D-dimer and sinusoidal obstructive syndrome-novel poor prognostic features of thrombotic microangiopathy in children after hematopoietic cellular therapy in a single institution prospective cohort study.

Transplant-associated thrombotic microangiopathy (TA-TMA) is a common, severe complication of allogeneic hematopoietic cellular therapy (HCT). Even when treated in many studies, morbidity and mortality rates are high. This prospective single-institution cohort study serially enrolled all allogeneic HCT recipients from August 2019-August 2022. Patients were universally screened for TA-TMA and intermediate and high-risk patients were immediately treated with eculizumab. Sub-distribution cox-proportional hazards models were used to identify sub-distribution hazard ratios (sHR)  for multi-organ dysfunction (MOD) and non-relapse-related mortality (NRM). Of 136 patients, 36 (26%) were diagnosed with TA-TMA and 21/36 (58%) developed MOD, significantly more than those without TA-TMA, (p < .0001). Of those with TA-TMA, 18 (50%) had high-risk TA-TMA (HR-TA-TMA), 11 (31%) had intermediate-risk TA-TMA (IR-TA-TMA), and 8 (22%) had standard risk (SR-TA-TMA). Twenty-six were treated with eculizumab (1/8 SR, 7/11 IR, and 18/18 HR). Elevated D-dimer predicted the development of MOD (sHR 7.6, 95% confidence interval [CI] 1.8-32.3). Children with concurrent sinusoidal obstructive syndrome (SOS) and TA-TMA had an excess risk of MOD of 34% and data supported a biologic interaction. The adjusted NRM risk was significantly higher in the TA-TMA patients (sHR 10.54, 95% CI 3.8-29.2, p < .0001), despite prompt treatment with eculizumab. Significant RF for NRM in TA-TMA patients included SOS (HR 2.89, 95% 1.07-7.80) and elevated D-dimer (HR 3.82, 95% CI 1.14-12.84). An unrelated donor source and random urine protein to creatine ratio ≥2 mg/mg were significantly associated with no response to eculizumab (odds ratio 15, 95% CI 2.0-113.6 and OR 6.5, 95% CI 1.1-38.6 respectively). TA-TMA was independently associated with NRM despite early diagnosis and treatment with eculizumab in this large pediatric transplant cohort. Prognostic implications of D-dimer in TA-TMA merit further investigation as this is a readily accessible biomarker. Concurrent SOS is an exclusion criterion of many ongoing clinical trials, but these data highlight these patients could benefit from novel therapeutic approaches. Multi-institutional clinical trials are needed to understand the impact of TA-TMA-targeted therapies.

Mismatched Unrelated Donor Hematopoietic Stem Cell Transplantation Rescues Marrow Failure From Acute Leukemia Therapy in a Patient With Previously Undiagnosed Ligase IV Syndrome.

Patients with DNA double-strand breakage repair disorders are at increased risk of malignancy which is often difficult to treat given underlying sensitivity to chemotherapy and radiotherapy, lending an important role to hematopoietic stem cell transplantation. The choice of conditioning regimen used must balance reducing risk of rejection with minimizing excessive toxicity from myeloablative chemotherapy or ionizing radiation. We describe successful engraftment following a nonmyeloablative hematopoietic stem cell transplantation in a patient with Ligase IV syndrome and numerous pretransplant complications including malignancy, cardiac failure, and secondary hemophagocytic lymphohistiocytosis. Congruent with prior reports, a reduced intensity regimen appears efficacious in Ligase IV syndrome patients.

Real World Application of Recently Proposed ASTCT/CIBMTR/ eBMT/ APBMT Consensus Risk Stratification for Transplant Associated Thrombotic Microangiopathy (TA-TMA) in Children.

BACKGROUND: Consensus diagnostic and risk stratification of transplant associated thrombotic microangiopathy (TA-TMA) was recently achieved from international transplantation groups (Schoettler et al, TCT, 2023). While the diagnostic criteria proposed have been applied to multiple pediatric cohorts, there are scant data applying the novel risk stratification approach in children with TA-TMA. METHODS: In this retrospective cohort study, all children undergoing an allogeneic HCT or autologous HCT for neuroblastoma were prospectively screened for TA-TMA, diagnosed and risk-stratified using Jodele criteria from August 2019- October 2023. Our institutional practice during the study period was treat all Jodele intermediate and high-risk patients (IR, HR) with eculizumab. Harmonization risk stratification criteria were retrospectively applied. All survival analyses were calculated from the day of TA-TMA diagnosis. To identify which specific harmonization high-risk feature(s) were the most important predictors for NRM, full and reduced logistic regression models were tested. The lowest BIC and optimal Mallows' CP statistic were used to identify the best subset. SAS 9.4 (Cary, NC) was used to complete the analysis. RESULTS: Fifty-two children were diagnosed with TA-TMA during the study period a median of 37.5 days post HCT (range 3 to 735). Using Jodele risk stratification, 11 (21%) were SR, 21 (40%) intermediate risk, and 20 (39%) high- risk (HR). Forty (77%) were treated with eculizumab. There were no statistically significant differences in NRM among Jodele risk groups, though overall survival was significantly different. Using the harmonized stratification, 49 (94%) of children were stratified as HR and 3 as SR, there were no statistically significant differences in NRM or OS between groups. Eight (15.4%) children were classified as SR using Jodele risk stratification but re-stratified as HR using the harmonization criteria. One (12.5%) died in the setting of severe GVHD and the remaining 7 patients are alive at last follow up. In a best subset model, LDH >2x ULN (OR 6.52, 95% CI 0.96-44.3, p=0.05), grade 2-4 acute GVHD at the time of TA-TMA diagnosis (OR 15.4, 95% CI 2.14- 110.68, p=0.01), and multi-organ dysfunction at the time of TA-TMA (OR 21.5, 95% CI 2.96-156.37, p=0.002) were significantly associated with NRM; elevated sC5b-9, rUPCR, and viral infections were not significantly associated with NRM. Using these best fit criteria, 14 patients were classified as SR and 38 as HR; NRM was significantly higher and OS significantly lower. DISCUSSION: In this cohort of children with TA-TMA retrospective application of harmonization criteria resulted in more patients stratified as HR than previously described Jodele criteria. The intention of the harmonization criteria was to identify those at highest risk of poor outcomes; while all harmonization SR patients survived, this risk stratification was very sensitive. Previous criticisms of harmonization risk stratification include limited access to sC5b-9 testing- these data suggest that concurrent MOD, acute GVHD, and LDH >2X ULN are the most important predicators of NRM in this cohort, supporting the use of harmonization risk stratification even in the absence of available sC5b-9 testing. Additional studies are needed to validate these findings.

Compassionate Use Narsoplimab for Severe Refractory Transplantation-Associated Thrombotic Microangiopathy in Children.

Transplant-associated thrombotic microangiopathy (TA-TMA) is a common and potentially severe complication of hematopoietic cell transplantation. TA-TMA-directed therapy with eculizumab, a complement C5 inhibitor, has resulted in a survival benefit in some studies. However, children with TA-TMA refractory to C5 inhibition with eculizumab (rTA-TMA) have mortality rates exceeding 80%, and there are no other known therapies. Narsoplimab, an inhibitor of the MASP-2 effector enzyme of the lectin pathway, has been studied in adults with TA-TMA as first-line therapy with a response rate of 61%. Although there are limited data on narsoplimab use as a second-line agent in children, we hypothesized, that complement pathways proximal to C5 are activated in rTA-TMA, and that narsoplimab may ameliorate rTA-TMA in children. In this single-center study, children were enrolled on single-patient, Institutional Review Board-approved compassionate use protocols for narsoplimab treatment. Clinical complement lab tests were obtained at the discretion of the treating physician, although all patients were also offered participation in a companion biomarker study. Research blood samples were obtained at the time of TA-TMA diagnosis, prior to eculizumab treatment, at the time of refractory TA-TMA diagnosis prior to the first narsoplimab dose, and 2 weeks after the first narsoplimab dose. Single ELISA kits were used to measure markers of complement activation according to the manufacture's instructions. Five children with rTA-TMA received narsoplimab; 3 were in multiorgan failure and 2 had worsening multiorgan dysfunction at the time of treatment. Additional comorbidities at the time of treatment included sinusoidal obstructive syndrome (SOS; n = 3), viral infection (n = 3), and steroid-refractory stage 4 lower gut grade IV acute graft-versus-host disease (aGVHD, n = 3). Two infants with concurrent SOS and no aGVHD had resolution of organ dysfunction; 1 also developed transfusion-independence (complete response), and the other's hematologic response was not assessable in the setting of leukemia and chemotherapy (partial response). One additional patient achieved transfusion independence but had no improvement in organ manifestations (partial response), and 2 patients treated late in the course of disease had no response. Narsoplimab was well tolerated without any attributed adverse effects. Three patients consented to provide additional research blood samples. One patient with resolution of organ failure demonstrated evidence of proximal pathway activation prior to narsoplimab treatment with subsequent declines in Ba, Bb, C3a, and C5a and increases in C3 in both clinical and research lab tests. Otherwise, there was no clear pattern of other complement markers, including MASP-2 levels, after therapy. In this cohort of ill children with rTA-TMA and multiple comorbidities, 3 patients benefited from narsoplimab. Notably, the 2 patients with resolution of organ involvement did not have steroid-refractory aGVHD, which is thought to be a critical driver of TA-TMA. Additional studies are needed to determine which patients are most likely to benefit from narsoplimab and which markers may be most helpful for monitoring lectin pathway activation and inhibition.

Fertility Preservation Practices at Pediatric Oncology Institutions in the United States: A Report From the Children's Oncology Group.

PURPOSE: Fertility discussions are an integral part of comprehensive care for pediatric, adolescent, and young adult patients newly diagnosed with cancer and are supported by national guidelines. Current institutional practices are poorly understood. METHODS: A cross-sectional survey was distributed to 220 Children's Oncology Group member institutions regarding fertility discussion practices. Descriptive statistics were calculated for all variables. The association between specific practices and selected outcomes on the basis of sex was examined via multivariable logistic regression. RESULTS: One hundred forty-four programs (65.5%) returned surveys. Of these, 65 (45.1%) reported routine discussions of fertility with all female patients and 55 (38.5%) all male patients (P = .25). Ninety-two (63.8%) reported no specific criteria for offering females fertility preservation (FP), compared with 40 (27.7%) for males (P < .001). Program characteristics associated with fertility discussions included reproductive endocrinology and infertility on site (females odds ratio [OR], 2.1; 95% CI, 1.0 to 4.3), discussion documentation mandate (females OR, 2.3; 95% CI, 1.0 to 5.5; males OR, 3.5; 95% CI, 1.4 to 8.7), and cumulative institution-based FP infrastructure (which included [1] routine practice of documentation, [2] template for documentation, [3] mandate for documentation, and [4] availability of FP navigation; females OR, 1.6; 95% CI, 1.1 to 2.3; males OR, 2.3; 95% CI, 1.6 to 3.4). Utilization of practices unsupported by guidelines included offering sperm banking after treatment initiation (39/135 programs; 28.9%), gonadotropin-releasing hormone analogs for ovarian suppression/FP (75/144 programs; 52.1%), ovarian tissue cryopreservation at diagnosis for patients with leukemia (19/64 programs; 29.7%), and testicular tissue cryopreservation (23/138 programs; 16.7%) not part of a clinical trial. CONCLUSION: Despite recommended guidelines, fertility discussions with patients/families before treatment initiation are not routine at Children's Oncology Group institutions. Standard criteria to determine which options should be offered to patients are more common for males than females.

BCMA CAR-T induces complete and durable remission in refractory plasmablastic lymphoma.

Plasmablastic lymphoma (PBL) is a rare subtype of aggressive large B-cell lymphoma, with a dismal prognosis despite aggressive therapies. New approaches are needed for those with refractory disease. PBL expresses antigens similar to multiple myeloma (MM), including B-cell maturation antigen (BCMA). Chimeric antigen receptor T-cell (CAR-T) therapy directed against BCMA has shown efficacy for the treatment of heavily pretreated MM with low rates of grades 3 and 4 cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) in a phase Ib/II trial (A Study of JNJ-68284528, a CAR-T Directed Against BCMA in Participants With Relapsed or Refractory Multiple Myeloma (CARTITUDE-1), NCT03548207). However, data for the use of BCMA CAR-T for treating PBL are lacking.We report a challenging case of multiple refractory PBL that emerged from B-cell acute lymphoblastic leukemia in an adolescent who failed to respond to an allogeneic hematopoietic cell transplant. The patient developed rapidly advancing disease despite withdrawal of immunosuppression, treatment with etoposide, ibrutinib, and daratumumab, prompting consideration of BCMA CAR-T (under emergency investigational new drug (eIND)). The patient achieved a complete remission (CR), without recurrent acute graft versus host disease (GVHD), CRS or ICANS after BCMA CAR-T therapy. BCMA CAR-T expansion was detected in vivo, peaking on day 15. The patient remains in CR for more than a year post CAR-T therapy, supporting consideration of immunotherapy for future patients with refractory PBL, a disease with few treatment options.

Nutritional Support: Enteral Nutrition Pathway for Children Undergoing Hematopoietic Stem Cell Transplantation.

BACKGROUND:  Children undergoing a hematopoietic stem cell transplantation (HSCT) are at a higher risk for malnutrition, which could be reduced by enteral nutrition (EN) support. OBJECTIVES:  This study evaluated the safety and feasibility of implementing an EN pathway for children undergoing HSCT. METHODS:  An evidence-based, standardized EN pathway was implemented for children undergoing HSCT. Parenteral nutrition and EN rates were compared among patients pre- and postimplementation, and t tests and chi-square tests were performed. FINDINGS:  A larger proportion of patients received EN and had an increased number of EN days (8.3 versus 5.3 days) postimplementation, which was clinically significant but not statistically significant. Postimplementation, 15 patients required EN and parenteral nutrition. The EN pathway was safe, but had limited feasibility because of the difficulty of placing and maintaining the nasojejunal tube.

Comparison of Anti-Mullerian Hormone Levels Pre- and Post-Hematopoietic Cell Transplantation in Pediatric and Adolescent Females with Sickle Cell Disease.

Allogeneic hematopoietic cell therapy (HCT) is an established cure for sickle cell disease (SCD); however, HCT conditioning regimens are known to be gonadotoxic. Anti-mullerian hormone (AMH) measures ovarian reserve, and follicle-stimulating hormone (FSH) defines premature ovarian insufficiency (POI) at values >40 mIU/mL in pubertal females. The present study was conducted to assess ovarian reserve and function before and after transplantation in pediatric and adolescent females with SCD treated with allogeneic HCT between January 2015 and June 2020 at Children's Healthcare of Atlanta. In this retrospective review of 17 females age <21 years with SCD who had AMH levels measured at baseline and at 2 years post-HCT, AMH levels were categorized as normal, low, or undetectable, and FSH levels were measured and used to identify pubertal females who had developed POI. Demographic and treatment data were abstracted from the institutional database and medical records, and a descriptive statistical analysis was conducted. Of the 17 patients in the study cohort, 14 had been treated with hydroxyurea and 3 had chronic transfusions but with no significant iron overload. AMH levels were normal in 15 patients (88%) and low in 2 patients (12%) at baseline. The median age at HCT was 7.5 years (range, 3.7 to 20.3 years), and 14 patients (82%) underwent matched related donor HCT. After HCT, 15 patients (88%) had undetectable AMH and 2 (12%) had low AMH, with no apparent differences by HCT conditioning regimen. No pubertal patients had POI at baseline, whereas 55% of pubertal patients had progressed to POI by 2 years post-HCT. In this cohort, the majority of females had normal AMH levels at baseline but undetectable levels after HCT. Females with SCD considering HCT should be counseled about the treatment-related risk of gonadal dysfunction. © 2022 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Infrastructure of Fertility Preservation Services for Pediatric Cancer Patients: A Report From the Children's Oncology Group.

PURPOSE: Fertility preservation (FP) services are part of comprehensive care for those newly diagnosed with cancer. The capacity to offer these services to children and adolescents with cancer is unknown. METHODS: A cross-sectional survey was sent to 220 Children's Oncology Group member institutions regarding institutional characteristics, structure and organization of FP services, and barriers to FP. Standard descriptive statistics were computed for all variables. The association between site-specific factors and selected outcomes was examined using multivariable logistic regression. RESULTS: One hundred forty-four programs (65.5%) returned surveys. Fifty-three (36.8%) reported a designated FP individual or team. Sperm banking was offered at 135 (97.8%) institutions, and testicular tissue cryopreservation at 37 (27.0%). Oocyte and embryo cryopreservation were offered at 91 (67.9%) and 62 (46.6%) institutions, respectively; ovarian tissue cryopreservation was offered at 64 (47.8%) institutions. The presence of dedicated FP personnel was independently associated with the ability to offer oocyte or embryo cryopreservation (odds ratio [OR], 4.7; 95% CI, 1.7 to 13.5), ovarian tissue cryopreservation (OR, 2.7; 95% CI, 1.2 to 6.0), and testicular tissue cryopreservation (OR, 3.3; 95% CI, 1.4 to 97.8). Only 26 (18.1%) participating institutions offered all current nonexperimental FP interventions. Barriers included cost (70.9%), inadequate knowledge or training (60.7%), difficulty characterizing fertility risk (50.4%), inadequate staffing (45.5%), and logistics with reproductive specialties (38%-39%). CONCLUSION: This study provides the most comprehensive view of the current landscape of FP infrastructure for children and adolescents with cancer and demonstrates that existing infrastructure is inadequate to offer comprehensive services to patients. We discuss modifiable factors to improve patient access to FP.