Long-Term Outcomes in Patients With Localized Ewing Sarcoma Treated With Interval-Compressed Chemotherapy on Children's Oncology Group Study AEWS0031

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Long-term outcomes from Children's Oncology Group study AEWS0031 were assessed to determine whether the survival advantage of interval-compressed chemotherapy (ICC) was maintained over 10 years in patients with localized Ewing sarcoma (ES). AEWS0031 enrolled 568 eligible patients. Patients were randomly assigned to receive vincristine-doxorubicin-cyclophosphamide and ifosfamide-etoposide alternating once every 3 weeks (standard timing chemotherapy [STC]) versus once every 2 weeks (ICC). For this updated report, one patient was excluded because of uncertainty of original diagnosis. The 10-year event-free survival (EFS) was 70% with ICC compared with 61% with STC (P = .03), and 10-year overall survival (OS) was 76% with ICC compared with 69% with STC (P = .04). There was no difference in the 10-year cumulative incidence of second malignant neoplasms (SMNs; PC [see Data Supplement, online only] = .5). A test for interaction demonstrated that ICC provided greater risk reduction for patients with tumor volume ≥200 mL than for patients with tumors <200 mL, but no evidence for a significant interaction in other subgroups defined by age, primary site, and histologic response. With longer-term follow-up, ICC for localized ES is associated with superior EFS and OS without an increased risk for SMN compared with STC. ICC is associated with improved outcomes even in adverse-risk patient groups.

Children's Oncology Group's 2023 blueprint for research: Young investigators

The Children's Oncology Group (COG) Young Investigators (YI) Committee is an administrative committee in which liaisons represent 30 COG committees, and was created to facilitate the integration of YIs into the organization, and prepare them for future COG leadership roles. The mentorship program has mentored over 400 YIs since 2005 and currently has 175 active participants. The COG YI Master Roster is a database YIs can join, which allows them to post their interests and accomplishments to COG leadership, and 321 YIs have already joined this list. The YI Committee has held virtual symposia designed to describe how COG operates and provide guidance on how YIs can reach their goals; over 300 YIs have attended these since 2021 and have consistently rated them as helpful. Through these and other elements of the program, the YI Committee remains committed to developing a future pipeline of new investigators.

A phase 1 study of simvastatin in combination with topotecan and cyclophosphamide in pediatric patients with relapsed and/or refractory solid and CNS tumors

BACKGROUND

3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) can inhibit tumor proliferation, angiogenesis, and restore apoptosis in preclinical pediatric solid tumor models. We conducted a phase 1 trial to determine the maximum tolerated dose (MTD) of simvastatin with topotecan and cyclophosphamide in children with relapsed/refractory solid and central nervous system (CNS) tumors.

METHODS

Simvastatin was administered orally twice daily on days 1-21, with topotecan and cyclophosphamide intravenously on days 1-5 of a 21-day cycle. Four simvastatin dose levels (DLs) were planned, 140 (DL1), 180 (DL2), 225 (DL3), 290 (DL4) mg/m² /dose, with a de-escalation DL of 100 mg/m² /dose (DL0) if needed. Pharmacokinetic and pharmacodynamic analyses were performed during cycle 1.

RESULTS

The median age of 14 eligible patients was 11.5 years (range: 1-23). The most common diagnoses were neuroblastoma (N = 4) and Ewing sarcoma (N = 3). Eleven dose-limiting toxicity (DLT)-evaluable patients received a median of four cycles (range: 1-6). There were three cycle 1 DLTs: one each grade 3 diarrhea and grade 4 creatine phosphokinase (CPK) elevations at DL1, and one grade 4 CPK elevation at DL0. All patients experienced at least one grade 3/4 hematologic toxicity. Best overall response was partial response in one patient with Ewing sarcoma (DL0) and stable disease for four or more cycles in four patients. Simvastatin exposure increased with higher doses and may have correlated with toxicity. Plasma interleukin 6 (IL-6) concentrations (N = 6) showed sustained IL-6 reductions with decrease to normal values by day 21 in all patients, indicating potential on-target effects.

CONCLUSIONS

The MTD of simvastatin with topotecan and cyclophosphamide was determined to be 100 mg/m² /dose.

Progression-Free Survival and Patterns of Response in Patients With Relapsed High-Risk Neuroblastoma Treated With Irinotecan/Temozolomide/Dinutuximab/Granulocyte-Macrophage Colony-Stimulating Factor

PURPOSE

Although chemoimmunotherapy is widely used for treatment of children with relapsed high-risk neuroblastoma (HRNB), little is known about timing, duration, and evolution of response after irinotecan/temozolomide/dinutuximab/granulocyte-macrophage colony-stimulating factor (I/T/DIN/GM-CSF) therapy.

PATIENTS AND METHODS

Patients eligible for this retrospective study were age < 30 years at diagnosis of HRNB and received ≥ 1 cycle of I/T/DIN/GM-CSF for relapsed or progressive disease. Patients with primary refractory disease who progressed through induction were excluded. Responses were evaluated using the International Neuroblastoma Response Criteria.

RESULTS

One hundred forty-six patients were included. Tumors were MYCN-amplified in 50 of 134 (37%). Seventy-one patients (49%) had an objective response to I/T/DIN/GM-CSF (objective response; 29% complete response, 14% partial response [PR], 5% minor response [MR], 21% stable disease [SD], and 30% progressive disease). Of patients with SD or better at first post-I/T/DIN/GM-CSF disease evaluation, 22% had an improved response per International Neuroblastoma Response Criteria on subsequent evaluation (13% of patients with initial SD, 33% with MR, and 41% with PR). Patients received a median of 4.5 (range, 1-31) cycles. The median progression-free survival (PFS) was 13.1 months, and the 1-year PFS and 2-year PFS were 50% and 28%, respectively. The median duration of response was 15.9 months; the median PFS off all anticancer therapy was 10.4 months after discontinuation of I/T/DIN/GM-CSF.

CONCLUSION

Approximately half of patients receiving I/T/DIN/GM-CSF for relapsed HRNB had objective responses. Patients with initial SD were unlikely to have an objective response, but > 1 of 3 patients with MR/PR on first evaluation ultimately had complete response. I/T/DIN/GM-CSF was associated with extended PFS in responders both during and after discontinuation of treatment. This study establishes a new comparator for response and survival in patients with relapsed HRNB.

Infectious events in pediatric patients with acute lymphoblastic leukemia/lymphoma undergoing evaluation for fever without severe neutropenia

BACKGROUND

Infections cause significant treatment-related morbidity during pediatric acute lymphoblastic leukemia/lymphoma (ALL/LLy) therapy. Fevers during periods without severe neutropenia are common, but etiologies are not well-described. This study sought to describe the bloodstream infection (BSI) and non-BSI risk in children undergoing therapy for ALL/LLy.

METHODS

Demographic and clinical data were abstracted for febrile episodes without severe neutropenia at two children's hospitals. Treatment courses were stratified by intensity. Multivariate logistic regression evaluated characteristics associated with infection.

RESULTS

There were 1591 febrile episodes experienced by 524 patients. Of these, 536 (34%) episodes had ≥1 infection; BSI occurred in 30 (1.9%) episodes. No BSIs occurred in episodes with a recent procedural sedation or cytarabine exposure. Presence of hypotension, chills/rigors, higher temperature, and infant phenotype were independently associated with BSI (p < .05). Of the 572 non-BSIs, the most common was upper respiratory infection (URI) (n = 381, 67%). Compared to episodes without infection, URI symptoms, higher temperature, absolute neutrophil count 500-999/μl, and evaluation during a low-intensity treatment course were more likely to be associated with a non-BSI (p < .05) and inpatient status was less likely to be associated with a non-BSI (p < .05).

CONCLUSIONS

The BSI rate in pediatric patients with ALL/LLy and fever without severe neutropenia is low, but one-third of the time, patients have a non-BSI. Future research should test if the need for empiric antibiotics can be tailored based on the associations identified in this study.

Entrectinib in children and young adults with solid or primary CNS tumors harboring NTRK, ROS1, or ALK aberrations (STARTRK-NG)

BACKGROUND

Entrectinib is a TRKA/B/C, ROS1, ALK tyrosine kinase inhibitor approved for the treatment of adults and children aged ≥12 years with NTRK fusion-positive solid tumors and adults with ROS1 fusion-positive non-small-cell lung cancer. We report an analysis of the STARTRK-NG trial, investigating the recommended phase 2 dose (RP2D) and activity of entrectinib in pediatric patients with solid tumors including primary central nervous system tumors.

METHODS

STARTRK-NG (NCT02650401) is a phase 1/2 trial. Phase 1, dose-escalation of oral, once-daily entrectinib, enrolled patients aged <22 years with solid tumors with/without target NTRK1/2/3, ROS1, or ALK fusions. Phase 2, basket trial at the RP2D, enrolled patients with intracranial or extracranial solid tumors harboring target fusions or neuroblastoma. Primary endpoints: phase 1, RP2D based on toxicity; phase 2, objective response rate (ORR) in patients harboring target fusions. Safety-evaluable patients: ≥1 dose of entrectinib; response-evaluable patients: measurable/evaluable baseline disease and ≥1 dose at RP2D.

RESULTS

At data cutoff, 43 patients, median age of 7 years, were response-evaluable. In phase 1, 4 patients experienced dose-limiting toxicities. The most common treatment-related adverse event was weight gain (48.8%). Nine patients experienced bone fractures (20.9%). In patients with fusion-positive tumors, ORR was 57.7% (95% CI 36.9-76.7), median duration of response was not reached, and median (interquartile range) duration of treatment was 10.6 months (4.2-18.4).

CONCLUSIONS

Entrectinib resulted in rapid and durable responses in pediatric patients with solid tumors harboring NTRK1/2/3 or ROS1 fusions.

Progression-free survival and patterns of response in patients with high-risk neuroblastoma (HR-NB) treated with irinotecan/temozolomide/dinutuximab/granulocyte-macrophage colony-stimulating factor (I/T/DIN/GM-CSFS) chemoimmunotherapy

10025

Background: Encouraging responses to chemoimmunotherapy with I/T/DIN/GM-CSF have been observed in trials for patients (pts) with relapsed/refractory HR-NBL, but factors associated with response have not been identified and duration of response has not been assessed. We aimed to evaluate timing and duration of response among pts with relapsed HR-NBL treated with I/T/DIN/GM-CSF and identify factors associated with response. Methods: We performed a multicenter retrospective cohort study of pts treated with I/T/DIN/GM-CSF. Eligibility criteria included: diagnosis of relapsed HR-NBL prior to age 30; objective response [OR; complete, partial, or minor response (CR, PR, or MR) by International Neuroblastoma Response Criteria (INRC)] or stable disease (SD) after initial therapy; receipt of I/T/DIN/GM-CSF for relapse or progression outside a clinical trial from 1/1/15-6/1/20. Logistic regression was used to identify factors associated with OR. Kaplan Meier analysis was used to determine progression-free survival (PFS). Results: We enrolled 143 pts with a median age at diagnosis of 51 months. Tumors were MYCN amplified in 52 (36%) and ALK was wild type in 73/94 (78% of tumors in which ALK status was known). 79 (55%) had received prior anti-GD2 therapy. I/T/DIN/GM-CSF comprised first relapse therapy in 96 pts (67%), second relapse therapy in 23 (16%) and subsequent therapy in 24 (17%). 70 (49%) achieved OR following I/T/DIN/GM-CSF therapy [29% CR, 15% PR, 5% MR], 30 (21%) achieved SD and 43 (30%) progressed. Median cycles received was 5 (range 1-31). 121 patients (85%) had their best response upon first disease evaluation. Later disease evaluations showed improved INRC classification in 14% of pts with initial SD, 33% with MR, and 41% with PR. Median time to OR was 2 months (range 1-21). Of the 105 relapse/progression events after starting I/T/DIN/GM-CSF (73% of pts), 59 (56%) occurred during therapy. Of the 42 pts who achieved CR with I/T/DIN/GM-CSF, 5 (12%) relapsed during I/T/DIN/GM-CSF and 17 (40%) relapsed after discontinuation. I/T/DIN/GM-CSF was discontinued in 83 pts (58%) due to suboptimal response or PD, and in 19 (13%) for toxicity. Median PFS among objective responders was 15.5 months. Among those in CR, median PFS after discontinuation of I/T/DIN/GM-CSF was 11.8 months (range 0.7-70.6). Multivariable models did not identify clinical or biologic factors associated with OR. Conclusions: 49% of pts receiving I/T/DIN/GM-CSF for relapsed HR-NBL achieved OR. Among responders, median response duration was 15.5 months. Pts with SD on first disease evaluation were unlikely to achieve OR, but > 1/3 of pts with MR/PR on first evaluation ultimately achieved CR. No identifiable clinical or biologic factors were associated with OR.

Long-term outcomes in patients with localized Ewing sarcoma treated with interval-compressed chemotherapy: A long-term follow-up report from Children’s Oncology Group study AEWS0031

11505

Background: Children’s Oncology Group study AEWS0031 demonstrated superior 5-year event-free survival (EFS) in patients with localized Ewing sarcoma (ES) receiving interval-compressed (IC) chemotherapy (every 2 weeks) compared to standard timing (ST) chemotherapy (every 3 weeks). We assessed the long-term outcome of patients treated on AEWS0031 to determine whether the survival advantage of IC chemotherapy was maintained at 10 years. Methods: AEWS0031 enrolled 568 eligible patients with localized ES. Patients were stratified into four groups by age (<18 years and ≥ 18 years) and primary site (pelvic and non-pelvic), and randomized to receive 14 cycles of alternating vincristine-doxorubicin-cyclophosphamide and ifosfamide-etoposide given every 3 weeks (ST; Regimen A) vs. every 2 weeks (IC; Regimen B). For this updated report, one patient was excluded due to uncertainty of original diagnosis giving a total of 567 patients in this analysis. Data for tumor measurements and histologic response were collected retrospectively from institutional reports. EFS and overall survival (OS) were estimated using the Kaplan-Meier method and compared using the log-rank test and Gray’s test for cumulative incidence (CI). Results: The 10-year EFS for patients treated with IC chemo was 70% compared to 61% for ST chemo (p = 0.03), and the OS was 76% with IC chemo compared to 69% for ST chemo (p = 0.03). The 10-year CI of second malignant neoplasms (SMNs) for ST chemo was 4.2% [95% confidence interval: 2.4-7.5] compared to 3.2% (95% confidence interval: 1.6-6.3) for IC chemo (p = 0.5). There was a trend towards improved 10-year EFS in those receiving IC chemo both with non-pelvic (N = 477; 71% vs. 64%) and pelvic (N = 90; 67% vs. 43%) primary tumors. Similarly, the 10-year EFS was superior for patients treated with IC chemo in both the < 18 years (N = 500; 73% vs. 64%) and ≥ 18 years (N = 67; 53% vs. 37%) age groups. Among the 184 patients with available histologic response data, the 10-year EFS from the time of local control was 76% for those with < 10% viable tumor and 56% for those with ≥ 10% viable tumor (p = 0.01). Additional analysis comparing patients with any viable tumor vs. no viable tumor (NVT) by treatment regimen demonstrated that patients with NVT who received IC chemo had 10-year EFS and OS from local control of 91% and 97%, respectively. In the 210 patients for whom tumor volume calculations were possible, there was no difference in the 10-year EFS for patients with tumors < 200 mL vs. ≥ 200 mL. Conclusions: With longer term follow-up, IC chemotherapy for localized ES is associated with superior EFS and OS without an increase in SMNs. This study suggests patients ≥ 18 years with poor necrosis or pelvic primary tumors remain at high risk for relapse despite IC chemo, emphasizing the need for alternative treatment strategies to improve their outcomes. Clinical trial information: NCT00006734.

Phase 1/2 study of elraglusib (9-ING-41), a small molecule selective glycogen synthase kinase-3 beta (GSK-3β) inhibitor, alone or with irinotecan, temozolomide/irinotecan or cyclophosphamide/topotecan in pediatric patients with refractory malignancies: Interim results

e22015

Background: GSK-3β overexpression is associated with aggressive malignancies, treatment resistance and poor prognosis. The GSK-3β inhibitor Elraglusib induces apoptosis via NFΚB and p53 pathways and has potent anti-fibrotic and immunomodulatory activity. Adult studies of elraglusib demonstrate clinical activity in pancreatic cancer, melanoma, lymphoma and sarcoma as a single agent or in combination with cytotoxic chemotherapy. Elraglusib is active in in vivo models of neuroblastoma (NBL) and malignant glioma. This first-in-pediatrics study (NCT04239092) is evaluating the safety, pharmacokinetics (PK), and efficacy of elraglusib monotherapy and in combination with chemotherapy in patients with refractory malignancies. Methods: Elraglusib is given intravenously (IV) twice-weekly at 3 dose levels (DL) (9.3, 12.4 and 15 mg/kg) as a single agent or in combination with irinotecan, cyclophosphamide/topotecan or temozolomide/irinotecan in 21-day cycles. A cohort of pts with refractory NBL will be treated at the recommended phase 2 dose (RP2D) of elraglusib with temozolomide/irinotecan. Results: As of January 2022, 23 pts (n = 7 female, median age 14.2 years) have received at least one dose of elraglusib. Tumor types: 5 NBL, 3 diffuse midline glioma (DMG), 3 osteosarcoma (OS), 3 ependymoma (EP), 2 alveolar rhabdomyosarcoma (aRMS), 1 angiosarcoma (AS), 1 Ewing sarcoma (ES), 1 glioblastoma (GBM), 1 hepatoblastoma (HB), 1 embryonal CNS tumor NOS, 1 NUT midline carcinoma, 1 pineoblastoma (PB). Median time from diagnosis is 26 months (range: 6.7 – 156.3) and median number of lines of prior systemic therapy is 2 (range 0-14). Two DLs of single agent (6 pts) have been completed (9.3 and 12.4 mg/kg) without elraglusib-attributable severe adverse events (SAEs). Of the 15 patients on the combination arm with irinotecan or cyclophosphamide/topotecan, a single adverse event (Grade 4 hypotension/infusion reaction) was reported. Grade 1/2 elraglusib attributable-AEs include: transient visual change (n = 10), nausea (n = 7), vomiting (n = 6), fatigue (n = 2), hypotension (n = 2) and infusion reaction (n = 1). One pt with recurrent ES had a radiographic and pathologic CR after 3 cycles of elraglusib/cyclophosphamide/topotecan. 6 pts (26.1%) had SD (2 NBL, 1 aRMS, 1 EP, 1 OS, 1 GBM). 8 pts (35%) remained on study treatment ≥ 3 months (2 NBL, 2 EP, 1 OS, 1 aRMS, 1 ES, 1 PB). Median treatment duration was 40 days (range 1 - 126). 4 pts remain on therapy. Conclusions: Elraglusib is well tolerated as a single agent and with several chemotherapy regimens in this heavily pretreated pediatric population with refractory cancers. It has encouraging antitumor activity, with 1 CR in a patient with recurrent ES. Enrollment is ongoing; a RPD2 has not been reached. Clinical trial information: NCT04239092.

Phase I study of 131I-MIBG with dinutuximab for patients with relapsed or refractory neuroblastoma: A report from the new approaches to neuroblastoma therapy (NANT) consortium

10038

Background: 131I-metaiodobenzylguanidine (MIBG) is one of the most active salvage therapies for patients with relapsed or refractory (R/R) high-risk neuroblastoma (HRNB). Preclinical neuroblastoma studies show cooperative effects when radiation is combined with anti-GD2 monoclonal antibody (mAb). We hypothesized that MIBG would synergize with the anti-GD2 mAb dinutuximab to provide improved anti-tumor responses. The primary aims of Part A of this study were to determine the maximum tolerated dose (MTD) and/or recommended Phase II dose (RP2D) of MIBG administered with dinutuximab in children with R/R HRNB and to define and describe the toxicities. Methods: Patients 1-29 years of age with R/R HRNB who had MIBG uptake in ≥ 1 site were eligible. Prior anti-GD2 mAb therapy was allowed provided it was not administered with MIBG and not permanently discontinued due to toxicity. One prior MIBG therapy was allowed. MIBG was administered on day 1 at one of three dose levels (DLs): 12, 15, and 18 mCi/kg (DL1-DL3, respectively) with an expansion cohort at the RP2D. Doses were escalated using a rolling six design starting at DL1. The primary endpoint was dose-limiting toxicity (DLT) during course 1. Dinutuximab (17.5 mg/m2/dose) was administered intravenously on days 8-11 and 29-32 and GM-CSF (250 mcg/m2/dose) subcutaneously on days 8-17 and 29-38. Autologous peripheral blood stem cells were infused to all patients on day 15 (+/- 2 days). A maximum of 2 courses per patient were allowed. Response rate was defined as the proportion of patients with a complete or partial response. Results: Thirty-one patients were enrolled. Fourteen were evaluable for dose escalation (4 on DL1, 4 on DL2, and 6 on DL3); 5 evaluable patients were treated in the DL3 expansion. The median age was 7.4 years (range: 3.1 – 22.0) and 20 (65%) were male. Twenty-seven (87%) patients had previously received a median of 8.5 cycles of chemoimmunotherapy (range: 2 – 21). Eight patients previously progressed while receiving anti-GD2 mAb including 7 in DL3. Five (16%) patients had previously received MIBG. No patient at any dose level experienced DLT. Common grade 3/4 treatment-related toxicities were expected hematologic toxicities attributable to MIBG and non-hematologic toxicities attributable to dinutuximab or GM-CSF. Among 26 response-evaluable patients, the centrally-confirmed response rate was 31% across all dose levels: 2/6 (33%) in DL1, 3/5 (60%) in DL2, and 3/15 (20%) in DL3. There were 3 minor responses, 1 in DL2 and 2 in DL3. Conclusions: The RP2D of MIBG in combination with standard doses of dinutuximab and GM-CSF is 18 mCi/kg. This radioimmunotherapy regimen is well-tolerated without additive toxicity. Preliminary efficacy data are encouraging in this heavily pre-treated patient population. A phase 2 trial of this regimen is planned in patients with R/R HRNB. Clinical trial information: NCT03332667.

Comprehensive Genomic Profiling of High-Risk Pediatric Cancer Patients Has a Measurable Impact on Clinical Care

PURPOSE

Profiling of pediatric cancers through deep sequencing of large gene panels and whole exomes is rapidly being adopted in many clinical settings. However, the most impactful approach to genomic profiling of pediatric cancers remains to be defined.

METHODS

We conducted a prospective precision medicine trial, using whole-exome sequencing of tumor and germline tissue and whole-transcriptome sequencing (RNA Seq) of tumor tissue to characterize the mutational landscape of 127 tumors from 126 unique patients across the spectrum of pediatric brain tumors, hematologic malignancies, and extracranial solid tumors.

RESULTS

We identified somatic tumor alterations in 121/127 (95.3%) tumor samples and identified cancer predisposition syndromes on the basis of known pathogenic or likely pathogenic germline mutations in cancer predisposition genes in 9/126 patients (7.1%). Additionally, we developed a novel scoring system for measuring the impact of tumor and germline sequencing, encompassing therapeutically relevant genomic alterations, cancer-related germline findings, recommendations for treatment, and refinement of risk stratification or prognosis. At least one impactful finding from the genomic results was identified in 108/127 (85%) samples sequenced. A recommendation to consider a targeted agent was provided for 82/126 (65.1%) patients. Twenty patients ultimately received therapy with a molecularly targeted agent, representing 24% of those who received a targeted agent recommendation and 16% of the total cohort.

CONCLUSION

Paired tumor/normal whole-exome sequencing and tumor RNA Seq of de novo or relapsed/refractory tumors was feasible and clinically impactful in high-risk pediatric cancer patients.

Olecranon fractures: applied anatomy, clinical assessment and evidence-based management

Olecranon fractures are common injuries, making up 10% of all fractures of the upper limb. They usually result from a fall from standing height in older people, or from a direct blow in young people. The olecranon's superficial location, with poor soft tissue and muscle protection, make it liable to fracture following direct impact.

Factors such as the degree of initial force and the quality of the patient's bone result in a range of injury patterns, from simple undisplaced fractures to complex open fracture dislocations. In the context of high energy trauma, the patient should first be assessed for life-threatening injuries. A thorough history and clinical examination including neurovascular assessment should then be completed. Antero-posterior and lateral X-rays are sufficient to confirm the diagnosis. Initial management includes immobilisation in an above elbow backslab, a sling and analgesia.

Owing to the pull of the triceps muscle which attaches to the tip of the olecranon, fracture displacement is common and surgical intervention is often required, usually with good outcomes. Surgical techniques include tension band wiring, open reduction internal fixation with a pre-contoured locking plate and tension band suture fixation. Undisplaced fractures or displaced fractures in older patients can be managed conservatively with an above elbow cast for 4 weeks. This article covers applied anatomy, initial presentation, clinical assessment and evidence-based management.

Inhibition of the BTK-IDO-mTOR axis promotes differentiation of monocyte-lineage dendritic cells and enhances anti-tumor T cell immunity

Monocytic-lineage inflammatory Ly6c+CD103+ dendritic cells (DCs) promote antitumor immunity, but these DCs are infrequent in tumors, even upon chemotherapy. Here, we examined how targeting pathways that inhibit the differentiation of inflammatory myeloid cells affect antitumor immunity. Pharmacologic inhibition of Bruton's tyrosine kinase (BTK) and the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase (IDO) or deletion of Btk or Ido1 allowed robust differentiation of inflammatory Ly6c+CD103+ DCs during chemotherapy, promoting antitumor T cell responses and inhibiting tumor growth. Immature Ly6c+c-kit+ precursor cells had epigenetic profiles similar to conventional DC precursors; deletion of Btk or Ido1 promoted differentiation of these cells. Mechanistically, a BTK-IDO axis inhibited a tryptophan-sensitive differentiation pathway driven by GATOR2 and mTORC1, and disruption of the GATOR2 in monocyte-lineage precursors prevented differentiation into inflammatory DCs in vivo. IDO-expressing DCs and monocytic cells were present across a range of human tumors. Thus, a BTK-IDO axis represses differentiation of inflammatory DCs during chemotherapy, with implications for targeted therapies.

A phase 1 study of prexasertib (LY2606368), a CHK1/2 inhibitor, in pediatric patients with recurrent or refractory solid tumors, including CNS tumors: A report from the Children's Oncology Group Pediatric Early Phase Clinical Trials Network (ADVL1515)

BACKGROUND

Prexasertib (LY2606368) is a novel, second-generation, selective dual inhibitor of checkpoint kinase proteins 1 (CHK1) and 2 (CHK2). We conducted a phase 1 trial of prexasertib to estimate the maximum-tolerated dose (MTD) and/or recommended phase 2 dose (RP2D), to define and describe the toxicities, and to characterize the pharmacokinetics (PK) of prexasertib in pediatric patients with recurrent or refractory solid and central nervous system (CNS) tumors.

METHODS

Prexasertib was administered intravenously (i.v.) on days 1 and 15 of a 28-day cycle. Four dose levels, 80, 100, 125, and 150 mg/m² , were evaluated using a rolling-six design. PK analysis was performed during cycle 1. Tumor tissue was examined for biomarkers (CHK1 and TP53) of prexasertib activity.

RESULTS

Thirty patients were enrolled; 25 were evaluable. The median age was 9.5 years (range: 2-20) and 21 (70%) were male. Twelve patients (40%) had solid tumors and 18 patients (60%) had CNS tumors. There were no cycle 1 or later dose-limiting toxicities. Common cycle 1, drug-related grade 3/4 toxicities (> 10% of patients) included neutropenia (100%), leukopenia (68%), thrombocytopenia (24%), lymphopenia (24%), and anemia (12%). There were no objective responses; best overall response was stable disease in three patients for five cycles (hepatocellular carcinoma), three cycles (ependymoma), and five cycles (undifferentiated sarcoma). The PK appeared dose proportional across the 80-150 mg/m² dose range.

CONCLUSIONS

Although the MTD of prexasertib was not defined by this study, 150 mg/m² administered i.v. on days 1 and 15 of a 28-day cycle was determined to be the RP2D.

Phase II study of nivolumab and ipilimumab in children and young adults with INI1-negative cancers

TPS10055

Background: Several aggressive pediatric and young adult cancers are characterized by SMARCB1 inactivation resulting in loss of INI1 expression, including rhabdoid tumors, epithelioid sarcoma and undifferentiated chordoma. These malignancies are associated with a poor prognosis and few effective treatment options for relapsed or refractory disease. Prior studies and emerging data suggest INI1-negative cancers may be uniquely susceptible to treatment with immune checkpoint inhibitors: Many INI1-negative pediatric tumors express PD-L1 and are infiltrated by immune cells, and there are reports of patients with advanced INI1-negative cancers with clinical responses to immune checkpoint blockade (Forrest et al. Clinical Cancer Research, 2020). We hypothesize that INI1 loss predicts tumor response to immune checkpoint inhibition (ICI). Methods: This is an ongoing multicenter, phase II, open-label clinical trial to evaluate the activity of nivolumab and ipilimumab in patients aged 6 months to 30 years with relapsed or refractory INI1-negative cancers (NCT04416568). The study enrolls patients in 2 strata: extracranial solid tumors in Stratum 1 and intracranial solid tumors in Stratum 2. Patients treated with prior ICI are excluded. Patients are treated with intravenous (IV) nivolumab 3mg/kg plus ipilimumab 1mg/kg IV every 3 weeks for 4 cycles followed by nivolumab 3mg/kg (max dose 240mg) IV every 2 weeks for up to 1-year. The primary objective is to evaluate the objective response rate (ORR) by Response Evaluation Criteria in Solid Tumors (RECIST) for Stratum 1 and by Response Assessment in Neuro-Oncology (RANO) criteria for Stratum 2. The trial has a 2-stage design targeting a 25% or greater response rate, with each stratum assessed independently. The analysis for Stage 1 in a given Stratum will be performed after 10 patients are enrolled. If a sufficient number of responders are observed, an additional 10 patients will be enrolled at Stage 2. Secondary endpoints include progression-free survival, overall survival, and disease control rate at 12 months. Correlative aims include assessing tissue and blood biomarkers associated with treatment response. Enrollment began 14 Aug 2020 and is ongoing. Clinical trial information: NCT04416568.

Coronavirus infection in hip fractures (CHIP) study

AIMS

Despite the COVID-19 pandemic, incidence of hip fracture has not changed. Evidence has shown increased mortality rates associated with COVID-19 infection. However, little is known about the outcomes of COVID-19 negative patients in a pandemic environment. In addition, the impact of vitamin D levels on mortality in COVID-19 hip fracture patients has yet to be determined.

METHODS

This multicentre observational study included 1,633 patients who sustained a hip fracture across nine hospital trusts in North West England. Data were collected for three months from March 2020 and for the same period in 2019. Patients were matched by Nottingham Hip Fracture Score (NHFS), hospital, and fracture type. We looked at the mortality outcomes of COVID-19 positive and COVID-19 negative patients sustaining a hip fracture. We also looked to see if vitamin D levels had an impact on mortality.

RESULTS

The demographics of the 2019 and 2020 groups were similar, with a slight increase in proportion of male patients in the 2020 group. The 30-day mortality was 35.6% in COVID-19 positive patients and 7.8% in the COVID-19 negative patients. There was a potential association of decreasing vitamin D levels and increasing mortality rates for COVID-19 positive patients although our findings did not reach statistical significance.

CONCLUSION

In 2020 there was a significant increase in 30-day mortality rates of patients who were COVID-19 positive but not of patients who were COVID-19 negative. Low levels of vitamin D may be associated with high mortality rates in COVID-19 positive patients. Cite this article: Bone Joint J 2021;103-B(4):782-787.

HGG-01. ENTRECTINIB IN RECURRENT OR REFRACTORY SOLID TUMORS INCLUDING PRIMARY CNS TUMORS: UPDATED DATA IN CHILDREN AND ADOLESCENTS

STARTRK-NG (phase 1/2) is evaluating entrectinib, a CNS-penetrant oral, TRK/ROS1/ALK tyrosine kinase inhibitor, in patients <21 years with recurrent/refractory solid tumors, including primary CNS tumors. After determining the recommended dose, 550mg/m²/day, in all-comers, expansion cohorts with gene-fusion-positive CNS/solid tumors (NTRK1/2/3, ROS1) are being enrolled. As of 5Nov2019 (data cut-off), 39 patients (4.9m–20y; median 7y) have been evaluated for response, classified as complete (CR) or partial response (PR), stable (SD) or progressive disease (PD) using RANO (CNS), RECIST (solid tumors), or Curie score (neuroblastoma). Responses in patients with fusion-positive tumors were Investigator-assessed (BICR assessments are ongoing) and occurred at doses ≥400mg/m². Best responses in fusion-positive CNS tumors (n=14) were: 4 CR (GKAP1-NTRK2, ETV6-NTRK3 [n=2], EML1-NTRK2); 5 PR (KANK1-NTRK2, GOPC-ROS1, ETV6-NTRK3, TPR-NTRK1, EEF1G-ROS1); 3 SD (BCR-NTRK2, ARHGEF2-NTRK1, KIF21B-NTRK1); 2 PD (PARP6-NTRK3, EML4-ALK); and in fusion-positive solid tumors (n=8) were: 3 CR (ETV6-NTRK3 [n=2], DCTN1-ALK); 5 PR (EML4-NTRK3, TFG-ROS1 [n=3], KIF5B-ALK). Responses (Investigator-assessed) in non-fusion tumors (n=17) were: 1 CR (ALK F1174L mutation), 3 SD, 10 PD, 3 no data/unevaluable. The objective response rate (CR+PR/total) in patients with fusion-positive tumors was 77% (17/22) versus 6% (1/17) in those with non-fusion tumors. All 39 patients experienced ≥1 adverse event (AE); the most frequent AEs included weight gain and anemia (both 48.7%); increased ALT, increased AST, cough and pyrexia (all 46.2%); increased creatinine and vomiting (both 43.6%); and bone fractures (n=10, in 9 patients). Entrectinib has produced striking, rapid, and durable responses in solid tumors with target gene fusions, especially high-grade CNS neoplasms.

Limited implementation of measures to reduce nosocomial spread of COVID-19 in hip-fracture patients in the North West of England

Hip-fracture patients are vulnerable to the outcomes of COVID-19. We performed a cross-sectional survey to determine measures employed to limit nosocomial spread of COVID-19 in 23 orthopaedic trauma departments in the North-West of England. Nineteen (87%) hospitals admitted patients to a ward prior to a negative swab, and only 9 (39%) patients were barrier nursed. Hip-fracture patients were operated in non-COVID-19-free theatres in 21 (91%) hospitals. Regular screening of doctors working in trauma and elective areas for COVID-19 was undertaken in three (13%) and five (22%) hospitals, respectively. Doctors moved freely between trauma and elective areas in 22 (96%) hospitals.

Updated entrectinib data in children and adolescents with recurrent or refractory solid tumors, including primary CNS tumors

107

Background: The phase 1/2 STARTRK-NG trial (NCT02650401) is evaluating entrectinib, a CNS-penetrant oral inhibitor of TRK, ROS1 and ALK tyrosine kinases, in children and adolescents < 21 years old with recurrent/refractory solid tumors, including primary CNS tumors. Methods: After determining the recommended dose as 550mg/m2/day in all-comers, expansion cohorts with gene-fusion-positive CNS/solid tumors ( NTRK1/2/3 and ROS1) are being enrolled. Results: As of 1 July 2019 (data cut-off), 34 patients (4.9 months to 20 years old; median age 7 years) have been evaluated for response to treatment with entrectinib. Responses were classified as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD) using RANO for CNS tumors, RECISTv1.1 for solid tumors, or Curie score for neuroblastomas. Responses in fusion-positive patients were assessed by blinded independent central review (BICR), and occurred at doses ≥400mg/m2. Best responses in patients with fusion-positive CNS tumors (n = 8) were four CR ( ETV6-NTRK3, EML1-NTRK2, GOPC-ROS1, and TPR-NTRK1), two PR ( KANK1-NTRK2 and EEF1G-ROS1), and two PD ( EML4-ALK and PARP6-NTRK3). In patients with fusion-positive solid tumors (n = 6) best responses were three CR ( DCTN1-ALK, ETV6-NTRK3, and ETV6-NTRK3), and three PR ( TFG-ROS1, EML4-NTRK3, and KIF5B-ALK). Responses (Investigator-assessed) in patients with non-fusion tumors (n = 20) were one CR ( ALK F1174L mutation), four SD, ten PD, and five patients were unevaluable or had no data. The objective response rate (defined as the total number of CR and PR) in fusion-positive patients was 86% (12/14) versus 5% (1/20) in non-fusion patients. Similarly, PFS was 17.5 months (95% CI 7.4–NE) in fusion-positive patients versus 1.9 months (1.8–5.7; p = 0.0002) in non-fusion patients. Most commonly reported treatment-related adverse events included weight gain (n = 14 [5 Grade 3/4]), elevated creatinine (n = 13), anemia (n = 13), nausea (n = 11), increased ALT (n = 10 [1 Grade 3/4]), increased AST (n = 10 [1 Grade 3/4]), decreased neutrophils (n = 9 [6 Grade 3/4]), and bone fractures (n = 7, of which 4 were treatment related). Conclusions: In children and adolescents < 21 years old, entrectinib has produced striking, rapid, and durable responses in solid tumors with target gene fusions, especially in high-grade CNS neoplasms. Clinical trial information: NCT02650401.

A phase I study of simvastatin in combination with topotecan and cyclophosphamide in pediatric patients with relapsed and/or refractory solid and CNS tumors

10541

Background: HMG-CoA reductase inhibitors (statins) can inhibit IL-6-mediated STAT3 activation, a critical pathway in pediatric CNS and solid tumors. Statins also inhibit tumor proliferation, angiogenesis, and restore apoptosis in preclinical pediatric solid tumor models. We therefore conducted a phase 1 trial of simvastatin in combination with topotecan and cyclophosphamide in children with relapsed/refractory (r/r) solid and CNS tumors. Methods: Eligible patients were 1-29 years of age with a r/r solid or CNS tumor. Simvastatin was administered orally twice daily on days 1-21, with topotecan 0.75 mg/m2/dose IV and cyclophosphamide 250 mg/m2/dose IV on days 1-5. Four dose levels (DLs) were planned: 140, 180, 225, 290 mg/m2/dose. A 3+3 design was used to determine the maximum tolerated dose (MTD). Pharmacokinetic and pharmacodynamic analyses were performed. Results: The median (range) age of 14 eligible patients was 11.5 years (1 - 23). Diagnoses included neuroblastoma (N = 4), sarcoma (N = 7), and one each of malignant rhabdoid tumor of kidney, medulloblastoma, and Wilms tumor. Eleven DLT-evaluable patients received a median of 4 cycles (range: 1-6). There were 3 cycle 1 DLTs, grade 3 diarrhea and grade 4 creatine phosphokinase (CPK) increased at DL 1, and grade 4 CPK increased at DL 0 (100 mg/m2/dose). Grade 3/4 treatment-related cycle 1 adverse events occurring in ≥ 10% patients were neutropenia (100%), leukopenia (100%), thrombocytopenia (91%), lymphopenia (91%), anemia (55%), febrile neutropenia (55%) and CPK increased (18%). Best overall response was partial response in 1 patient and stable disease in four. Simvastatin and simvastatin acid Cmax (geomean 82.5 and 12.6 ng/mL) and AUC0-6 (geomean 82.5 and 12.6 ng•h/mL) were comparable with reported pediatric literature values (Cmax 3.5 and 0.4-2.1 ng/mL; AUC0-8 10.7 and 3.8 ng•h/mL) after correction for the higher doses (3.77 vs 0.16 mg/kg) used in our study. Patient peripheral blood mononuclear cells showed maximum phospho-(p)STAT3 inhibition on Day 5, with recurrence by Day 21 despite continued simvastatin dosing. Plasma IL6 levels showed sustained IL6 inhibition with decrease to normal values by Day 21 in all patients, indicating potential on target effects. Conclusions: For this first-in-pediatrics trial of statins as anti-cancer therapy, the MTD of simvastatin with chemotherapy was 100 mg/m2/dose. This combination was well-tolerated with predominantly hematologic toxicity and predictable DLTs related to simvastatin. Clinical trial information: NCT02390843.

A phase I study of sirolimus in combination with metronomic therapy (CHOAnome) in children with recurrent or refractory solid and brain tumors

BACKGROUND/PURPOSE

To determine the maximum tolerated dose, toxicities, and response of sirolimus combined with oral metronomic therapy in pediatric patients with recurrent and refractory solid and brain tumors.

PROCEDURE

Patients younger than 30 years of age with recurrent, refractory, or high-risk solid and brain tumors were eligible. Patients received six-week cycles of sirolimus with twice daily celecoxib, and alternating etoposide and cyclophosphamide every three weeks, with Bayesian dose escalation over four dose levels (NCT01331135).

RESULTS

Eighteen patients were enrolled: four on dose level (DL) 1, four on DL2, eight on DL3, and two on DL4. Diagnoses included solid tumors (Ewing sarcoma, osteosarcoma, malignant peripheral nerve sheath tumor, rhabdoid tumor, retinoblastoma) and brain tumors (glioblastoma multiforme [GBM], diffuse intrinsic pontine glioma, high-grade glioma [HGG], medulloblastoma, ependymoma, anaplastic astrocytoma, low-grade infiltrative astrocytoma, primitive neuroectodermal tumor, nongerminomatous germ cell tumor]. One dose-limiting toxicity (DLT; grade 4 neutropenia) was observed on DL2, two DLTs (grade 3 abdominal pain and grade 3 mucositis) on DL3, and two DLTs (grade 3 dehydration and grade 3 mucositis) on DL4. The recommended phase II dose of sirolimus was 2 mg/m² (DL3). Best response was stable disease (SD) in eight patients, and partial response (PR) in one patient with GBM. A patient with HGG was removed from the study with SD and developed PR without further therapy. Western blot analysis showed inhibition of phospho-S6 kinase in all patients during the first cycle of therapy.

CONCLUSION

The combination of sirolimus with metronomic chemotherapy is well tolerated in children. A phase II trial of this combination is ongoing.

Routine Surveillance Imaging Is Associated with Improved Postrelapse Survival in Patients with Ewing Sarcoma

Purpose: Children with Ewing sarcoma (ES) routinely undergo surveillance imaging after completion of therapy; however, the medical benefit of this imaging remains unclear. We aimed to determine whether there is a difference in survival between patients whose relapse was detected based on development of new symptoms or by routine imaging. Methods: We retrospectively reviewed all patients consecutively diagnosed with ES at Children's Healthcare of Atlanta from 2000 to 2011. Patient characteristics and outcomes were compared based on whether their relapse was diagnosed based on symptoms or by routine surveillance imaging alone. Results: Thirty-three percent (28/85) of patients relapsed. Median age at time of relapse was 15.5 years (interquartile range: 12.5-18.0). Among the relapsed patients, 57% (16/28) were symptomatic and 43% (12/28) were asymptomatic, having relapse detected on surveillance imaging alone. The most common presenting symptom was bone pain occurring in 69% (11/16) of patients. The 5-year postrelapse overall survival for patients with symptomatic relapse was 0% (95% confidence interval [CI]: not estimated) compared with 15% (95% CI: 1-48) for patients with an asymptomatic relapse (p < 0.01). After adjusting for extent of disease and time to relapse, having a symptomatic relapse was still strongly associated with a worse outcome (hazard ratio: 9.68; 95% CI: 3.09-30.34). Conclusion: Patients with ES whose relapse is detected on imaging before the development of symptoms have significantly better outcomes, suggesting a potentially beneficial role of routine surveillance imaging in this population of patients. Further prospective analyses are needed to confirm these findings, and determine the optimal evidence-based imaging modality and schedule.

Abstract C002: Phase 1 study of abemaciclib in children with recurrent and refractory solid tumors including malignant brain tumors

Background: Cyclin-dependent kinases 4 and 6 (CDK4/6) control the transition between G1 and S phases of the cell cycle and are dysregulated in a number of pediatric brain and solid tumors. Abemaciclib, a selective and potent small molecule CDK4/6 inhibitor that crosses the blood brain barrier, limits cell proliferation by suppressing phosphorylation of RB, leading to G1 arrest. Methods: We conducted a phase 1 trial of abemaciclib to determine the maximum tolerated dose (MTD), describe toxicities, and pharmacokinetic (PK) parameters of abemaciclib in pediatric patients with recurrent or refractory solid and CNS tumors. A stratum for newly diagnosed patients with diffuse midline glioma continues to enroll. A CDK mutation was not required, and patients with known RB1 mutations were excluded. Abemaciclib was administered orally twice daily on days 1-28 of a 28-day cycle. Four dose levels were planned (100, 130, 170, and 220 mg/m2/dose) and evaluated using a rolling-six design. Patients were enrolled to a dose expansion cohort at the MTD to ensure adequate PK sampling and safety. PK and pharmacodynamic (PD) analyses are ongoing. Results: The median age of 34 eligible patients was 13.8 years (range: 2.9 - 23.2). Seven (21%) patients had a solid tumor [osteosarcoma (N=2), neuroblastoma (N=1), rhabdomyosarcoma (N=1), desmoplastic small round cell tumor (N=1), clear cell sarcoma (N=1), and MRT of kidney (N=1)] and 27 (79%) patients had a malignant brain tumor [high-grade glioma (N=12), DIPG (N=5), ATRT (N=3), medulloblastoma (N=3), ependymoma (N=2), PNET (N=1), and CNS neuroblastoma (N=1)]. Twenty-three patients were evaluable for DLT. There were 2 cycle 1 DLTs, grade 4 thrombocytopenia and grade 3 vomiting and diarrhea, both occurring at dose level 3. The most common treatment-related cycle 1 adverse events were leukopenia (69%), neutropenia (53%), thrombocytopenia (44%), hypoalbuminemia (41%), anemia (38%), hypophosphatemia (34%) and diarrhea (34%). Conclusions: The pediatric MTD of abemaciclib was 130 mg/m2/dose administered orally twice daily on a 28-day cycle. Abemaciclib was well-tolerated with mainly hematologic toxicity. PK and PD will be used to further inform if 130 mg/m2/dose is the pediatric recommended phase 2 dose.

Citation Format: Thomas Cash, Dolly Aguilera, Margaret E Macy, Lindsey Hoffman, Kathleen Dorris, Courtney McCracken, Bradley Hanberry, Robert Castellino, Tobey MacDonald, Cynthia Wetmore. Phase 1 study of abemaciclib in children with recurrent and refractory solid tumors including malignant brain tumors [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C002. doi:10.1158/1535-7163.TARG-19-C002

Provocative questions in osteosarcoma basic and translational biology: A report from the Children's Oncology Group

Patients who are diagnosed with osteosarcoma (OS) today receive the same therapy that patients have received over the last 4 decades. Extensive efforts to identify more effective or less toxic regimens have proved disappointing. As we enter a postgenomic era in which we now recognize OS not as a cancer of mutations but as one defined by p53 loss, chromosomal complexity, copy number alteration, and profound heterogeneity, emerging threads of discovery leave many hopeful that an improving understanding of biology will drive discoveries that improve clinical care. Under the organization of the Bone Tumor Biology Committee of the Children's Oncology Group, a team of clinicians and scientists sought to define the state of the science and to identify questions that, if answered, have the greatest potential to drive fundamental clinical advances. Having discussed these questions in a series of meetings, each led by invited experts, we distilled these conversations into a series of seven Provocative Questions. These include questions about the molecular events that trigger oncogenesis, the genomic and epigenomic drivers of disease, the biology of lung metastasis, research models that best predict clinical outcomes, and processes for translating findings into clinical trials. Here, we briefly present each Provocative Question, review the current scientific evidence, note the immediate opportunities, and speculate on the impact that answered questions might have on the field. We do so with an intent to provide a framework around which investigators can build programs and collaborations to tackle the hardest problems and to establish research priorities for those developing policies and providing funding.

Gemcitabine/nab-paclitaxel for pediatric relapsed/refractory sarcomas

BACKGROUND

Pediatric patients with relapsed/refractory sarcomas have poor outcomes and need novel therapies that provide disease control while maintaining an acceptable quality of life. The activity and toxicity of gemcitabine and nab-paclitaxel in combination has not been reported in pediatrics.

PROCEDURE

We reviewed the records of fifteen relapsed/refractory patients and one treatment-naïve patient who received gemcitabine/nab-paclitaxel at our institution.

RESULTS

Sixteen patients (median age 13.5 years, range 3-19 years) received 53 cycles of gemcitabine/nab-paclitaxel. Twenty-nine cycles (55%) resulted in ≥Grade 3 toxicity, with nonhematologic Grade ≥3 toxicities occurring in only eight of 53 cycles (15%). Patients received red blood cell and platelet transfusions in 23% and 4% of cycles, respectively. Grade ≥3 infectious toxicities occurred in 4% of cycles. Of 14 patients with measurable disease, there were no complete responses (CR), one partial response (PR; 7%), and six patients (43%) with stable disease (SD; median SD: 4.5 months, range: 2-19 months). In total, 31% of the patients derived clinical benefit (CR + PR + SD ≥ 4 months). Median time to progression was 72 days with a 4-month progression-free survival of 31% ± 12% and 1-year overall survival of 19% ± 10%. With a median follow-up for all 16 patients of 21 months from the first treatment with gemcitabine/nab-paclitaxel, one (6%) remains alive with disease.

CONCLUSIONS

Gemcitabine/nab-paclitaxel is a relatively safe regimen with mainly hematologic toxicities. It offers a well-tolerated, palliative option providing clinical benefit in a subset of patients. A phase I trial of this combination is underway.

Successful Use of Extracorporeal Life Support in a Hematopoietic Stem Cell Transplant Patient with Neuroblastoma

Respiratory failure associated with hematopoietic stem cell transplantation (HSCT) has been considered a contraindication for use of extracorporeal membrane oxygenation (ECMO) at many centers. We describe a child with neuroblastoma and hypoxemic respiratory failure following HSCT who was successfully managed with veno-venous (VV) ECMO. The patient was an 18-month-old female with high-risk neuroblastoma status post tumor resection, chemotherapy, autologous HSCT, and primary site radiation. On day 113 posttransplant while receiving maintenance immunotherapy, she had an acute respiratory decompensation because of rhinovirus, aspiration pneumonia, and capillary leak syndrome. The patient was intubated and transitioned to a high frequency oscillatory ventilation and inhaled nitric oxide. Because of refractory hypoxemia, she was cannulated for VV ECMO. She was weaned and decannulated after 7.5 days on ECMO, then subsequently transferred for inpatient rehabilitation. The most recent Extracorporeal Life Support Organization registry analysis showed low survival (3/29) in patients requiring ECMO after HSCT, and 2 of 3 survivors had nononcological diagnoses. However, our patient's outcome suggests that HSCT status should not be an absolute contraindication. The presence of a reversible single organ failure and the absence of significant bleeding risk in an engrafted, neurologically intact, and non-neutropenic HSCT patient with a favorable prognosis can support the potential benefit of ECMO.

Respiratory Difficulties in Children With Underlying Asthma During Immunotherapy for High-risk Neuroblastoma

Treatment of high-risk neuroblastoma now includes antibody based antitumor immunotherapy as part of standard care. Although this therapy has resulted in dramatic improvements in survival, it is associated with significant side effects. Children with underlying respiratory issues, and in particular asthma, may be more susceptible to immunotherapy associated respiratory compromise and pulmonary complications. Early routine involvement of pulmonology care is warranted for these patients in an effort to allow maximal delivery of immunotherapy and minimize acute and long-term complications.

A Phase I Study of the CDK4/6 Inhibitor Ribociclib (LEE011) in Pediatric Patients with Malignant Rhabdoid Tumors, Neuroblastoma, and Other Solid Tumors

Purpose: The cyclin-dependent kinase (CDK) 4/6 inhibitor, ribociclib (LEE011), displayed preclinical activity in neuroblastoma and malignant rhabdoid tumor (MRT) models. In this phase I study, the maximum tolerated dose (MTD) and recommended phase II dose (RP2D), safety, pharmacokinetics (PK), and preliminary activity of single-agent ribociclib were investigated in pediatric patients with neuroblastoma, MRT, or other cyclin D-CDK4/6-INK4-retinoblastoma pathway-altered tumors.Experimental Design: Patients (aged 1-21 years) received escalating once-daily oral doses of ribociclib (3-weeks-on/1-week-off). Dose escalation was guided by a Bayesian logistic regression model with overdose control and real-time PK.Results: Thirty-two patients (median age, 5.5 years) received ribociclib 280, 350, or 470 mg/m² Three patients had dose-limiting toxicities of grade 3 fatigue (280 mg/m²; n = 1) or grade 4 thrombocytopenia (470 mg/m²; n = 2). Most common treatment-related adverse events (AE) were hematologic: neutropenia (72% all-grade/63% grade 3/4), leukopenia (63%/38%), anemia (44%/3%), thrombocytopenia (44%/28%), and lymphopenia (38%/19%), followed by vomiting (38%/0%), fatigue (25%/3%), nausea (25%/0%), and QTc prolongation (22%/0%). Ribociclib exposure was dose-dependent at 350 and 470 mg/m² [equivalent to 600 (RP2D)-900 mg in adults], with high interpatient variability. Best overall response was stable disease (SD) in nine patients (seven with neuroblastoma, two with primary CNS MRT); five patients achieved SD for more than 6, 6, 8, 12, and 13 cycles, respectively.Conclusions: Ribociclib demonstrated acceptable safety and PK in pediatric patients. MTD (470 mg/m²) and RP2D (350 mg/m²) were equivalent to those in adults. Observations of prolonged SD support further investigation of ribociclib combined with other agents in neuroblastoma and MRT. Clin Cancer Res; 23(10); 2433-41. ©2017 AACR.

Comparison of clinical features and outcomes in patients with extraskeletal versus skeletal localized Ewing sarcoma: A report from the Children's Oncology Group

BACKGROUND

The prognostic significance of having extraskeletal (EES) versus skeletal Ewing sarcoma (ES) in the setting of modern chemotherapy protocols is unknown. The purpose of this study was to compare the clinical characteristics, biologic features, and outcomes for patients with EES and skeletal ES.

METHODS

Patients had localized ES and were treated on two consecutive protocols using five-drug chemotherapy (INT-0154 and AEWS0031). Patients were analyzed based on having an extraskeletal (n = 213) or skeletal (n = 826) site of tumor origin. Event-free survival (EFS) was estimated using the Kaplan-Meier method, compared using the log-rank test, and modeled using Cox multivariate regression.

RESULTS

Patients with extraskeletal ES (EES) were more likely to have axial tumors (72% vs. 55%; P < 0.001), less likely to have tumors >8 cm (9% vs. 17%; P < 0.01), and less likely to be white (81% vs. 87%; P < 0.001) compared to patients with skeletal ES. There was no difference in key genomic features (type of EWSR1 translocation, TP53 mutation, CDKN2A mutation/loss) between groups. After controlling for age, race, and primary site, EES was associated with superior EFS (hazard ratio = 0.69; 95% confidence interval: 0.50-0.95; P = 0.02). Among patients with EES, age ≥18, nonwhite race, and elevated baseline erythrocyte sedimentation rate were independently associated with inferior EFS.

CONCLUSION

Clinical characteristics, but not key tumor genomic features, differ between EES and skeletal ES. Extraskeletal origin is a favorable prognostic factor, independent of age, race, and primary site.

Near-peer medical student simulation training

BACKGROUND

There is growing concern that medical students are inadequately prepared for life as a junior doctor. A lack of confidence managing acutely unwell patients is often cited as a barrier to good clinical care. With medical schools investing heavily in simulation equipment, we set out to explore if near-peer simulation training is an effective teaching format.

METHODS

Medical students in their third year of study and above were invited to attend a 90-minute simulation teaching session. The sessions were designed and delivered by final-year medical students using clinical scenarios mapped to the Sheffield MBChB curriculum. Candidates were required to assess, investigate and manage an acutely unwell simulated patient. Pre- and post-simulation training Likert scale questionnaires were completed relating to self-reported confidence levels. There is growing concern that medical students are inadequately prepared for life as a junior doctor RESULTS: Questionnaires were completed by 25 students (100% response rate); 52 per cent of students had no prior simulation experience. There were statistically significant improvements in self-reported confidence levels in each of the six areas assessed (p < 0.005). Thematic analysis of free-text comments indicated that candidates enjoyed the practical format of the sessions and found the experience useful.

DISCUSSION

Our results suggest that near-peer medical student simulation training benefits both teacher and learner and that this simplistic model could easily be replicated at other medical schools. As the most junior members of the team, medical students are often confined to observer status. Simulation empowers students to practise independently in a safe and protected environment. Furthermore, it may help to alleviate anxiety about starting work as a junior doctor and improve future patient care.

Clinical features and outcomes of infants with Ewing sarcoma under 12 months of age

BACKGROUND

Ewing sarcoma peaks in incidence in adolescence. Infants <12 months old have rarely been reported. We aimed to compare clinical features, treatment, and survival of infants <12 months to those of older pediatric patients with Ewing sarcoma.

PROCEDURE

We utilized the SEER database to identify patients <12 months of age diagnosed with Ewing sarcoma between 1973 and 2011. We used Fisher exact tests to compare clinical features and treatment modalities between these patients and patients aged 1-19 years. We used Kaplan-Meier methods to describe overall survival in these two groups.

RESULTS

Of 1,957 patients in the cohort, 39 (2.0%) were diagnosed at <12 months of age. Infants had a different distribution of primary tumor sites, with lower extremity tumors under represented. Compared to older patients, infants were more likely to have soft tissue tumors (81.6% vs. 27.1%; P < 0.001); have primitive neuroectodermal tumor/Askin tumor (61.5% vs. 19.9%; P < 0.001); and have tumors <8 cm (81.0% vs. 53.2%; P < 0.014). Infants were less likely to receive radiation therapy (13.2% vs. 53.3%; P < 0.001). Infants were at increased risk for early death (P < 0.013 by Wilcoxon), though long-term overall survival was not different between age groups (P < 0.25 by log rank).

CONCLUSIONS

Ewing sarcoma is rare in infants, with different clinical presentations and treatment approaches. These patients appear to be at higher risk for early death, but long-term survival is similar to older pediatric patients.

Comparison of survival at adult versus pediatric treatment centers for rare pediatric tumors in an adolescent and young adult (AYA) population in the State of Georgia

BACKGROUND

The type of treatment center where 15-21-year-old adolescent and young adult (AYA) patients with rare pediatric tumors achieve their best clinical outcome is unknown.

PROCEDURE

We performed a retrospective analysis using the Georgia Cancer Registry (GCR) of 15-21-year old patients with a malignant, rare pediatric tumor diagnosed during the period from 2000-2009. Patients were identified as being treated at one of five Georgia pediatric cancer centers or at an adult center. Data were analyzed for 10 year overall survival, patient characteristics associated with death, and patient characteristics present at diagnosis associated with choice of treatment center.

RESULTS

There was a total of 479 patients in our final study population, of which 379 (79.1%) were treated at an adult center and 100 (20.9%) were treated at a pediatric center. Patients treated at an adult center had a 10 year overall survival of 86% compared to 85% for patients treated at a pediatric center (P = 0.31). Race and poverty were not significantly associated with death. Patients with nasopharyngeal carcinoma (OR = 7.38; 95% CI = 2.30-23.75) and 'other carcinomas' (OR = 2.64; 95% CI = 1.25-5.60) were more likely to be treated at a pediatric center. Patients with higher-stage disease (OR = 4.24; 95% CI = 1.71-10.52) and higher poverty (OR = 2.32; 95% CI = 1.23-4.37) were also more likely to be treated at a pediatric center.

CONCLUSION

Our data suggest that there is no difference in survival for 15-21-year old patients with rare pediatric tumors when treated at an adult or pediatric center.

The contributors of emotional distress in painful diabetic neuropathy

AIMS

To examine the contribution of demographic, social, clinical and psychological factors to emotional distress in patients with painful diabetic neuropathy (DN).

METHODS

In total, 142 patients with confirmed painful DN underwent detailed clinical and self-assessment measures (Neuropathic Pain Scale, Hospital Anxiety and Depression Scale, Pain Acceptance Questionnaire and Pain Catastrophizing Scale).

RESULTS

The prevalence of emotional distress was 51.4% in this cohort. Age, sex, marital status, employment history, pain intensity, duration of diabetes and the presence of diabetic and non-diabetic complications were significantly correlated to anxiety and depressive symptom scores. Multiple regression analysis confirmed that the presence of catastrophic thinking was an independent contributor to greater symptoms of anxiety and depression. Being young, single and unemployed significantly contributed to greater anxiety symptoms. Pain-related restriction of quality of life was associated with greater depression symptom scores.

CONCLUSIONS

This study found a high prevalence of emotional distress in patients with painful DN. It highlights that the differing independent contributors to anxiety and depressive symptoms are based on an individual's circumstances and experience. We conclude by highlighting the importance of adopting a holistic approach to pain management, incorporating interventions to increase psychological flexibility alongside conventional pharmacological treatments to improve emotional distress in painful DN.

An investigation of angiotensin II agonist and antagonist analogues with 5,5-dimethylthiazolidine-4-carboxylic acid and other constrained amino acids

To probe the receptor-bound conformational requirements of angiotensin II (ANG II) octapeptide agonists and antagonists, the synthesis and biological activities of [Sar1]ANG II agonist and [Sar1,X8]ANG II antagonist analogues (X8 = Ile, D-Phe, or Aib) bearing conformational constraints in positions 3, 5, and 7 were investigated and compared with previous literature efforts. The conformational constraints that were examined include Pro, Dtc (5,5-dimethylthiazolidine-4-carboxylic acid), Aib, Cle, (NMe)Ala, (NMe)Ile, and the lactam modification, L,L-lactam-Phe, previously described by Freidinger et al. (J. Org. Chem. 1982, 47, 104-109). Both [Sar1,(NMe)Ala3 and Pro3]ANG II retained agonist activity, while only [Sar1,(NMe)Ala3,Ile8]ANG II retained antagonist activity. [Sar1,Dtc5]ANG II displayed superior agonist activity, while both [Sar1,Dtc5 and Cle5,Ile8] ANG II displayed superior antagonist activity. In contrast to position 5, Dtc7 substitution for Pro7 of either [Sar1]ANG II or [Sar1,Ile8]ANG II gave analogues with reduced activities. These results are consistent with the hypothesis that conformations of [Sar1]ANG II and [Sar1,Ile8]ANG II containing a C7 conformation in position 7 are preferred for both ANG II agonist and antagonist activity. Incorporation of the L,L-lactam-Phe modification into [Sar1]ANG II gives a pure ANG II antagonist (pA2 8.3), comparable to saralasin (pA2 8.6). In positions 3, 5, and 7 the conformational requirements for the ANG II agonist [Sar1]ANG II and the ANG II antagonist [Sar1,Ile8]ANG II may be different. Individual substitution of (NMe)Ala3, Dtc5, D-Phe8 and Aib8 [[Sar1,Aib8]ANG II: Khosla et al. J. Med. Chem. 1977, 20, 1051-1055] into [Sar1,Ile8]ANG II gives analogues that retain antagonist activity. Multiple substitutions of these types of residues into [Sar1,Ile8]ANG II gives analogue 45 [Sar1,(NMe)Ala3,Dtc5,Aib8]ANG II, 46 [Sar1(NMe)Ala3,D-Phe8]AII, and 47 [Sar1,Dtc5,D-Phe8]AII, which display considerably reduced antagonist activity. In ANG II antagonists the construction of highly constrained analogues may not be possible by the additive substitution of "preferred" constrained amino acids into a single analogue.

The role of position 4 in angiotensin II antagonism: a structure-activity study

A number of [Sar1,(pX)Phe4]-ANG II and [Sar1,(pX)Phe4,Ile8]-ANG II analogues were prepared. A good correlation between pX structure in [Sar1,(pX)Phe4]-ANG II and antagonist activity could not be found. However, the data suggest a general trend: Position 4 para substituents that are hydrophilic and capable of donating a hydrogen atom in a hydrogen bond promote agonist activity, while para substituents that are hydrophobic and incapable of donating a hydrogen atom promote antagonist activity. These properties were found to be optimal in the p-chloro substituent. The resulting analogue [Sar1,(pCl)Phe4]-ANG II is a potent ANG II antagonist in vivo. The pX substituents that promote antagonist activity in the [Sar1,(pX)Phe4]-ANG II series were unfavorable in [Sar1,(pX)Phe4,Ile8]-ANG II analogues. ANG II analogues that are antagonists by virtue of an alteration in position 8 require a position 4 agonist side chain. Concurrent modifications of positions 4 and 8 do not give rise to potent antagonists with reduced partial agonist activity.

Potent angiotensin II antagonists with non-beta-branched amino acids in position 5

Amino acids with lipophilic side chains that contain more than one functional group on the beta-carbon, i.e. a beta-branched hydrocarbon moiety, are required in position 5 of angiotensin II (AII) analogue with potent agonist activity. This requirement for agonist activity does not follow for AII analogues with potent antagonist activity. Straight-chain amino acids may be substituted into position 5 of [Sar1,X5,Ile8]AII with retention or enhancement of antagonist activity, e.g. (X5,pA2 rabbit aorta) Phe, 9.15; Tyr, 9.6; His, 9.0; Glu,9.0; Nle, 8.85, compared to Ile, 9.1. beta-Branched side chains can still enhance the antagonist activities of [Sar1,X5,Ile8]AII analogues, e.g. X5 = (beta Me)Phe, pA2 = 9.3. An X-ray crystal structure of the Boc-(beta Me)Phe DCHA salt, prepared for the synthesis of [Sar1,-(beta Me)Phe5, Ile8]AII, revealed an S,S configuration of alpha- and beta-carbon atoms. Contrary to previous literature reports, chemical nonequivalence of the deta-protons of Pro was observed in the 1H NMR spectra of [Sar1,X5,Ile8]AII analogues bearing both beta-branched X5 side chains (X5 = Ile) and non-beta-branched X5 side chains (X5 = Ala, His).

The importance of residues 2 (arginine) and 6 (histidine) in high-affinity angiotensin II antagonists

The structure-antagonist activity relationship is described for analogues of [Sar1,Ile8]angiotensin II substituted in position 2 (arginine) and position 6 (histidine). An extreme sensitivity of potency to alterations in these positions was observed, suggesting that both residues are important for binding. Evidence is presented suggesting that the position 6 histidine side chain in angiotensin II (AII) is not involved in receptor stimulation. The structure-activity relationship is also explored for both [des-Asp1] AII (AIII) and [des-Asp1,Ile8]AII analogues substituted in position 2 (arginine). The substitution of D-N-methylalanine, D-(NMe)Ala, into position 2 of both [des-Asp1]AII and [des-Asp1,Ile8]AII gives analogues 39 and 40 that appear to be more potent than the native [Arg2]peptides and that are the most potent AIII agonists and antagonists described to date.

Effects of D-amino acid substitution on antagonist activities of angiotensin II analogues

The synthesis and biological activities of angiotensin II (AII) analogues are described and compared to the literature. D-Amino acid substitution was employed to search for novel AII antagonists that would also display reduced partial agonist activity. Substitution of D-amino acids into the interior positions 2-7 of [Sar1,Ile8]-AII gave rise to inactive compounds or weak antagonists. Substitution of D-amino acids into position 8 gave rise to potent antagonists in vivo including [Sar1,D-Phe8]-AII 8, [Sar1,D-(alpha Me)Phe8]-AII (35), [Sar1,D-Trp8]-AII (32), [Sar1,D-Phg8]-AII (29), [Sar1,D-Peg8]-AII (30), and [Sar1,D-Phe8]-AII-NH2 (31). The structural requirements for D-AA8 analogues (antagonists) showed similarities with those of L-AA8 analogues (agonists). The latter three analogues, 29-31, were considerably more potent in vivo than their in vitro affinities would indicate, suggesting that these analogues may resist carboxypeptidase-like degradation. While partial agonist activity was not removed by D-AA8 substitution, [Sar1,D-Phe8]-AII-NH2 (31) displays lower partial agonist activity than [Sar1,Ile8]-AII. A receptor model is presented that highlights the difference between [L-AA8]-AII analogue agonist activity and [D-AA8]-AII analogue antagonist activity.