pediatric cohort. Nearly half (45%) of obese patients were supra-therapeutic on initial anti-FXa assessment. Obese patients achieved therapeutic anti-FXa significantly faster than nonobese patients (median 4 vs 12 hours, P = .0192) and were more likely to have any supra-therapeutic anti-FXa levels (77% vs 35%; P = .0021). There was no statistically significant difference in major or clinically relevant nonmajor bleeding rates between weight categories (P = .69). Prospective pediatric studies are warranted to confirm our findings.

Supportive care and osteopathic medicine in pediatric oncology: perspectives of current oncology clinicians, caregivers, and patients

BACKGROUND AND OBJECTIVE

Many children receiving chemotherapy struggle with therapy-induced side effects. To date, there has been no literature investigating the needs, knowledge, or implementation of osteopathic manipulative treatments (OMT) as a supportive care option in pediatric oncology. We hypothesized that pediatric oncology clinicians, caregivers, and patients have (a) limited knowledge of OMT and (b) dissatisfaction with current supportive care options and (c) would be interested in having OMT available during chemotherapy, once educated.

METHODS

Participants included three cohorts: (1) children aged ≥ 9 years, diagnosed with cancer and actively receiving chemotherapy; (2) their caregivers; and (3) oncology clinicians at Nationwide Children's Hospital. Participants completed 1:1 semi-structured interviews, which were audio-recorded, transcribed, and analyzed for thematic content regarding their perception of supportive care measures and views on OMT. Quantitative data was summarized descriptively.

RESULTS

A total of 60 participants completed the interview. Participants demonstrated limited awareness of osteopathic medicine; no participant had more than "some" knowledge of OMT. After education about OMT using a brief video, all clinicians, caregivers, and 95% of patients were receptive to OMT as a supportive care option. Major themes included the following: (a) patients have uncontrolled chemotherapy side effects, (b) improved supportive care options are desired, and (c) osteopathic medicine is a favorable supportive care adjunct.

CONCLUSIONS

Pediatric oncology clinicians, caregivers, and patients reported a need for better management of chemotherapy-associated side effects and an interest in utilizing OMT. These findings support further investigation into the safety, feasibility, and efficacy of implementing OMT in the pediatric oncology clinical setting.

Impact of a Best Practice Prevention Bundle on Central Line-associated Bloodstream Infection (CLABSI) Rates and Outcomes in Pediatric Hematology, Oncology, and Hematopoietic Cell Transplantation Patients in Inpatient and Ambulatory Settings

BACKGROUND

Pediatric hematology, oncology, and hematopoietic cell transplantation (HCT) patients are at increased risk for bloodstream infections. The authors sought to evaluate the influence of a standardized best practice central venous catheter (CVC) maintenance bundle on the burden of and risk factors for mucosal barrier injury (MBI) and non-MBI central line-associated bloodstream infections (CLABSIs) across a common inpatient and ambulatory continuum in this high-risk population.

METHODS

A retrospective cohort study of patients with underlying malignancy, hematologic disorders, and HCT recipients with a CVC in place at the time of CLABSI diagnosis in both inpatient and ambulatory settings from January 1, 2012 to December 31, 2016. Descriptive, nonparametric statistics were used to describe patient characteristics and outcomes. Logistic regression analyses were applied to identify potential risk factors for inpatient versus ambulatory and MBI versus non-MBI CLABSI.

RESULTS

During the 5-year period, 118 of 808 (14.6%) patients had 159 laboratory-confirmed CLABSIs for ambulatory and inpatient CLABSI rates of 0.27 CLABSI/1000 and 2.2 CLABSI/1000 CVC days, respectively. CLABSI occurred more frequently in hospitalized patients after HCT and with underlying leukemia, most frequently caused by Gram-negative bacteria. MBI CLABSI accounted for 42% of all CLABSI with a 3-fold higher risk in hospitalized patients. Having multiple CVC or a CVC that was not a port independently associated with higher CLABSI risk.

CONCLUSIONS

In our cohort, non-MBI CLABSI continued to account for the majority of CLABSI. CVC type is independently associated with higher overall CLABSI risk. Further studies are needed to reliably define additional prevention strategies when CLABSI maintenance bundles elements are optimized in this high-risk population.

MBCL-19. CHEMOTHERAPY STRATEGIES FOR YOUNG CHILDREN NEWLY DIAGNOSED WITH DESMOPLASTIC/EXTENSIVE NODULAR MEDULLOBLASTOMA UP TO THE ERA OF MOLECULAR PROFILING – A COMPARATIVE OUTCOMES ANALYSIS OF PROSPECTIVE MULTI-CENTER EUROPEAN AND NORTH AMERICAN TRIALS

BACKGROUND/OBJECTIVE

Survival has been poor in several multi-center/national trials since the 1980s, either delaying, avoiding or minimizing brain irradiation in young children with medulloblastoma. The introduction of German regimens incorporating both intravenous high-dose (HD-MTX) and intraventricular (IVENT-MTX) methotrexate, and North American regimens utilizing marrow-ablative chemotherapy with autologous hematopoietic cell rescue (HDCx+AuHCR), have reported encouraging outcomes. We performed a comparative outcomes analysis of these strategies for young children with desmoplastic/extensive nodular medulloblastoma (D/ENMB).

DESIGN/METHODS

Data from 12 trials reported between 2005 and 2019 for children &lt;six-years-old with D/ENMB were reviewed; event-free (EFS) with standard errors were compared.

RESULTS

The German HIT-SKK’92 and HIT-SKK’00 trials incorporating HD-MTX and IVENT-MTX reported 85+/-8% and 95+/-5% 5-10-year EFS respectively; a third trial (ACNS1221) incorporating HIT-SKK therapy but without IVENT-MTX reported 49+/-10% EFS. Three trials (Head Start I/II combined and CCG-99703) employing induction chemotherapy without HD-MTX, followed by 1/3 HDCx+AuHCR cycles, reported 3-5-year EFS of 67+/-16% and 79+/-11%. Two trials employing HD-MTX-containing induction chemotherapy (Head Start III and ACNS0334), followed by 1/3 HDCx+AuHCR cycles, reported 3-5-year EFS of 89+/-6% and 100%, respectively. Finally, four trials utilizing neither IVENT-MTX nor HDCx+AuHCR (UK-CNS-9204, CCG-9921, COG-P9934 and SJYC07) reported 2-5-year EFS of 35+/-11%, 77+/-9%, 58+/-8% and 53+/-9%.

CONCLUSIONS

A trend towards better EFS for young children with D/ENMB is observed in trials including either HD-MTX as well as IVENT-MTX or including HD-MTX-containing induction chemotherapy and HDCx+AuHCR. Trials excluding HD-MTX, IVENT-MTX and HDCx+AuHCR have poorer outcomes.

MBCL-23. PRELIMINARY ANALYSIS OF TREATMENT-RELATED TOXICITIES DURING INDUCTION CHEMOTHERAPY FOR PATIENTS ON THE HEAD START 4 TRIAL

The currently active, prospective multi-center Head Start 4 (HS4) trial for CNS embryonal tumors differs from prior HS I-III trials by utilizing absolute phagocyte count (APC) as a measure of myeloid recovery instead of absolute neutrophil count. The aim of this study was to determine if utilization of APC resulted in unanticipated treatment-related toxicities during induction chemotherapy for patients enrolled on HS4. Review of the RedCap database was conducted for treatment-related CTCAE grade 3 and 4 toxicities. Data were summarized descriptively. Nonparametric statistical methods were used for comparisons. At the time of this most recent analysis, a total of 180 induction cycles were completed for the 57 patients enrolled. Of the 57 patients, nine voluntarily discontinued therapy after completing a median of three cycles each. These patients had a higher number of documented infections (59% versus 24%, p=0.0004). Veno-occlusive disease (VOD) occurred in five patients, three of whom voluntarily discontinued therapy. Since the protocol amendment utilizing milligram per kilogram dosing for patients less than six years of age, there have been no documented episodes of VOD. The overall toxicities for this cohort were comparable to those reported for induction chemotherapy in HS I-II trials. The toxic death rate is lower for HS4 compared to HS I-II (0.018% versus 4.7–6%) (Chi et al 2004). Other than the high rate of infection, possibly associated with shorter duration of the immediately prior cycles, the use of APC as part of a dose-compression strategy in HS4 does not appear associated with more significant toxicities.

GCT-23. MULTI-INSTITUTIONAL ANALYSIS OF TREATMENT MODALITIES IN BASAL GANGLIA AND THALAMIC GERMINOMA

BACKGROUND

Central nervous system (CNS) germinomas are radiotherapy (RT)-sensitive tumors with excellent survival. Current treatment strategies combine chemotherapy with RT to reduce the field and dose of RT. There is no standard treatment for germinomas originating in the basal ganglia/thalami (BGTG) given their rarity and poorly-defined imaging characteristics. Craniospinal (CSI), whole brain (WBI), whole ventricle (WVI), and focal RT have been previously utilized; however, the optimal strategy remains unclear.

METHODS

Retrospective multi-institutional analysis was conducted across 18 institutions in four countries.

RESULTS

For 46 cases with non-metastatic BGTG, the event-free survival (EFS) was 86.9% at both 5 and 10 years, while overall survival (OS) was 100%, and 95.7% respectively at 5 and 10 years. Median RT dose and range for the various treatment volumes were as follows: CSI (n=10): 2340 cGy (1980–3060 cGy), WBI (n=8): 2340 (1800–3000 cGy), WVI (n=14): 2340 cGy (1800–2550 cGy), focal (n=9): 3600 cGy (3060–5400 cGy). There was no statistically significant difference in the EFS based on RT modality (p=0.57), but EFS for subjects with CSI and WBI were both 100%. The three subjects who received chemotherapy alone had significantly lower EFS than those who received chemotherapy and RT (p=0.001), but were salvageable with RT.

CONCLUSION

In the largest study to date for BGTG, there were no significant differences in outcomes between patients who received CSI, WBI, WVI or focal RT. This group of patients should be included in future prospective clinical trials, and a more limited RT field may be considered.

Evaluating Perspectives of a Smartphone Medication Application in the Adolescent and Young Adult Oncology Population: A Qualitative Study

Purpose: Medication adherence research involving adolescent and young adult (AYA) oncology patients has consisted of small, retrospective studies demonstrating poor adherence rates. Technology plays an active role in attempt to improve medication adherence. There is a growing body of literature investigating the role of smartphone applications (apps). We hypothesized a medication phone app, MedActionPlan Pro (MPP), leads to perceived improvement in medication adherence. Methods: Thirty AYA oncology patients actively receiving treatment (AYA defined as 15-30 years) at Nationwide Children's Hospital were enrolled. Participants downloaded the MPP app on their smartphone for 3 months, during which time participants were provided text messages and alerts to encourage medication adherence. Post-app use, participants completed semi-structured interviews. Interviews were audio-recorded, transcribed, and independently coded to determine consensus thematic content. Results: Thirty AYA oncology participants (16 male), median age 17.5 (range: 15-30 years), participated in the study, with 22 participants (55% male) with a median age of 18 years (range: 15-30 years) participated in the final qualitative survey interview. Participants reported positive views about app utilization and perceived improved medication adherence. Additional themes included perceived decreased forgetfulness, improved organization, and identified customization for medications within the app was most important to AYAs. Conclusion: AYA oncology patients reported improvement in perceived medication adherence utilizing MPP and identified several features they thought would lead to improved medication adherence. These findings, integrated with previous literature, support the further need to investigate the utility of medication adherence apps that fit the unique needs of AYA oncology patients.

Measuring hydroxyurea adherence by pharmacy and laboratory data compared with video observation in children with sickle cell disease

BACKGROUND

Hydroxyurea nonadherence is common among children with sickle cell disease (SCD), but it is unclear if current adherence measures are valid compared with video directly observed therapy (VDOT), a reference method. The objectives were to evaluate if hydroxyurea adherence by pharmacy records, urine assay, mean corpuscular volume (MCV), and/or fetal hemoglobin (HbF) correlated with and was sensitive and specific compared with VDOT.

METHODS

This was a cross-sectional analysis of adherence data from 34 children with SCD on a single-arm, six-month hydroxyurea adherence study. Spearman correlation coefficient compared participants' adherence by pharmacy records, MCV, and HbF to adherence by VDOT. The sensitivity and specificity of ≥80% adherence by pharmacy records, two urine samples with hydroxyurea, MCV ≥100 fl/L, and HbF ≥20% compared with ≥80% VDOT adherence were also calculated.

RESULTS

Median pharmacy and VDOT adherence rates were similar (87.8% vs 88.1%, P = 0.75) and mildly correlated (r_s  = 0.45; P = 0.008) but the sensitivity of ≥80% adherence by pharmacy records was 72.7% and specificity was 45.5%. MCV (r_s  = -0.02, P = 0.92) and HbF (r_s  = -0.2, P = 0.33) did not significantly correlate with VDOT adherence. Sensitivity and specificity were 83.3% and 33.3% for having two urine samples with hydroxyurea, 35% and 71.4% for MCV ≥100 fl/L, and 75% and 0% for HbF ≥20%, respectively.

CONCLUSIONS

Commonly used tools to measure hydroxyurea adherence may not correlate with or be valid compared with video adherence. Future studies to refine these measures are needed to effectively target adherence interventions to children with SCD who have the potential to benefit. (ClinicalTrials.gov NCT02578017).

Catheter-directed thrombolysis for submassive pulmonary embolism in children: A case series

Incidence of venous thromboembolism, including pulmonary embolism (PE), continues to rise in children. Optimum management of submassive PE is unclear. The principal objective of this retrospective study was to investigate the radiological and clinical outcomes in children with submassive PE treated with catheter-directed thrombolysis (CDT). Five patients underwent six episodes of CDT. No patient developed major/clinically relevant non-major bleeding. Most patients had complete radiological thrombus resolution and no patient had evidence of chronic thromboembolic pulmonary hypertension. There is an urgent need for larger prospective cohort studies/randomized controlled trials to investigate the role of CDT in pediatric PE.

Refractory Thrombocytopenia Is a Valid Early Diagnostic Criteria for Hepatic Veno-Occlusive Disease in Children

We compared the incidence of refractory thrombocytopenia (RT) and platelet transfusion requirements (PTR) in 35 children who developed veno-occlusive disease (VOD) with 35 matched control subjects who underwent hematopoietic stem cell transplant but did not develop VOD. RT developed in 100% of the VOD patients, at a median of 8 days before VOD diagnosis, as compared with 71.5% of the control group. VOD patients required more platelet transfusions than control subjects (median PTR, 6.9 mL/kg [range, .57 to 17.59] versus 3.57 mL/kg [range, 0 to 14.63], respectively) with a statistically significant difference (P < .0001). The number of days with platelet requirements was significantly higher for VOD patients as compared with control subjects (median 68% versus 39%, P =< .0001). The PTR peaked at ~12 mL/kg/day, 2 days before VOD diagnosis, whereas the PTR in the control population was 5 mL/kg/day. The positive predictive value of developing VOD was 88.9% (95% confidence interval, 66.5% to 97%) in patients who were given >7 mL/kg/day of platelets during the at-risk period of days +3 to +13 after transplant. For patients who received >8 mL/kg/day of platelets, the positive predictive value of developing VOD was 86.7% (95% confidence interval, 61.2% to 96.4%). There was no difference in the PTR in patients with mild to moderate VOD as compared with severe VOD; however, the PTR was higher in patients whose VOD did not resolve. The median daily PTR after the diagnosis of VOD in 17 patients who got defibrotide as compared with those who did not get defibrotide was 6.04 mL/kg and 5.72 mL/kg, respectively, but the difference was not statistically significant (P = .56). On univariate and multivariate analysis use of intravenous immunoglobulin was significantly associated with VOD (P = .0088) but was not significantly associated with fatal VOD. In conclusion, RT occurs in 100% of patients at a median of 8 days before VOD diagnosis. VOD should be suspected in any patient with RT after the exclusion of other causes of consumptive thrombocytopenia, especially if they require >7 mL/kg/day of platelets.

PDCT-03. CHEMOTHERAPY STRATEGIES FOR YOUNG CHILDREN NEWLY DIAGNOSED WITH MEDULLOBLASTOMA UP TO THE ERA OF MOLECULAR PROFILING – A COMPARATIVE OUTCOMES ANALYSIS

BACKGROUND/OBJECTIVE

Survival had been poor in several multi-center/national studies since the 1980s attempting to delay, avoid or minimize brain irradiation in young children with medulloblastoma. The introduction of regimens in Germany incorporating both intravenous high-dose (HD-MTX) and intraventricular (IVENT-MTX) methotrexate, as well as regimens in North America incorporating marrow-ablative chemotherapy with autologous hematopoietic cell rescue (HDCx+AuHCR), have reported encouraging outcomes. The objective of this report is to perform a comparative outcomes analysis of these differing strategies.

METHODS

Data from 17 prospective multi-center trials published between 1990 and 2018 for children under six years old with medulloblastoma were reviewed; event-free (EFS) and overall survivals (OS) were compared.

RESULTS

Two trials using full-dose cranio-spinal irradiation with or without chemotherapy reported 5-year survivals of 32–38%. Three trials using standard chemotherapy with delayed irradiation reported 2-4-year EFS and OS of 23–34% and 31–46%. Two trials employing standard chemotherapy without irradiation reported 3-5-year EFS and OS of 22–33% and 34–43%. Four trials incorporating HD-MTX with or without IVENT-MTX reported 5-10-year EFS and OS of 56–59% and 67–80%, and 31% and 59% respectively; one trial with HD-MTX without IVENT-MTX for localized desmoplastic/nodular medulloblastoma (DN-MB) reported 2-year EFS and OS of 52% and 92%. Finally, five trials employing induction chemotherapy, with or without HD-MTX, followed by single or tandem HDCx+AuHCR have reported 3-5-year EFS and OS of 45–60% and 60–70%.

CONCLUSIONS

The best survivals are observed in trials including HD-MTX and IVENT-MTX or including HD-MTX during induction followed by HDCx+AuHCR. Because histology/biology (classic and large cell/anaplastic versus DN-MB; SHH versus non-SHH subtypes) have crucial prognostic roles, EFS and irradiation-free survival advantages require analysis in these settings. The benefit of these trials appears true for all young children with medulloblastoma. Risk-adapted treatment stratification for young children may be improved by molecular profiling of SHH- and non-SHH medulloblastoma.

1753. Adherence and Immunogenicity of Early Vaccination in Pediatric Allogeneic Hematopoietic Cell Transplantation (allo-HCT) Recipients

Background

Allo-HCT recipients are at increased risk for vaccine-preventable infections. Early vaccination (EV) beginning at 3–6 months (mo) post-HCT has been shown to be safe, immunogenic, and is recommended. We assessed adherence and immunogenicity to EV in children post-allo-HCT.

Methods

Retrospective analysis of allo-HCT performed 1/1/10–6/30/18 at NCH. Children who died, relapsed, or received anti-CD20 biologics in the 6 mo preceding intended vaccination were excluded. Institutional guidelines recommend EV starting at 6 (+1) mo post-HCT with: 3 PCV13 + 1 PPSV23, IPV, HBV, DTaP and HIB. Vaccination rates were analyzed at 6(+1), 8(+1) and 10(+1) mo post-HCT and serologies were obtained pre- and ≥ 4 weeks post vaccination. Immunogenicity was defined as antibody (Ab) concentrations ≥ 1.3 µg/mL or a 4 fold rise ≥ 70% of 10 PCV13 serotypes, tetanus (T) and diphtheria (D) Ab ≥ 0.1 IU/mL, and HBs Ab ≥ 10 IU/mL. Non-parametric statistics were applied; correlations between T&B cell subsets and IgG pre-vaccination and specific Ab post-vaccination were performed.

Results

During the 8-year study period, 171 allo-HCT were performed: 131 children were eligible for EV (Table 1); however, EV occurred in only 49.6% (65/131) and was completed in 37.5% (45/120) of children at 10(+1) mo post-HCT. Vaccine immunogenicity of PCV13, HBV, T and D was achieved in 40/45, 34/36, 63/64, and 18/18 of evaluable children, respectively. Protective Ab response after EV for PCV13, HBV, T and D was found in 21/24 (87.5%), 14/16 (87.5%), 35/36 (97.2%), and 8/8 (100%) children, respectively. Specific IgG geometric mean concentration pre- and post-vaccination was similar in children whether they received early or delayed vaccination (median 9.8 mo post-HCT, IQR 8–14) (Figures 1 and 2). No correlations were found between absolute CD4, CD8, CD19 and IgG pre-vaccination and vaccines specific Abs post-vaccination (Figure 3).

Conclusion

Despite recommendations, adherence to EV was low among our cohort of allo-HCT recipients and identified opportunities for improvement. Overall, vaccines were immunogenic with no significant differences in Ab concentrations among patients receiving early vs. delayed vaccination. No robust correlations were found between number of T&B cells or total IgG and Ab titers.

Disclosures

All authors: No reported disclosures.

A Multidimensional Electronic Hydroxyurea Adherence Intervention for Children With Sickle Cell Disease: Single-Arm Before-After Study

Background

Hydroxyurea is a disease-modifying medication for patients with sickle cell disease (SCD). Despite demonstrated efficacy, hydroxyurea nonadherence in clinical practice is common and results in worse health outcomes for nonadherent patients. Mobile Directly Observed Therapy (Mobile DOT) is a pilot-tested, electronic, multidimensional hydroxyurea adherence intervention for children with SCD. Mobile DOT includes sending daily text message reminders to patients to take hydroxyurea, patients recording and sending daily videos that capture their hydroxyurea administrations for the research team to review and track adherence, providing personalized feedback to patients about their adherence, and providing small monetary incentives to patients if they achieve high hydroxyurea adherence.

Objective

This study aimed to determine if Mobile DOT increases hydroxyurea adherence in children with SCD and to explore its impact on hematologic and clinical outcomes.

Methods

This was a single-arm, 6-month intervention study of patients with SCD on hydroxyurea who were aged ≤19 years and reported having access to an electronic device. Participants’ hydroxyurea adherence when they received Mobile DOT was compared with their adherence 6 months before and after receiving Mobile DOT. Participants’ medication possession ratio (MPR) was calculated from their pharmacy dispensing records and was used to measure adherence. Laboratory and clinical outcomes were abstracted from participants’ electronic medical records. Infrequently hospitalized patients who received at least 160 days of the intervention were considered to be engaged participants.

Results

Of 91 patients who were approached, 55 enrolled and 34 engaged with Mobile DOT. The median age of the engaged participants was 10 years (range 2-18.8 years), and 21 (62%, 21/34) participants were male, 28 (82%, 21/34) had hemoglobin SS SCD, and 19 (56%, 19/34) were prescribed hydroxyurea for at least a year before enrollment. With Mobile DOT, engaged participants’ median MPR increased from 61.7% to 84.4% (P<.001) and significantly more (67% vs 30%; P=.002) achieved ≥80% hydroxyurea adherence compared with baseline values. Engaged participants’ mean fetal hemoglobin (HgbF) levels and mean corpuscular volumes (MCV) improved significantly after 6 months of Mobile DOT (P=.04 and P=.001, respectively), but their adherence, HgbF levels, and MCV returned to baseline values during the 6 months after the intervention. Hospitalizations and the clinical outcomes that were measured occurred infrequently during the study. Nonengagement was associated with being female and having a recent SCD complication. In addition, having insufficient electronic data, being unable to quickly complete Mobile DOT each day, and not perceiving that Mobile DOT was beneficial may have further decreased engagement.

Conclusions

Mobile DOT shows promise as an effective intervention for some children with SCD. Modifications that may improve recruitment, reduce attrition, and increase engagement were identified and could increase the impact that Mobile DOT has on children with SCD.

Trial Registration

ClinicalTrials.gov NCT02578017; https://clinicaltrials.gov/ct2/show/NCT02578017

Presacral masses and sacrococcygeal teratomas in patients with and without anorectal malformations: A single institution comparative study

BACKGROUND

Despite variability at presentation, presacral masses in patients with and without anorectal malformations (ARM) appear histologically similar. The purpose of this study was to identify differences in oncologic outcomes between these two groups.

METHODS

A retrospective review was performed utilizing our institutional cancer and colorectal and pelvic reconstruction databases for patients with presacral masses and sacrococcygeal teratomas between 1990 and 2017. Data captured included age at surgical resection, type of ARM, tumor location within the pelvis, tumor histopathology, tumor size, adjuvant chemotherapy, recurrence, and follow-up.

RESULTS

Forty-six patients comprised our cohort, of whom 12 had an ARM. The median age was older at resection for those with an ARM (1.4 years; range 1 day to 29.4 years) compared to those without an ARM (9 days; range 0 days to 6.9 years) (p = 0.01). The mean tumor size was 2.5 cm in patients with an ARM compared to 6.0 cm in patients without an ARM (p = 0.036). All patients with ARM had exclusively intrapelvic tumors, and histopathology included mature teratoma (8), yolk sac tumor (1), lipoma (1), and unknown (2). Tumor location for patients with sacral and presacral masses without ARM included exclusively extrapelvic (10), primarily extrapelvic with large intrapelvic component (7), primarily intrapelvic with extrapelvic component (1), exclusively intrapelvic (8), and unknown (8). Histopathology for patients with presacral masses without ARM included mature teratoma (20), immature teratoma (7), yolk sac tumor (3), ganglioneuroma (1), neuroblastoma (1), benign epithelial cyst (1), and unknown (1). Tumor recurrence rate was similar between patients with ARM (n = 3, 25%) and those without an ARM (n = 5, 15%) (p = 0.41). The 5-year event free survival was 65% (95% CI: 25%-87%) in the group with ARM and 81% (95% CI: 60%-92%) in the group without ARM (p = 0.44).

CONCLUSION

Sacral and presacral masses in patients with ARM are resected at a later age and are more likely to be intrapelvic. They appear histologically similar and have similar rates of recurrence and malignancy when compared to patients without ARM.

LEVEL OF EVIDENCE

III TYPE OF STUDY: Retrospective comparative study.

Treatment-Related Outcomes in Paget-Schroetter Syndrome-A Cross-Sectional Investigation

OBJECTIVE

To investigate treatment-related outcomes, namely radiological clot resolution, post-thrombotic syndrome (PTS), and health related quality-of-life (HRQoL) scores, in children with Paget-Schroetter syndrome (PSS) undergoing multidisciplinary management, including anticoagulation and decompressive rib-resection surgery, with or without thrombolytic therapy.

STUDY DESIGN

We identified all patients treated for PSS at our institution between the years 2010 and 2017. Baseline clinical and radiologic data were abstracted from medical records. Two validated survey instruments to quantify PTS and HRQoL were mailed to eligible patients. Standard statistical methods were used to summarize these measures.

RESULTS

In total, 22 eligible patients were identified; 10 were treated with thrombolysis followed by anticoagulation and rib resection, and 12 were treated with anticoagulation and rib resection alone. Nineteen patients responded to the survey instruments. Median age at deep vein thrombosis diagnosis and survey completion were 16.3 and 20.4 years, respectively. Nineteen of 22 patients had thrombus resolution on radiologic follow-up. Fourteen of 19 survey respondents reported signs/symptoms of PTS of which the majority (12/14) reported mild PTS. Aggregate total, physical, and psychosocial HRQoL scores reported were 90.6, 96.7, and 93.3, respectively. Thrombolytic therapy was not associated with a significant improvement in radiologic, clinical or HRQoL outcomes.

CONCLUSIONS

Most patients with PSS had complete thrombus resolution on imaging. Only 11% of survey respondents reported moderate PTS. The entire cohort reported excellent HRQoL scores. The role for thrombolytic therapy in the management of childhood PSS remains incompletely elucidated.

Impact of erythrocytapheresis on natural anticoagulant levels in children with sickle cell disease: A pilot study

Venous thromboembolism (VTE) is being increasingly recognized in children with sickle cell disease (SCD). In a retrospective cohort study, we identified bilateral central venous catheter (CVC) placement as an independent risk factor for VTE. At our institution, the only indication for bilateral CVC placement in children with SCD is erythrocytapheresis. To investigate the impact of erythrocytapheresis on coagulation, we measured levels of natural anticoagulants in 11 patients with SCD on chronic erythrocytapheresis, immediately before and after apheresis. We demonstrated a statistically significant reduction in most parameters. Additional studies are needed to further investigate the exact etiology and clinical impact of this acute decrease.