Pediatric Leukemia Roadmaps Are a Guide for Positive Metastatic Bone Sarcoma Trials.

ALL cures require many MRD therapies. This strategy should drive experiments and trials in metastatic bone sarcomas.

Intraoperative Radiation Therapy for Relapsed or Refractory High-Risk Neuroblastoma: A 27-Year Experience.

PURPOSE: To evaluate outcomes after intraoperative radiation therapy (IORT) in high-risk neuroblastoma (NB), including local control, overall survival, and toxicity. METHODS AND MATERIALS: This was a single institution retrospective study of 92 pediatric patients with NB treated with IORT from 1995 to 2022. Each IORT application was considered a separate event for a total of 110 sites treated. Local failure was calculated using the cumulative incidence function and survival by Kaplan-Meier method from the day of surgery. RESULTS: All patients had high-risk relapsed or treatment refractory disease. Median age was 6 years (range, 2-34 years). Median follow-up for all patients and surviving patients was 16 months and 4 years, respectively. All patients previously received chemotherapy, 93% had prior external beam radiation therapy to the site of IORT (median dose, 21.6 Gy; range, 10-36 Gy), and 94% had a prior surgery for tumor resection. The median IORT dose was 12 Gy (range, 8-18 Gy) and median area treated was 18 cm2 (range, 2.5-60 cm2). The cumulative incidence of local failure was 23% at 2 years and 29% at 5 years. The overall survival (OS) was 44% at 2 years and 29% at 5 years. Local failure after IORT was associated with worse OS (hazard ratio, 1.74; 95% CI, 1.07-2.84; P = .0267). Toxicity from IORT was rare, with postoperative complications likely related to IORT seen in 7 (8%) patients. CONCLUSIONS: Our study represents the largest, most recent analysis of the efficacy and safety of IORT in patients with relapsed or refractory NB. Less than one-third of patients failed locally at 5 years, and achieving local control affected overall survival. Minimal toxicities directly related to IORT were observed. Overall, IORT is an effective and safe technique to achieve local control in high-risk relapsed or refractory neuroblastoma.

Critical elements of pediatric neuroblastoma surgery.

Neuroblastoma (NB) is the most common solid extracranial malignancy of childhood with an incidence of 1 per 100,000 in the United States compromising approximately 10 % of childhood cancer. Unfortunately, patients with high-risk NG continue to have long-term survival less than 50 %. Both Children's Oncology Group and the International Society of Paediatric Oncology have demonstrated the important role of surgery in the treatment of high-risk NB. Herein, we compose the results of an extensive literature review as well as expert opinion from leaders in pediatric surgical oncology, to present the critical elements of effective surgery for high-risk neuroblastoma.

Novel combination of imipridones and histone deacetylase inhibitors demonstrate cytotoxic effect through integrated stress response in pediatric solid tumors.

There is a demonstrated need for new chemotherapy options in pediatric oncology, as pediatric solid tumors continue to plateau at 60% with event-free survival. Imipridones, a novel class of small molecules, represent a potential new therapeutic option, with promising pre-clinical data and emerging clinical trial data in adult malignancies. ONC201, ONC206, and ONC212 are imipridones showing pro-apoptotic anti-cancer response. Using cell viability assays, and protein immunoblotting, we were able to demonstrate single-agent efficacy of all 3 imipridones inducing cell death in pediatric solid tumor cell lines, including osteosarcoma, malignant peripheral nerve sheath tumors, Ewing sarcoma (EWS), and neuroblastoma. ONC201 displayed IC50 values for non-H3K27M-mutated EWS cell lines ranging from 0.86 µM (SK-N-MC) to 2.76 µM (RD-ES), which were comparable to the range of IC50 values for H3K27M-mutated DIPG cells lines (range 1.06 to 1.56 µM). ONC212 demonstrated the highest potency in single-agent cell killing, followed by ONC206, and ONC201. Additionally, pediatric solid tumor cells were treated with single-agent therapy with histone deacetylase inhibitors (HDACi) vorinostat, entinostat, and panobinostat, showing cell killing with all 3 HDACi drugs, with panobinostat showing the greatest potency. We demonstrate that dual-agent therapy with combinations of imipridones and HDACi lead to synergistic cell killing and apoptosis in all pediatric solid tumor cell lines tested, with ONC212 and panobinostat combinations demonstrating maximal potency. The imipridones induced the integrated stress response with ATF4 and TRAIL receptor upregulation, as well as reduced expression of ClpX. Hyperacetylation of H3K27 was associated with synergistic killing of tumor cells following exposure to imipridone plus HDAC inhibitor therapies. Our results introduce a novel class of small molecules to treat pediatric solid tumors in a precision medicine framework. Use of impridones in pediatric oncology is novel and shows promising pre-clinical efficacy in pediatric solid tumors, including in combination with HDAC inhibitors.

Molecular Targets for Novel Therapeutics in Pediatric Fusion-Positive Non-CNS Solid Tumors.

Chromosomal fusions encoding novel molecular drivers have been identified in several solid tumors, and in recent years the identification of such pathogenetic events in tumor specimens has become clinically actionable. Pediatric sarcomas and other rare tumors that occur in children as well as adults are a group of heterogeneous tumors often with driver gene fusions for which some therapeutics have already been developed and approved, and others where there is opportunity for progress and innovation to impact on patient outcomes. We review the chromosomal rearrangements that represent oncogenic events in pediatric solid tumors outside of the central nervous system (CNS), such as Ewing Sarcoma, Rhabdomyosarcoma, Fibrolamellar Hepatocellular Carcinoma, and Renal Cell Carcinoma, among others. Various therapeutics such as CDK4/6, FGFR, ALK, VEGF, EGFR, PDGFR, NTRK, PARP, mTOR, BRAF, IGF1R, HDAC inhibitors are being explored among other novel therapeutic strategies such as ONC201/TIC10.

ONC201 and imipridones: Anti-cancer compounds with clinical efficacy.

ONC201 was originally discovered as TNF-Related Apoptosis Inducing Ligand (TRAIL)-inducing compound TIC10. ONC201 appears to act as a selective antagonist of the G protein coupled receptor (GPCR) dopamine receptor D2 (DRD2), and as an allosteric agonist of mitochondrial protease caseinolytic protease P (ClpP). Downstream of target engagement, ONC201 activates the ATF4/CHOP-mediated integrated stress response leading to TRAIL/Death Receptor 5 (DR5) activation, inhibits oxidative phosphorylation via c-myc, and inactivates Akt/ERK signaling in tumor cells. This typically results in DR5/TRAIL-mediated apoptosis of tumor cells; however, DR5/TRAIL-independent apoptosis, cell cycle arrest, or antiproliferative effects also occur. The effects of ONC201 extend beyond bulk tumor cells to include cancer stem cells, cancer associated fibroblasts and immune cells within the tumor microenvironment that can contribute to its efficacy. ONC201 is orally administered, crosses the intact blood brain barrier, and is under evaluation in clinical trials in patients with advanced solid tumors and hematological malignancies. ONC201 has single agent clinical activity in tumor types that are enriched for DRD2 and/or ClpP expression including specific subtypes of high-grade glioma, endometrial cancer, prostate cancer, mantle cell lymphoma, and adrenal tumors. Synergy with radiation, chemotherapy, targeted therapy and immune-checkpoint agents has been identified in preclinical models and is being evaluated in clinical trials. Structure-activity relationships based on the core pharmacophore of ONC201, termed the imipridone scaffold, revealed novel potent compounds that are being developed. Imipridones represent a novel approach to therapeutically target previously undruggable GPCRs, ClpP, and innate immune pathways in oncology.

Injuries among Amish children: opportunities for prevention.

OBJECTIVES: The purpose of this study was to examine the injury risk patterns among Amish children, many of whom may be exposed to uncommon injuries and limited access to care due to their agrarian lifestyle and remote communities. DESIGN: Retrospective Chart Review. METHODS: With IRB approval, we performed a retrospective review of Amish patients age ≤ 12 years presenting to a level I pediatric trauma center between January 1, 2005, and December 31, 2015. Data abstracted from the institutional trauma registry and electronic medical record were analyzed using descriptive statistics and univariate/multivariate analysis. RESULTS: One hundred eighty-three Amish children were admitted, and 2 died from injuries. Patients were 72.1% male; the median age was 5 (IQR 3-8); median injury severity score (ISS) was 9 (IQR 4-14), Most injuries were the result of blunt force trauma (91.8%). The most frequent mechanisms were falls (42.6%), followed by animal-related (15.3%), and buggy (12.5%). Most injuries occurred at home (44.4%) or on a farm (33.9%). Hay hole falls were a unique source of injury with a high ISS (12; IQR 6-17). The overall median length of stay (LOS) was 2 days (IQR 1-3), with animal-related injuries associated with the longest LOS (3 days; IQR 1-4.75). CONCLUSIONS: The majority of injuries among Amish children are due to falls. Hay hole falls and animal-related injuries result in the highest ISS and longest LOS. These findings identify the farm as a potential target for culturally appropriate interventions for risk modification.

Transcriptomic characterization of fibrolamellar hepatocellular carcinoma.

Fibrolamellar hepatocellular carcinoma (FLHCC) tumors all carry a deletion of ∼ 400 kb in chromosome 19, resulting in a fusion of the genes for the heat shock protein, DNAJ (Hsp40) homolog, subfamily B, member 1, DNAJB1, and the catalytic subunit of protein kinase A, PRKACA. The resulting chimeric transcript produces a fusion protein that retains kinase activity. No other recurrent genomic alterations have been identified. Here we characterize the molecular pathogenesis of FLHCC with transcriptome sequencing (RNA sequencing). Differential expression (tumor vs. adjacent normal tissue) was detected for more than 3,500 genes (log2 fold change ≥ 1, false discovery rate ≤ 0.01), many of which were distinct from those found in hepatocellular carcinoma. Expression of several known oncogenes, such as ErbB2 and Aurora Kinase A, was increased in tumor samples. These and other dysregulated genes may serve as potential targets for therapeutic intervention.

The genomic landscape of fibrolamellar hepatocellular carcinoma: whole genome sequencing of ten patients.

Fibrolamellar hepatocellular carcinoma is a rare, malignant liver tumor that often arises in the otherwise normal liver of adolescents and young adults. Previous studies have focused on biomarkers and comparisons to traditional hepatocellular carcinoma, and have yielded little data on the underlying pathophysiology. We performed whole genome sequencing on paired tumor and normal samples from 10 patients to identify recurrent mutations and structural variations that could predispose to oncogenesis. There are relatively few coding, somatic mutations in this cancer, putting it on the low end of the mutational spectrum. Aside from a previously described heterozygous deletion on chromosome 19 that encodes for a functional, chimeric protein, there were no other recurrent structural variations that contribute to the tumor genotype. The lack of a second-hit mutation in the genomic landscape of fibrolamellar hepatocellular carcinoma makes the DNAJB1-PRKACA fusion protein the best target for diagnostic and therapeutic advancements. The mutations, altered pathways and structural variants that characterized fibrolamellar hepatocellular carcinoma were distinct from those in hepatocellular carcinoma, further defining it as a distinct carcinoma.

Experience with retroperitoneal partial nephrectomy in bilateral Wilms tumor.

INTRODUCTION: Retroperitoneal partial nephrectomy has not been studied as a surgical approach for children with bilateral Wilms tumor. There are advantages to this technique, including isolation of urine leaks to the retroperitoneum, decreased risk of bowel injury, and decreased time to resuming a diet. Presently, all bilateral Wilms tumors are treated with neoadjuvant chemotherapy and attempted nephron-sparing surgery. In this study, we compare the outcomes of the retroperitoneal and transabdominal approaches in doing partial nephrectomy for bilateral Wilms tumor. METHODS: With the institutional review board approval, we reviewed records of 14 pediatric patients with metachronous or synchronous bilateral Wilms tumors who underwent surgery after chemotherapy between 1994 and 2014. Only operative procedures with the intent to cure were included (n=15) and of these, 5 procedures were retroperitoneal and 10 were transabdominal in approach. Individual kidneys operated upon (n=26) were analyzed using the preoperative radius exophytic/endophytic nearness anterior/posterior location nephrometry score to ensure that resected tumors were comparable between the two surgical groups. Charts were retrospectively analyzed for intraoperative parameters and postoperative course. Differences between parameters were evaluated using Mann-Whitney and chi-square tests. RESULTS: Resected tumors in both surgical treatment groups had comparable sizes, nephrometry scores, and rates of anaplasia. Operative time, blood loss, and transfusion requirement were similar between the two groups. The extent of lymph node sampling and rates of R0 resection were equivalent. One adverse intraoperative event, a bowel enterotomy, was seen in the transabdominal group. Patients after retroperitoneal partial nephrectomy required half the time to return to an oral diet as compared with those after a transabdominal surgery, approaching statistical significance (p=0.08). Rates of the postoperative urine leak were similar, though two in the transabdominal group required reoperation for drainage. There were four recurrences, all in the transabdominal group. CONCLUSION: Our experience demonstrates that the retroperitoneal approach is equivalent to the transabdominal technique with regards to intraoperative complications, lymph node dissection, and R0 resection. Advantages include less time to resumption of oral feeding, decreased risk of bowel injury, and isolation of urine leaks to the retroperitoneum. It should be considered a viable surgical option in the treatment of bilateral Wilms tumors.

Endogenous antibodies for tumor detection.

The study of cancer immunology has provided diagnostic and therapeutic instruments through serum autoantibody biomarkers and exogenous monoclonal antibodies. While some endogenous antibodies are found within or surrounding transformed tissue, the extent to which this exists has not been entirely characterized. We find that in transgenic and xenograft mouse models of cancer, endogenous gamma immunoglobulin (IgG) is present at higher concentration in malignantly transformed organs compared to non-transformed organs in the same mouse or organs of cognate wild-type mice. The enrichment of endogenous antibodies within the malignant tissue provides a potential means of identifying and tracking malignant cells in vivo as they mutate and diversify. Exploiting these antibodies for diagnostic and therapeutic purposes is possible through the use of agents that bind endogenous antibodies.

Detection of a recurrent DNAJB1-PRKACA chimeric transcript in fibrolamellar hepatocellular carcinoma.

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare liver tumor affecting adolescents and young adults with no history of primary liver disease or cirrhosis. We identified a chimeric transcript that is expressed in FL-HCC but not in adjacent normal liver and that arises as the result of a ~400-kilobase deletion on chromosome 19. The chimeric RNA is predicted to code for a protein containing the amino-terminal domain of DNAJB1, a homolog of the molecular chaperone DNAJ, fused in frame with PRKACA, the catalytic domain of protein kinase A. Immunoprecipitation and Western blot analyses confirmed that the chimeric protein is expressed in tumor tissue, and a cell culture assay indicated that it retains kinase activity. Evidence supporting the presence of the DNAJB1-PRKACA chimeric transcript in 100% of the FL-HCCs examined (15/15) suggests that this genetic alteration contributes to tumor pathogenesis.

Risk factors and predictors of severity score and complications of pediatric hemorrhagic cystitis.

PURPOSE: We retrospectively analyzed our institutional incidence of hemorrhagic cystitis, identified risk factors, and examined associations of risk factors with disease severity and genitourinary complication rates. MATERIALS AND METHODS: We reviewed charts of all consecutive pediatric patients treated from 1986 to 2010. We analyzed demographics, underlying diagnosis and treatment data to assess risk factors for hemorrhagic cystitis. We also correlated disease severity scores with clinical predisposing factors, and performed univariate and multivariate analyses to examine associations between risk factors and outcomes. RESULTS: Hemorrhagic cystitis was observed in 97 of 6,119 children (1.6%), most of whom (75%) had severity scores of II or III. Mean ± SD age was 12.2 ± 6.3 years for patients with hemorrhagic cystitis and 10.5 ± 7 years for patients without hemorrhagic cystitis (p = 0.017). On univariate analysis increased risk of hemorrhagic cystitis was significantly associated with age greater than 5 years, male gender, cyclophosphamide or busulfan chemotherapy, bone marrow or peripheral blood stem cell transplantation, pelvic radiotherapy and underlying diagnoses of rhabdomyosarcoma, acute leukemia and aplastic anemia. On multivariate analysis age greater than 5 years, allogeneic bone marrow or peripheral blood stem cell transplantation and pelvic radiotherapy were significantly associated with increased risk of hemorrhagic cystitis. Older age, late onset hemorrhagic cystitis, positive urine culture for BK virus and bone marrow or peripheral blood stem cell transplantation were associated with greater disease severity. Patients with higher severity scores more frequently experienced bladder perforation, hydronephrosis, overall hemorrhagic cystitis complications, and increased creatinine and blood urea nitrogen levels during followup. CONCLUSIONS: Older age, previous bone marrow or peripheral blood stem cell transplantation and BK virus in the urine are risk factors for hemorrhagic cystitis and are associated with a higher severity score. Higher severity scores are associated with increased rates of genitourinary complications and renal impairment.

Desmoid fibromatosis in children and adolescents: a conservative approach to management.

PURPOSE: Desmoid fibromatosis is associated with frequent recurrence and significant morbidity, but no metastases. To examine the impact of initial non-operative management on event-free survival (EFS) in children, we reviewed our institutional experience with this tumor. METHODS: We retrospectively reviewed our institutional database for pediatric cases of desmoid fibromatosis treated between 1970 and 2010. Survival was analyzed using the Kaplan-Meier method and log-rank test. RESULTS: Ninety-three patients were identified, with a median follow-up of 6 years. Median age at diagnosis was 16 years. Forty-seven patients presented with primary tumors, and forty-six had recurrent or progressing disease. Five-year OS was 100%, and 5-year EFS was 31.8%, with a median time to event of 1.48 years. There was no significant difference in 5-year EFS between patients who were managed expectantly and those who initially received treatment (21% versus 34%, P=.09). Sex, race, history of trauma, or familial adenomatous polyposis, multifocality, tumor size, tumor location, and resection status did not correlate with EFS. CONCLUSION: Our findings support a conservative initial approach in the management of desmoid fibromatosis. In patients at risk for morbid procedures, upfront resection should be reserved for select tumors that demonstrate aggressive growth or cause serious symptoms.

Malignant liver tumors.

Malignant tumors of the liver comprise a relatively small fraction of the total number of pediatric malignancies. However, these tumors can be a significant cause of morbidity and mortality, and there have been significant therapeutic gains during the past few decades through advances in systemic therapy and surgical treatment. Even in patients with advanced local disease, complete resection is now a possibility because of improvements in liver transplantation techniques. In this review, we will discuss the staging and treatment of common malignant tumors of the liver.

Factors associated with relapse and survival in Wilms tumor: a multivariate analysis.

PURPOSE: Lymph node metastasis and anaplasia predict relapse-free survival in Wilms tumor. We performed a multivariate analysis of our institutional database to identify factors independently associated with relapse-free and overall survival. METHODS: We retrospectively reviewed cases of confirmed Wilms tumor diagnosed between 1990 and 2010 and treated at our institution. The log-rank test was used to screen variables for consideration in the proportional hazards model. RESULTS: A total of 95 patients were treated at our institution during the study period, with a median follow-up of 3.3 years. Factors correlated with overall survival in the univariate analysis were local disease, metastasis, tumor size, anaplasia, renal vein tumor thrombus, inferior vena cava tumor thrombus, lymph node positivity, and tumor rupture. On multivariate analysis, factors associated with increased risk of death were lymph node positivity and anaplasia. Factors correlated with probability of relapse in the univariate analysis were lymph node positivity, anaplasia, and female sex. All 3 of these factors were also independently significant on multivariate analysis. CONCLUSION: Lymph node involvement and anaplasia are significantly correlated with probability of relapse and overall survival, reemphasizing the strong recommendation to sample regional lymph nodes during Wilms tumor resection.

Desmoid tumors in the pediatric population.

Desmoid tumors are benign soft tissue tumors associated with locally aggressive growth and high rates of morbidity, but they do not metastasize via lymphatic or hematogenous routes. While most of the data on desmoid tumors originates in the adult literature, many of the findings have been applied to the management of pediatric patients. This article discusses the epidemiology, etiology, clinical presentation, pathology, and treatment of this rare tumor in the pediatric population and includes a literature review of the most recent large series of pediatric patients with desmoid tumors.

Hodgkin lymphoma presenting with chest wall involvement: a case series.

Chest wall tumors in the pediatric population can have a variety of etiologies, malignancy being the most worrisome. Hodgkin lymphoma (HL) rarely presents as a chest wall mass in the pediatric population. In this report, we describe 3 male pediatric patients, all of whom had chest wall masses present at the initial diagnosis of HL. We also discuss the literature on this topic. We conclude that malignancy and, more specifically, HL should always be considered when evaluating a pediatric patient who presents with a chest wall mass.