Unlocking epigenetics for precision treatment of Ewing's sarcoma.

Ewing's sarcoma (EWS) is a highly aggressive malignant bone tumor primarily affecting adolescents and young adults. Despite the efficacy of chemoradiotherapy in some cases, the cure rate for patients with metastatic and recurrent disease remains low. Therefore, there is an urgent need for innovative therapeutic approaches to address the challenges associated with EWS treatment. Epigenetic regulation, a crucial factor in physiological processes, plays a significant role in controlling cell proliferation, maintaining gene integrity, and regulating transcription. Recent studies highlight the importance of abnormal epigenetic regulation in the initiation and progression of EWS. A comprehensive understanding of the intricate interactions between EWS and aberrant epigenetic regulation is essential for advancing clinical drug development. This review aims to provide a comprehensive overview of both epigenetic targets implicated in EWS, integrating various therapeutic modalities to offer innovative perspectives for the clinical diagnosis and treatment of EWS.

Combinatorial macrophage induced innate immunotherapy against Ewing sarcoma: Turning "Two Keys" simultaneously.

BACKGROUND: Macrophages play important roles in phagocytosing tumor cells. However, tumors escape macrophage phagocytosis in part through the expression of anti-phagocytic signals, most commonly CD47. In Ewing sarcoma (ES), we found that tumor cells utilize dual mechanisms to evade macrophage clearance by simultaneously over-expressing CD47 and down-regulating cell surface calreticulin (csCRT), the pro-phagocytic signal. Here, we investigate the combination of a CD47 blockade (magrolimab, MAG) to inhibit the anti-phagocytic signal and a chemotherapy regimen (doxorubicin, DOX) to enhance the pro-phagocytic signal to induce macrophage phagocytosis of ES cells in vitro and inhibit tumor growth and metastasis in vivo. METHODS: Macrophages were derived from human peripheral blood monocytes by granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF). Flow cytometry- and microscopy-based in-vitro phagocytosis assays were performed to evaluate macrophage phagocytosis of ES cells. Annexin-V assay was performed to evaluate apoptosis. CD47 was knocked out by CRISPR/Cas9 approach. ES cell-based and patient-derived-xenograft (PDX)-based mouse models were utilized to assess the effects of MAG and/or DOX on ES tumor development and animal survival. RNA-Seq combined with CIBERSORTx analysis was utilized to identify changes in tumor cell transcriptome and tumor infiltrating immune cell profiling in MAG and/or DOX treated xenograft tumors. RESULTS: We found that MAG significantly increased macrophage phagocytosis of ES cells in vitro (p < 0.01) and had significant effect on reducing tumor burden (p < 0.01) and increasing survival in NSG mouse model (p < 0.001). The csCRT level on ES cells was significantly enhanced by DOX in a dose- and time-dependent manner (p < 0.01). Importantly, DOX combined with MAG significantly enhanced macrophage phagocytosis of ES cells in vitro (p < 0.01) and significantly decreased tumor burden (p < 0.01) and lung metastasis (p < 0.0001) and extended animal survival in vivo in two different mouse models of ES (p < 0.0001). Furthermore, we identified CD38, CD209, CD163 and CD206 as potential markers for ES-phagocytic macrophages. Moreover, we found increased M2 macrophage infiltration and decreased expression of Cd209 in the tumor microenvironment of MAG and DOX combinatorial therapy treated tumors. CONCLUSIONS: By turning "two keys" simultaneously to reactivate macrophage phagocytic activity, our data demonstrated an effective and highly translatable alternative therapeutic approach utilizing innate (tumor associated macrophages) immunotherapy against high-risk metastatic ES.

High Expression of miR-218-5p in the Peripheral Blood Stream and Tumor Tissues of Pediatric Patients with Sarcomas.

Sarcomas are malignant tumors that may metastasize and the course of the disease is highly aggressive in children and young adults. Because of the rare incidence of sarcomas and the heterogeneity of tumors, there is a need for non-invasive diagnostic and prognostic biomarkers in sarcomas. The aim of the study was to investigate the level of miR-218-5p in peripheral blood and tumor tissue samples of Ewing's sarcoma, osteosarcoma, spindle cell sarcoma patients, and healthy controls, and assessed whether the corresponding molecule was a diagnostic and prognostic biomarker. The study was performed patients (n = 22) diagnosed and treated with Ewing's sarcoma and osteosarcoma and in a control group of 22 healthy children who were matched for age, gender, and ethnicity with the patient group. The expression level of miR-218-5p in RNA samples from peripheral blood and tissue samples were analyzed using the RT-PCR and the expression level of miR-218-5p was evaluated by comparison with the levels in patients and healthy controls. The expression level of miR-218-5p was found to be statistically higher (3.33-fold, p = 0.006) in pediatric patients with sarcomas and when the target genes of miR-218-5p were investigated using the bioinformatics tools, the miR-218-5p was found as an important miRNA in cancer. In this study, the miR-218-5p was shown for the first time to have been highly expressed in the peripheral blood and tumor tissue of sarcoma patients. The results suggest that miR-218-5p can be used as a diagnostic and prognostic biomarker in sarcomas and will be evaluated as an important therapeutic target.

Exploration and optimisation of structure-activity relationships of new triazole-based C-terminal Hsp90 inhibitors towards in vivo anticancer potency.

The development of new anticancer agents is one of the most urgent topics in drug discovery. Inhibition of molecular chaperone Hsp90 stands out as an approach that affects various oncogenic proteins in different types of cancer. These proteins rely on Hsp90 to obtain their functional structure, and thus Hsp90 is indirectly involved in the pathophysiology of cancer. However, the most studied ATP-competitive inhibition of Hsp90 at the N-terminal domain has proven to be largely unsuccessful clinically. Therefore, research has shifted towards Hsp90 C-terminal domain (CTD) inhibitors, which are also the focus of this study. Our recent discovery of compound C has provided us with a starting point for exploring the structure-activity relationship and optimising this new class of triazole-based Hsp90 inhibitors. This investigation has ultimately led to a library of 33 analogues of C that have suitable physicochemical properties and several inhibit the growth of different cancer types in the low micromolar range. Inhibition of Hsp90 was confirmed by biophysical and cellular assays and the binding epitopes of selected inhibitors were studied by STD NMR. Furthermore, the most promising Hsp90 CTD inhibitor 5x was shown to induce apoptosis in breast cancer (MCF-7) and Ewing sarcoma (SK-N-MC) cells while inducing cause cell cycle arrest in MCF-7 cells. In MCF-7 cells, it caused a decrease in the levels of ERα and IGF1R, known Hsp90 client proteins. Finally, 5x was tested in zebrafish larvae xenografted with SK-N-MC tumour cells, where it limited tumour growth with no obvious adverse effects on normal zebrafish development.

Ablation of the dystrophin Dp71f alternative C-terminal variant increases sarcoma tumour cell aggressiveness.

Alterations in Dp71 expression, the most ubiquitous dystrophin isoform, have been associated with patient survival across tumours. Intriguingly, in certain malignancies, Dp71 acts as a tumour suppressor, while manifesting oncogenic properties in others. This diversity could be explained by the expression of two Dp71 splice variants encoding proteins with distinct C-termini, each with specific properties. Expression of these variants has impeded the exploration of their unique roles. Using CRISPR/Cas9, we ablated the Dp71f variant with the alternative C-terminus in a sarcoma cell line not expressing the canonical C-terminal variant, and conducted molecular (RNAseq) and functional characterisation of the knockout cells. Dp71f ablation induced major transcriptomic alterations, particularly affecting the expression of genes involved in calcium signalling and ECM-receptor interaction pathways. The genome-scale metabolic analysis identified significant downregulation of glucose transport via membrane vesicle reaction (GLCter) and downregulated glycolysis/gluconeogenesis pathway. Functionally, these molecular changes corresponded with, increased calcium responses, cell adhesion, proliferation, survival under serum starvation and chemotherapeutic resistance. Knockout cells showed reduced GLUT1 protein expression, survival without attachment and their migration and invasion in vitro and in vivo were unaltered, despite increased matrix metalloproteinases release. Our findings emphasise the importance of alternative splicing of dystrophin transcripts and underscore the role of the Dp71f variant, which appears to govern distinct cellular processes frequently dysregulated in tumour cells. The loss of this regulatory mechanism promotes sarcoma cell survival and treatment resistance. Thus, Dp71f is a target for future investigations exploring the intricate functions of specific DMD transcripts in physiology and across malignancies.

Ewing Sarcoma of the Larynx with Thyroid Cartilage Destruction: A Case Report.

Ewing sarcoma of the larynx is extremely rare, only a few number of cases have been reported. In this report, we describe a case of extraskeletal Ewing sarcoma of the larynx with thyroid cartilage destruction. Laryngoscope, 2024.

Primary Ewing sarcoma of the kidney: a rare entity with diagnostic challenges.

Ewing sarcoma is a very rare tumour with aggressive behaviour and a poor prognosis. It tends to metastasize rapidly. Renal Ewing sarcoma is extremely rare, and only 48 cases have been reported in the literature. Herein, we report the case of a 14-year-old female presenting with a painful left flank swelling. Ultrasound and magnetic resonance imaging showed a large tumour invading the left kidney, heterogeneously enhanced after injection, associated with lymph nodes and peritoneal carcinomatosis. A thoraco-abdomino-pelvic computed tomography scan revealed pulmonary nodules and osteolytic lesions. A biopsy was performed, and histology, immunohistochemistry, and molecular studies confirmed the diagnosis of retroperitoneal Ewing sarcoma. Multi-agent chemotherapy followed by radical nephrectomy was performed, confirming the renal origin, and histology showed a post-therapeutical response. After a 1-year follow-up, there was no evidence of recurrence. We report this case to highlight the rarity of this entity and its challenging clinico-pathological diagnosis when presenting as a renal tumour.

A Report of a Rare Case of BCOR (B-cell Line 6 Corepressor)-Altered Sarcoma of the Lung in a Child.

Ewing sarcoma is one of the small round blue cell tumors of childhood that typically affects bone. Recently, a subgroup of undifferentiated round-cell sarcomas has been genetically identified as BCOR (B-cell Line 6 Corepressor)-altered sarcomas (BAS). We present a case of a six-year-old male child who presented with a chief complaint of shortness of breath and tachypnea and was found to have a large mediastinal mass concerning sarcoma. Preliminary biopsy results were positive for small round blue cells, possibly Ewing sarcoma. After six cycles of chemotherapy, with subsequent shrinkage of mediastinal mass, the patient was able to undergo wedge resection and excision of the mass with en bloc resection of the fifth and sixth rib, preserving his right lung. Final tissue pathology was positive for BAS. There have been only four reported cases of BAS of the chest wall and zero reported cases of primary tumor presentation of the lung, making this a rare presentation of the disease.

Mithramycin and its analogs: Molecular features and antitumor action.

The antitumor antibiotic mithramycin A (MTA) binds to G/C-rich DNA sequences in the presence of dications. MTA inhibits transcription regulated by the Sp1 transcription factor, often enhanced during tumor development. It shows antitumor activity, but its clinical use was discontinued due to toxic side effects. However, recent observations have led to its use being reconsidered. The MTA biosynthetic pathways have been modified to produce mithramycin analogs (mithralogs) that encompass lower toxicity and improved pharmacological activity. Some mithralogs reduce gene expression in human ovarian and prostate tumors, among other types of cancer. They down-regulate gene expression in various cellular processes, including Sp1-responsive genes that control tumor development. Moreover, MTA and several mithralogs, such as EC-8042 (DIG-MSK) and EC-8105, effectively treat Ewing sarcoma by inhibiting transcription controlled by the oncogenic EWS-FLI1 transcription factor.

Diagnosis and management of cancer therapy-related myocarditis in a young female: A case report and review of literature.

BACKGROUND: The treatment of choice for Extra-osseous Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET), a rare neoplasm, is the VAC/IE regimen. This regimen includes Doxorubicin, Vincristine, Cyclophosphamide, Ifosfamide, and Etoposide, all of which have cardiotoxic effects. Myocarditis, a potentially threatening side effect following cancer therapy, can be accurately managed and diagnosed. CASE PRESENTATION: In the current study, we report the case of a 19-year-old female with a mass on the abdominal wall, diagnosed with ES/PNET. She was treated with the VAC/IE regimen. A month after the last session of chemotherapy, she experienced dyspnea. Upon evaluation, a high level of troponin and a low left ventricular ejection fraction (LVEF) were detected via transthoracic echocardiography. She was treated with anti-heart failure drugs, but the response was unsatisfactory. The possibility of Cancer therapy-related myocarditis was suspected, and cardiac magnetic resonance imaging (CMR) confirmed acute myocarditis. This patient exhibited a significant response to intravenous immunoglobulin (IVIG), with her LVEF improving from 30-35% to 50% within three months. CONCLUSION: In this case, based on negative tests and the absence of viral signs and symptoms, Cancer therapy-related myocarditis is highly suspected as the cause of myocarditis. This case underscores the importance of accurately utilizing CMR as a non-invasive method for diagnosing myocarditis. It effectively highlights the identification of reversible myocarditis with appropriate treatment and the notable response to IVIG, suggesting its potential as a favorable treatment for myocarditis in younger patients.

Effectiveness and safety of primary prophylaxis with G-CSF for patients with Ewing sarcomas: a systematic review for the Clinical Practice Guidelines for the Use of G-CSF 2022 of the Japan Society of Clinical Oncology.

BACKGROUND: Multidrug chemotherapy for Ewing sarcoma can lead to severe myelosuppression. We proposed two clinical questions (CQ): CQ #1, "Does primary prophylaxis with G-CSF benefit chemotherapy for Ewing sarcoma?" and CQ #2, "Does G-CSF-based intensified chemotherapy improve Ewing sarcoma treatment outcomes?". METHODS: A comprehensive literature search was conducted in PubMed, Cochrane Library, and Ichushi web databases, including English and Japanese articles published from 1990 to 2019. Two reviewers assessed the extracted papers and analyzed overall survival (OS), febrile neutropenia (FN) incidence, infection-related mortality, quality of life (QOL), and pain. RESULTS: Twenty-five English and five Japanese articles were identified for CQ #1. After screening, a cohort study of vincristine, ifosfamide, doxorubicin, and etoposide chemotherapy with 851 patients was selected. Incidence of FN was 60.8% with G-CSF and 65.8% without; statistical tests were not conducted. Data on OS, infection-related mortality, QOL, or pain was unavailable. Consequently, CQ #1 was redefined as a future research question. As for CQ #2, we found two English and five Japanese papers, of which one high-quality randomized controlled trial on G-CSF use in intensified chemotherapy was included. This trial showed trends toward lower mortality and a significant increase in event-free survival for 2-week interval regimen with the G-CSF primary prophylactic use compared with 3-week interval. CONCLUSION: This review indicated that G-CSF's efficacy as primary prophylaxis in Ewing sarcoma, except in children, is uncertain despite its common use. This review tentatively endorses intensified chemotherapy with G-CSF primary prophylaxis for Ewing sarcoma.

Proximal femur alloprosthesis in a pediatric patient with Ewing sarcoma: Case report.

INTRODUCTION AND IMPORTANCE: Ewing sarcoma is a primary malignant tumor of bone and, to a lesser extent, soft tissues. Within oncological management, surgery with extensive local control and reconstruction is the most accepted option, however, the size, extension of the tumor, the age of the patient and distant involvement can make this option difficult. CASE PRESENTATION: We present a clinical case of a 3-year-old infant with Ewing sarcoma in the proximal femur, who was managed with wide resection of the tumor plus proximal humerus allograft, which acted as a proximal femur for 2 years and then presented joint failure due to what was done was the application of a cemented stem over the remnant of the allograft to save the hip. CLINICAL DISCUSSION: In the presented case, similar to the report by Zoccali a malignant tumor in the proximal femur of a pediatric patient is documented. In these cases, where the distal femoral growth plate is disease-free, a reconstruction technique preserving the growth plate is proposed. CONCLUSION: The technique of proximal femoral allograft with a proximal humeral graft is an acceptable reconstructive treatment alternative for young patients with Ewing sarcoma, especially when conventional treatment options are limited. This approach helps avoid limb-threatening surgeries such as amputation or rotationplasty, providing a viable and functional solution for limb salvage in these cases.

Cold Physical Plasma Reduces Motility of Various Bone Sarcoma Cells While Remodeling the Cytoskeleton.

BACKGROUND/AIM: Cold physical plasma (CPP) has emerged as an effective therapy in oncology by inducing cytotoxic effects in various cancer cells, including chondrosarcoma (CS), Ewing's sarcoma (ES), and osteosarcoma (OS). The current study investigated the impact of CPP on cell motility in CS (CAL-78), ES (A673), and OS (U2-OS) cell lines, focusing on the actin cytoskeleton. MATERIALS AND METHODS: The CASY Cell Counter and Analyzer was used to study cell proliferation and determine the optimal concentrations of fetal calf serum to maintain viability without stimulation of cell proliferation. CellTiter-BlueCell viability assay was used to determine the effects of CPP on the viability of bone sarcoma cells. The Radius assay was used to determine cell migration. Staining for Deoxyribonuclease I, G-actin, and F-actin was used to assay for the effects on the cytoskeleton. RESULTS: Reductions in cell viability and motility were observed across all cell lines following CPP treatment. CPP induced changes in the actin cytoskeleton, leading to decreased cell motility. CONCLUSION: CPP effectively reduces the motility of bone sarcoma cells by altering the actin cytoskeleton. These findings underscore CPP's potential as a therapeutic tool for bone sarcomas and highlight the need for further research in this area.

Superficial Neurocristic EWSR1::FLI1 Fusion Tumor: A Distinctive, Clinically Indolent, S100 Protein/SOX10-Positive Neoplasm.

It is now understood that identical gene fusions may be shared by different entities. We report a distinctive neoplasm of the skin and subcutis, harboring the Ewing sarcoma-associated EWSR1::FLI1 fusion but differing otherwise from Ewing sarcoma. Slides and blocks for 5 cutaneous neoplasms coded as other than Ewing sarcoma and harboring EWSR1::FLI1 were retrieved. Immunohistochemical and molecular genetic results were abstracted from reports. Methylation profiling was performed. Clinical information was obtained. The tumors occurred in 4 men and 1 woman (median: 25 years of age; range: 19-69 years) and involved the skin/subcutis of the back (2), thigh, buttock, and chest wall (median: 2.4 cm; range: 1-11 cm). Two tumors were present "years" before coming to clinical attention. The lesions were multinodular and circumscribed and consisted of nests of bland, round cells admixed with hyalinized collagenous bands containing spindled cells. Hemorrhage and cystic change were often present; necrosis was absent. All were diffusely S100 protein/SOX10-positive; 4 of 5 were CD99-negative. One tested case was strongly positive for NKX2.2. A variety of other tested markers were either focally positive (glial fibrillary acidic protein, p63) or negative. Molecular genetic results were as follows: EWSR1 exon 7::FLI1 exon 8, EWSR1 exon 11::FLI1 exon 5, EWSR1 exon 11::FLI1 exon 6, EWSR1 exon 7::FLI1 exon 6, and EWSR1 exon 10::FLI1 exon 6. Methylation profiling (3 cases) showed these to form a unique cluster, distinct from Ewing sarcoma. All patients underwent excision with negative margins; one received 1 cycle of chemotherapy. Clinical follow-up showed all patients to be alive without disease (median: 17 months; range: 11-62 months). Despite similar gene fusions, the morphologic, immunohistochemical, epigenetic, and clinical features of these unique EWSR1::FLI1-fused neoplasms of the skin and subcutis differ substantially from Ewing sarcoma. Interestingly, EWSR1 rearrangements involved exons 10 or 11, only rarely seen in Ewing sarcoma, in a majority of cases. Superficial neurocristic EWSR1::FLI1 fusion tumors should be rigorously distinguished from true cutaneous Ewing sarcomas.

Primary Chest Wall Ewing Sarcoma: Treatment and Long-Term Results.

OBJECTIVE: The aim of the study is to evaluate early and long-term results of chest wall primary Ewing's sarcoma patients treated in the time period February 2000-February 2023 by a multidisciplinary approach. METHODS: We retrospectively reviewed the medical records of patients who underwent chest wall resection for a primary tumor. Treatment approach, extent of resection, 30-day mortality, overall survival (OS), local recurrence-free survival (LRFS), and metastasis-free survival (MFS) were analyzed. RESULTS: Overall, n = 15 consecutive patients were treated for chest wall primary Ewing's sarcoma. A median of n = 3 ribs was resected with a median of n = 2 ribs adjacent to the lesion. Resections were extended to the adjacent structures in n = 5 patients (33.3%). In all cases, we performed a prosthetic reconstruction, associated with muscle flap (n = 10, 66.6%) or with rigid titanium bars and muscle flap (n = 6, 40%). A radical resection was accomplished in n = 13 patients (84.6%). The median surgical time was 310 ± 120 min; median hospitalization was 7.8 ± 1.9 days. Post-operative mortality was zero. We recorded n = 4 (30.7%) post-operative complication. The median follow-up (FU) was 26 months. Moreover, 5-year overall and event-free survival were 52% and 48%, respectively. CONCLUSIONS: This case series confirms the benefit of the multidisciplinary approach for Ewing sarcomas in early and long-term results.

[Ewing sarcoma/primitive hepatic neuroectodermal tumor]. / Sarcoma de Ewing/tumor neuroectodérmico primitivo hepático.

Ewing sarcoma (ES) and primitive neuroectodermal tumor (PNET) belong to the group of neoplasms called small round cell tumors. PNETs have been divided into central and peripheral. ES and peripheral PNETs arise from bones, soft tissues, or peripheral nerves. We present a case of hepatic ES/PNET in a healthy man that began four months before consultation with abdominal symptoms and weight loss. Upper gastrointestinal endoscopy and laboratory tests revealed no notable findings. The abdominal tomography revealed an enlarged liver due to a solid lesion that involved all its segments with intravenous contrast enhancement and large areas of necrosis. It compressed and displaced neighboring structures. Core needle biopsy of the liver lesion was performed: small round cell neoplasm. Immunohistochemistry revealed negativity for CD45, CKA1/A3, chromogranin, synaptophysin, and cytokeratins CK7 and CK20. Dim CD56 expression and CD99, FLI-1, and NKX2 positivity. He underwent chemotherapy treatment with carboplatin and etoposide for 6 cycles with clinical improvement and tolerance. Control images showed reduction of the mass with involvement of the right hepatic lobe, involvement of the inferior vena cava, infiltration of the right adrenal gland and upper pole of the right kidney. He was referred to hepatobiliary surgery for surgical resection of the residual lesion. The patient rejected the proposed surgical procedure. Our objective is to highlight the clinical and histological diagnostic challenge of this entity that requires ruling out other clinical entities.

El sarcoma de Ewing (ES) y el tumor neuroectodérmico primitivo (PNET) pertenecen al grupo de neoplasias denominadas tumores de células pequeñas y redondas. Los PNET se dividen en centrales y periféricos. El ES y los PNET periféricos surgen del tejido óseo, de los tejidos blandos o nervios periféricos. Presentamos un caso de ES/PNET hepático en un hombre sano que inició cuatro meses antes de la consulta con síntomas abdominales y pérdida de peso. La endoscopia digestiva alta y la analítica no revelaron hallazgos relevantes. En la tomografía de abdomen se evidenció hígado aumentado de tamaño a expensas de lesión sólida que comprometía todos sus segmentos con realce al contraste endovenoso y grandes áreas de necrosis. Comprimía y desplazaba estructuras vecinas. Se realizó biopsia con aguja gruesa de la lesión hepática: neoplasia de células pequeñas y redondas. La inmunohistoquímica reveló negatividad para CD45, CKA1/A3, cromogranina, sinaptofisina y citoqueratinas CK7 y CK20. Expresión tenue de CD56 y positividad de CD99, FLI-1 y NKX2. Realizó tratamiento quimioterápico con carboplatino y etopósido por 6 ciclos con mejoría clínica y tolerancia al mismo. En imágenes de control se evidenció reducción de la masa con afección del lóbulo hepático derecho, compromiso de la vena cava inferior, infiltración de la glándula suprarrenal y polo superior del riñón derechos. Se remitió a cirugía hepatobiliar para resección quirúrgica de la lesión residual. El paciente rechazó el procedimiento quirúrgico. Nuestro objetivo es destacar el desafío diagnóstico clínico e histológico de esta entidad que obliga a descartar otras entidades clínicas.

Ewing sarcoma of the pancreas: a pediatric case report and narrative literature review.

Ewing's Sarcoma (ES) is an rare, small round-cell sarcoma that predominantly occurs in children and young adults, with both skeletal and extraskeletal manifestations. However, pancreatic ES, due to its rarity, is infrequently featured in scholarly literature, with only a scant 43 reported instances. Our study describes a case of pancreatic ES in an 8-year-old boy who was found to have an abdominal mass. Following an exhaustive examination, the boy was diagnosed with a neoplasm in the pancreatic head and underwent a complex surgical procedure encompassing pancreatoduodenectomy and partial transverse colectomy. Immunohistochemical assays confirmed the neoplastic cells' positivity for Cluster of Differentiation 99(CD99), Vimentin, and NK2 Homeobox 2(NKX2.2), while genomic testing identified an EWSR1-FLI1(Ewing Sarcoma Breakpoint Region 1-Friend Leukemia Integration 1) gene fusion. This led to a conclusive diagnosis of pancreatic Ewing's Sarcoma. The patient underwent seven cycles of adjuvant chemotherapy, alternating between VDC (Vincristine, Doxorubicin, Cyclophosphamide) and IE (Ifosfamide, Etoposide) tri-weekly, but did not undergo radiotherapy. At present, the patient remains neoplasm-free. Through our case analysis and comprehensive review of the existing literature, we aim to underscore th rarity of pancreatic Ewing's sarcoma and to highlight the efficacy of our individualized therapeutic approach.

Autonomic responses in young females with typical vasovagal syncope.

To determine whether young women who have experienced typical vasovagal syncope (tVVS) have altered autonomic response parameters, based on a battery of autonomic tests and maneuvers. Notably, previous studies including small cohorts and a partial list of tests yielded conflicting results. A total of 91 otherwise healthy women were included and divided according to those who had experienced tVVS (39 patients) or not (52 patients). Heart rate variability was evaluated at rest, under strict conditions, during 5 min of standing and during a deep breathing test. Response to Valsalva maneuver and Ewing maneuver were also quantified and compared. Both groups had similar clinical characteristics at baseline. No significant differences were found between the two groups in any of the autonomic parameters evaluated. Autonomic responses in young women who experienced typical vasovagal syncope at baseline were indistinguishable from those who did not. Thus, using non-tilt test autonomic screening tests does not seem to provide diagnostic benefits, and may not be useful in predicting recurrence in this patient population.

Differential cyclin-E1 expression in CIC-rearranged sarcoma.

CIC-rearranged sarcoma (CRS) is a group of high-grade undifferentiated small round cell sarcomas examined as a separate entity in the current WHO classification; since it shows more aggressive clinical behavior and distinct morphological and molecular features compared to Ewing sarcoma (ES). As CCNE1 expression is associated with tumor growth in CIC::DUX4 sarcomas, we aimed to demonstrate the value of cyclin E1 expression in CRS. Cyclin E1 immunohistochemistry and break-apart FISH for EWSR1 and CIC gene rearrangements were performed on 3-mm tissue microarrays composed of 40 small round cell tumors. Five cases were classified as CRS, whereas 22 were ES and 13 were unclassified (EWSR1-/CIC-). Among all three diagnostic groups, we found cyclin E1 expression level to be higher in CRS (80 %) and unclassified groups (61.5 %) compared to ES (4.5 %, p < 0.001). In addition, high cyclin E1 expression levels were associated with higher mean age at diagnosis, presence of atypical histology and myxoid stroma, low CD99 expression, and presence of metastasis at diagnosis. The sensitivity and specificity of high cyclin E1 expression in detecting non-ES cases were 95.5 % and 66.7 %, respectively. However, the correlation between cyclin E1 expression level and survival was not statistically significant. This is the first study that shows cyclin E1 immunohistochemical expression in EWSR1-negative undifferentiated small cell sarcomas, particularly CRS.

Therapeutic Targeting of DNA Repair Pathways in Pediatric Extracranial Solid Tumors: Current State and Implications for Immunotherapy.

DNA damage is fundamental to tumorigenesis, and the inability to repair DNA damage is a hallmark of many human cancers. DNA is repaired via the DNA damage repair (DDR) apparatus, which includes five major pathways. DDR deficiencies in cancers give rise to potential therapeutic targets, as cancers harboring DDR deficiencies become increasingly dependent on alternative DDR pathways for survival. In this review, we summarize the DDR apparatus, and examine the current state of research efforts focused on identifying vulnerabilities in DDR pathways that can be therapeutically exploited in pediatric extracranial solid tumors. We assess the potential for synergistic combinations of different DDR inhibitors as well as combinations of DDR inhibitors with chemotherapy. Lastly, we discuss the immunomodulatory implications of targeting DDR pathways and the potential for using DDR inhibitors to enhance tumor immunogenicity, with the goal of improving the response to immune checkpoint blockade in pediatric solid tumors. We review the ongoing and future research into DDR in pediatric tumors and the subsequent pediatric clinical trials that will be critical to further elucidate the efficacy of the approaches targeting DDR.