Ewing's Family Research Articles

Management of Ewing Family of Tumors Arising from Chest Wall in Children

Management of Ewing Family of Tumors Arising from Chest Wall in Children

Insights into Molecular Diversity within the FUS/EWS/TAF15 Protein Family: Unraveling Phase Separation of the N-Terminal Low-Complexity Domain from RNA-Binding Protein EWS.

The FET protein family, comprising FUS, EWS, and TAF15, plays crucial roles in mRNA maturation, transcriptional regulation, and DNA damage response. Clinically, they are linked to Ewing family tumors and neurodegenerative diseases such as amyotrophic lateral sclerosis. The fusion protein EWS::FLI1, the causative mutation of Ewing sarcoma, arises from a genomic translocation that fuses a portion of the low-complexity domain (LCD) of EWS (EWSLCD) with the DNA binding domain of the ETS transcription factor FLI1. This fusion protein modifies transcriptional programs and disrupts native EWS functions, such as splicing. The exact role of the intrinsically disordered EWSLCD remains a topic of active investigation, but its ability to phase separate and form biomolecular condensates is believed to be central to EWS::FLI1's oncogenic properties. Here, we used paramagnetic relaxation enhancement NMR, microscopy, and all-atom molecular dynamics (MD) simulations to better understand the self-association and phase separation tendencies of the EWSLCD. Our NMR data and mutational analysis suggest that a higher density and proximity of tyrosine residues amplify the likelihood of condensate formation. MD simulations revealed that the tyrosine-rich termini exhibit compact conformations with unique contact networks and provided critical input on the relationship between contacts formed within a single molecule (intramolecular) and inside the condensed phase (intermolecular). These findings enhance our understanding of FET proteins' condensate-forming capabilities and underline differences between EWS, FUS, and TAF15.

Association of chemotherapy dose intensity and age with outcomes in patients with Ewing's family sarcoma.

Ewing's family sarcoma (EFS) is an aggressive malignancy with a peak incidence in adolescents. Multimodal treatment involves surgery and/or radiotherapy, and chemotherapy typically with VDC/IE (vincristine, doxorubicin, and cyclophosphamide alternating with ifosfamide and etoposide). There is a paucity of data for the treatment of adults, with protocols extrapolated from the pediatric setting. This study aimed to assess patterns of care, chemotherapy tolerability across age groups, and outcomes from four Australian sarcoma centers. ANZSA ACCORD sarcoma database and medical records were used to identify and collect data of patients aged≥10 years with EFS who received VDC/IE between 2010 and 2020. Survival outcomes were analyzed based on chemotherapy received dose intensity (RDI). Clinical predictors of RDI were explored using logistic regression. Of 146 patients with EFS, 76 received VDC/IE. The majority had localized disease (65%). Seventy-one percent completed scheduled chemotherapy, with some requiring dose reduction (29%), delay>7 days (65%), or cycle omission (4%). Hematological toxicity was the main reason for dose reduction/delay. Fifty-seven percent patients achieved an acceptable RDI ≥85%. Compared to those aged 10-19, the odds ratio for acceptable RDI aged 40-59 was 0.20 (95% CI 0.04-0.86, p=0.04). RDI was an independent prognostic factor for overall survival, after accounting for age, gender, Ewing's type, primary site, and stage (adjusted HR 0.25 [95% CI 0.10-0.63], p=0.004). Survival outcomes in EFS were associated with chemotherapy RDI. Older adults more commonly required dose reduction or early cessation of treatment due to toxicity. VDC/IE chemotherapy should be carefully tailored in adults>40 years.

Adamantinoma-like Ewing Sarcoma (ALES) May Harbor FUS Rearrangements : A Potential Diagnostic Pitfall.

Adamantinoma-like Ewing sarcoma (ALES) is a rare malignancy currently considered a variant of Ewing sarcoma with most known cases harboring EWSR1 rearrangements. Herein we present a series of 6 cases of EWSR1 -negative ALES. The tumors arose in the sinonasal tract (n=3), major salivary glands (submandibular gland=1; parotid=1), and anterior mediastinum (n=1) in patients ranging from 25 to 79 years of age. Most tumors were basaloid in appearance, growing in large nests separated by interlobular fibrosis without overt squamous pearls. However, 1 case closely resembled a well-differentiated neuroendocrine tumor with uniformly round nuclei, eosinophilic cytoplasm, and trabecular architecture. All cases were diffusely positive for pan-cytokeratin, p40 or p63, and CD99. A subset of cases showed diffuse reactivity for synaptophysin, including 1 sinonasal tumor which also demonstrated sustentacular S100 protein expression. Molecular testing showed FUS rearrangements in all cases. Gene partners included known ETS family members FEV (n=2) and FLI1 (n=1). Our results expand the molecular diagnostic considerations for ALES to include FUS rearrangements. We also show that ALES may harbor FUS :: FLI1 fusion, which has not been previously reported in the Ewing family of tumors. Furthermore, ALES may show unusual histologic and immunophenotypic features that can overlap with olfactory carcinoma including S100-positive sustentacular cells. ALES should be considered in the diagnostic differential of small round cell tumors and tumors with neuroendocrine differentiation with immunohistochemical workup to include p40 and CD99/NKX2.2.

Replication Timing Aberration of KIF14 and MDM4 / PI3KC 2 β Alleles and Aneuploidy as Markers of Chromosomal Instability and Poor Treatment Response in Ewing Family Tumor Patients.

Replication timing of allelic gene pairs is strictly regulated according to expression, genome stability, and epigenetic changes, and tumorigenesis may be associated with changes in the allelic replication in various tumors. Our aim was to determine whether such alterations had a prognostic value in Ewing's family tumor (EFT) patients. The KIF14 and MDM4 / PI3KC 2β and the centromeric satellite sequence of chromosomes 8 and 12 were used for replication timing assessments. Aneuploidy was assessed by enumerating the copy numbers of chromosomes 8 and 12. Replication timing and aneuploidy were detected cytogenetically using multicolors fluorescence in situ hybridization assay applied in 135 EFT. Patients with trisomy 8 presented an association with an asynchronous replication pattern (SD) of MDM4 / PI3KC 2β genes ( p = 0.013). Trisomy 12 was associated with a synchronous pattern (DD) of KIF14 probe signals ( p = 0.04). The DD synchronous replication pattern of KIF14 showed a correlation with age ( p < 0.0001), and the SS synchronous replication pattern of the same locus showed a correlation with lung metastatic ( p = 0.012). The subgroup of patients presenting with multiplet signals of MDM4 / PI3KC 2β showed an association with treatment response ( p = 0.045) and age ( p = 0.033). Replication pattern of KIF14 may, significantly, be associated with chromosomal instability as MDM4 / PI3KC 2β may be a considerably new marker of poor treatment response in EFT patients.

Routine EWS Fusion Analysis in the Oncology Clinic to Identify Cancer-Specific Peptide Sequence Patterns That Span Breakpoints in Ewing Sarcoma and DSRCT.

(1) Background: EWS fusion genes are associated with Ewing sarcoma and other Ewing family tumors including desmoplastic small round tumor, DSRCT. We utilize a clinical genomics workflow to reveal real-world frequencies of EWS fusion events, cataloging events that are similar, or divergent at the EWS breakpoint. (2) Methods: EWS fusion events from our next-generation sequencing panel (NGS) samples were first sorted by breakpoint or fusion junctions to map out the frequency of breakpoints. Fusion results were illustrated as in-frame fusion peptides involving EWS and a partner gene. (3) Results: From 2471 patient pool samples for fusion analysis at the Cleveland Clinic Molecular Pathology Laboratory, we identified 182 fusion samples evolved with the EWS gene. They are clustered in several breakpoints: chr22:29683123 (65.9%), and chr22:29688595 (2.7%). About 3/4 of Ewing sarcoma and DSRCT tumors have an identical EWS breakpoint motif at Exon 7 (SQQSSSYGQQ-) fused to a specific part of FLI1 (NPSYDSVRRG or-SSLLAYNTSS), ERG (NLPYEPPRRS), FEV (NPVGDGLFKD) or WT1 (SEKPYQCDFK). Our method also worked with Caris transcriptome data, too. Our primary clinical utility is to use this information to identify neoantigens for therapeutic purposes. (4) Conclusions and future perspectives: our method allows interpretation of what peptides result from the in-frame translation of EWS fusion junctions. These sequences, coupled with HLA-peptide binding data, are used to identify potential sequences of cancer-specific immunogenic peptides for Ewing sarcoma or DSRCT patients. This information may also be useful for immune monitoring (e.g., circulating T-cells with fusion-peptide specificity) to detect vaccine candidates, responses, or residual disease.

PAINLESS UNILATERAL PROPTOSIS PRESENTING AS EWING'S SARCOMA- A RARE CASE REPORT

Ewing's sarcoma is a part of a spectrum of the Ewing family of soft tissue tumors that have a primitive neuro-ectodermal origin most commonly originating from the appendicular and axial skeleton. Occurrence in the orbit is a rare presentation. case report a 15-year-old girl presented with painless unilateral swelling of the right eye since 4 months on histopathological examination came out to be a small round cell tumor with primitive neuroendocrine origin. she was started on chemotherapy with VAC+IE regimen as induction chemotherapy but as the disease was progressive and not responding after 17 cycles of alternating VAC+IE second-line chemotherapy with irinotecan and temozolomide was started and after three cycles surgery was deferred i/v/o intracranial extension so she was treated with external beam radiotherapy 59.4gy in 33#'s at 1.8gy/# with concurrent irinotecan and temozolomide with complete response after radiotherapy. she was on follow-up for 4 months and was later diagnosed with secondary deposits in the lung which she could not cave in and expired.

Rare site and age of presentation: Prostatic sarcoma of the Ewing family in an adolescent

Ewing sarcoma/primitive neuroectodermal tumor (PNET) is the second most primary malignant bone tumor in children and adolescents between 10 and 25 years. The extraosseous sarcomas are rare and often cause diagnostic confusion for clinicians. The cell of origin is unclear, but exhibits rapid growth and recurrence, leading to a poor survival rate of 10% only. This imposes an increased risk of chronic health conditions, financial burden, and impaired quality of life. We report the uncommon presentation in age and site of the tumor in the peri-prostatic tissue of a 14-year-old boy and discuss our treatment approach. An exploratory observational case study was conducted. The ultrasound of an enlarged pelvis mass showed a large heterogeneously hyperechoic lesion with central necrosis and increased vascularity in the mass. The magnetic resonance imaging scan and histopathology of the transrectal ultrasound-guided biopsy specimen confirmed the prostate tumor. The transrectal biopsy proved to be a feasible and effective diagnostic tool for such an unclear pelvic mass. The extraskeletal manifestation of Ewing’s sarcoma imposes diagnostic confusion, but the case fulfilled the extraosseous Ewing sarcoma’s diagnostic characteristic. The Ewing’s sarcoma/PNET of the prostate being rare and posing a poor prognosis needs vigilant differential diagnosis and a multidisciplinary treatment approach for optimal and cost-effective treatments.

Adamantinoma like Ewing Family Tumor of the Eighth Rib, A Rare Case Report and Review of Literature

Ewing sarcoma is a rare malignant tumor of bone and soft tissue that occurs primarily in children and young adults. It belongs to the Ewing family of tumors that are characterized by uniform small blue.

Abstract 1086: PEGylated talazoparib enhances therapeutic window of its combination with temozolomide in Ewing sarcoma

Abstract Introduction: The Ewing family of sarcomas is the fourth most common highly malignant childhood cancer. Current standard therapy is relatively ineffective for relapsed and metastatic Ewing sarcoma predominantly due to development of resistance to chemotherapeutics. Nanoparticle-formulated drugs are reported to increase uptake into tumor tissue, while reducing drug access to normal tissues, because of reduced permeability of normal vasculature. This potentially leads to lower dose exposure in normal tissues and reduced toxicity. The purpose of this study was to evaluate the antitumor activity of the PEGylated poly(ADP) ribose polymerase 1/2 (PARP1/2) inhibitor talazoparib combined with the DNA alkylating agent temozolomide (TMZ) in Ewing sarcoma xenograft models and other pediatric cancers. Method:. We evaluated the preclinical efficacy of PEGylated talazoparib (PEG~TLZ), alone or in combination with TMZ, in Ewing sarcoma and glioblastoma patient derived xenograft (PDX) models. Additional solid tumor models, such as rhabdomyosarcoma, Wilms tumor, malignant rhabdoid tumor, osteosarcoma, and synovial sarcoma were evaluated using a novel single mouse testing approach. PEG~TLZ was administered as a single administration intraperitoneally to mice bearing subcutaneous tumors at a single dose of 5 - 20 µmol/kg alone, or at 10 µmol/kg on day 1 combined with TMZ administered orally at 40 mg/kg starting on day 3 or 4 for 5 consecutive days. Results: Mice bearing Ewing sarcoma and MGMT-deficient glioblastoma xenografts tolerated PEG~TLZ+TMZ with minimal toxicity and achieved maintained complete response (MCR). The time-separated drug administration schedule of the single dose of PEG~TLZ followed by the 5-day TMZ treatment demonstrated objective responses in Ewing sarcoma, rhabdoid tumor, rhabdomyosarcoma, and glioblastoma PDX models. Conclusion: We evaluated the range of PEG~TLZ+TMZ activity among pediatric solid tumor panels using conventional and single-mouse testing approaches, and demonstrated that PEG~TLZ combined with delayed TMZ administration enhances the therapeutic window of the treatment compared to free TLZ. From the clinical standpoint, the single intravenous administration of PEG~TLZ could be advantageous for treating infants and young children. Citation Format: Vanessa Del Pozo, Andrew J. Robles, Shaun Fontaine, Qianqian Liu, Joel E. Michalek, Peter J. Houghton, Raushan Kurmasheva. PEGylated talazoparib enhances therapeutic window of its combination with temozolomide in Ewing sarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1086.

Nested set information derived from fusion genes in Ewing sarcoma and other cancers.

e23521 Background: Ewing family tumors including Ewing sarcoma (ES) and desmoplastic small round cell tumor (DSRCT) are characterized by EWSR1 and ETS fusion partners including EWS-FLI1, EWS-ERG, EWS-WT1, and others. Since 2019 our Next Generation Sequencing (NGS) sarcoma panel (N = 338) identified both fusion partners and exons containing the EWS breakpoint in ES and DSRCT. Hence, it should be possible to learn more about the exact breakpoints of EWS fusion genes. The molecular diversity and functionality of these fusion transcripts, especially the exact sequence, which could be identical, similar, or unique, may have significant biological implications for diagnostics and treatment options. We have used in-frame analysis of EWS gene fusion breakpoints to identify corresponding polypeptides spanning the breakpoints of the most common EWS gene fusions to provide useful insights about ES and DSRCT. Methods: Pathology reports and EWS gene fusions were analyzed using the Cleveland Clinic NGS panel which is based on anchored multiplex polymerase chain reaction (PCR) enriched for 34 gene targets. The amplicons were subjected to massively parallel sequencing with 151x2 cycle pair-end reads. An informatics pipeline was used for read alignment (GRCh37 as reference genome), fusion identification, and annotation. The DNA sequence across fusion junction and translational amino acid sequences were extracted for comparison in a preliminary teaching set (37/338 EWS fusions). Results: EWS-FLI1 fusions at exon 7-7 (chr22:29683123-chr11:128675261) and exon 7-6 (chr22:29683123-chr11:128651853) were the most common fusion genes in ES (N = 24/32;75%). Other ES gene fusions included exons 10-6, 7-10, 9-8, 7-2 EWS-FEV, 7-8 EWS-ERG, 7-9 EWS-ERG, and 10-9 EWS-ERG. EWS-WT1 gene fusions (chr22:29683123-chr11:32414301) in DSRCT exon 7-7 occurred in 4 of 5 cases (80%). In frame analysis of the common gene fusions in 75% of ES and DSRCT (total n = 37) yielded identical corresponding polypeptides that span the breakpoint (table). Conclusions: Analysis of ES and DSRCT fusion genes provides evidence that cancer-specific fusion genes are associated with common identical breakpoints and corresponding in-frame polypeptides. Our results show that the identification of in-frame polypeptides from the fusion gene sequencing can identify potential nested sets of cancer-specific mRNAs and polypeptides. This information may become relevant for diagnostic and therapeutic targets future vaccines and diagnostics against ES and DSRCT as well as other cancers characterized by fusion genes or frameshift mutations. [Table: see text]

Comorbidities rather than older age define outcome in adult patients with tumors of the Ewing sarcoma family.

BackgroundEwing family of tumors (EFT) is rarely diagnosed in patients (pts) over the age of 18 years (years), and data on the clinical course and the outcome of adult EFT pts is sparse.MethodsIn this retrospective analysis, we summarize our experience with adult EFT pts. From 2002 to 2020, we identified 71 pts of whom 58 were evaluable for the final analysis.ResultsMedian age was 31 years (18–90 years). Pts presented with skeletal (n = 26), and extra‐skeletal primary disease (n =32). Tumor size was ≥8 cm in 20 pts and 19 pts were metastasized at first diagnosis. Between the age groups (≤25 vs. 26–40 vs. ≥41 years) we observed differences of Charlson comorbidity index (CCI), tumor origin, as well as type and number of therapy cycles. Overall, median overall survival (OS) was 79 months (95% confidence interval, CI; 28.5–131.4 months), and median progression‐free survival (PFS) 34 months (95% CI; 21.4–45.8 months). We observed a poorer outcome (OS, PFS) in older pts. This could be in part due to differences in treatment intensity and the CCI (<3 vs. ≥3; hazard ratio, HR 0.334, 95% CI 0.15–0.72, p = 0.006). In addition, tumor stage had a significant impact on PFS (localized vs. metastasized stage: HR 0.403, 95% CI 0.18–0.87, p = 0.021).ConclusionsOur data confirms the feasibility of intensive treatment regimens in adult EFT pts. While in our cohort outcome was influenced by age, due to differences in treatment intensity, CCI, and tumor stage, larger studies are warranted to further explore optimized treatment protocols in adult EFT pts.

Advances in the classification of round cell sarcomas.

Round cell sarcomas represent a diagnostic challenge for pathologists, owing to the poorly differentiated features of these high-grade tumours. The diagnosis of round cell sarcoma requires large immunohistochemical panels and molecular testing in many cases. This spectrum of malignancies is largely dominated by Ewing sarcomas (ESs), which represent the most common family of these tumours. Nonetheless, new families have been delineated in the past few years, with the addition of two additional families in the 2020 World Health Organization classification of bone and soft tissue tumours, namely sarcomas with CIC rearrangements and sarcomas with BCOR alterations. EWSR1, one of the genes involved in the driver fusion of ESs, is also implicated in the translocation of many other tumours with heterogeneous lineages and variable levels of aggressiveness. Round cell sarcomas associated with fusions inwhichEWSR1is partnered with genes encoding transcription factors distinct from those of the 'Ewing family' represent a heterogeneous group of rare tumours that require further study to determine whether their fusions may or not define a specific subgroup. They include mainly sarcomas with NFATc2 rearrangements and sarcomas with PATZ1 rearrangements. At this point, PATZ1 fusions seem to be associated with tumours of high clinical and morphological heterogeneity. Molecular studies have also helped in the identification of more consistent biomarkers that give tremendous help to pathologists in triaging, if not diagnosing, these tumours in practice. This review compiles the latest accumulated evidence regarding round cell sarcomas, and discusses the areas that are still under investigation.

A-10-Year Review on Survival Rate and Prognostic Factors of Ewing Family Tumour in Children at Hospital Universiti Sains Malaysia

Introduction: Ewing Family Tumour (EFT) is a group of rare malignant and aggressive tumour, with a considerably improved prognosis. However, there is lack of study on the outcome of children with EFT in Malaysia. Objectives: The study aimed to evaluate the Overall Survival (OS) rate, Event Free Survival (EFS) rate and identify the prognostic factors that determined the EFT outcome at Hospital Universiti Sains Malaysia (USM). Methodology: A retrospective record review of children aged 0-18 years with EFT was done. Patients were identified from the registration data in the Oncology Unit and Record Office of Hospital USM. For patients with untraceable information or deceased, a letter was sent to State Registry to obtain the outcome of the patient. The association between demographics and patients’ clinical factors was determined using the Cox regression. Survival curves were estimated by the Kaplan-Meier method and were compared using the Log-rank test. Results: There were 51 patients identified but 29 of them were eligible for the study. The mean duration of follow-up was 21 months. The OS rate at 1, 2, 3 and 5 years were 62.1%, 44.8%, 30.2% and 21.6% respectively. The EFS rate at 1, 2, 3 and 5 years were 41.9%, 26.7%, 17.8% and 0% respectively. Multivariate Cox regression analysis showed that the presence of surgical intervention (p = 0.030) and major complications (p = 0.045) were the significant prognostic factors to the survival of EFT. Conclusion: The survival rate of EFT among our patients was comparable to other developing countries, with surgical intervention and the presence of major complications as independent prognostic factors.

Consensus on Indications for Hematopoietic Stem Cell Transplantation in Pediatrics. Update 2020: Sarcomas, Ewing Family Tumor, Osteosarcoma and Hepatoblastoma

The indications for hematopoietic stem cell transplantation in solid tumors in children do not change a lot since our first Brazilian consensus publication in 2009. In this article, we are going to review indications to hematopoietic stem cell transplantation in solid tumors, including the ones that had no more virtual indications.&#x0D; For the consensus, a review was made using the most relevant articles, and a series of meetings was done to discuss the recommendations.

EWSR1 rearrangement in papillary thyroid microcarcinoma is related to classic morphology and the presence of small-cell phenotype.

The Ewing sarcoma breakpoint region 1 (EWSR1) rearrangements with unknown genes were detected in a high percentage of classic variants of papillary thyroid carcinoma. The small-cell carcinoma of the thyroid with Ewing family tumor elements typically presents with EWSR1-FLI1 rearrangement suggesting the possible role of EWSR-FLI1 translocation in the loss of thyroid differentiation and acquisition of a small-cell phenotype. To determine the frequency and association of EWSR1 rearrangements, particularly the EWSR1-FLI1 fusion with clinicopathological features of papillary thyroid microcarcinoma (m-PTC) and the presence of small cells, we analyzed a series of 99 m-PTCs using the fluorescence in situ hybridization method. Ninety cases (90.9%) of m-PTC were positive for small cells. This group of m-PTC has shown more often invasive growth, lymphatics invasion, and moderate/extended intratumoral fibrosis. Three cases out of 99 were inconclusive for EWSR1 rearrangement. Eighty-nine (92.7%) and 27 (28.1%) out of 96 m-PTC cases were positive for EWSR1 rearrangement and EWSR1-FLI1 fusion, respectively. m-PTC with classical architectural pattern presented more frequently with EWSR1 rearrangement relative to m-PTC with other patterns (p = 0.005). Other clinicopathological features were not related to the presence of EWSR1 rearrangement or EWSR1-FLI1 fusion. The percentage of small cells present significantly correlated with the percentage of cells positive for EWSR1-FLI1 fusion (p = 0.05) and EWSR1 rearrangement (p < 0.001). EWSR1-FLI1 fusion is not rare in m-PTC and it is associated with the acquisition of small-cell phenotype. The EWSR1 gene rearrangement is a frequent event in m-PTC and is related to the classical pattern of m-PTC.

Bone marrow trephine immunohistochemistry is useful in characterizing malignancy-associated myelonecrosis: A retrospective observational study.

We aim to describe the utility of immunohistochemistry (IHC) in characterizing malignancy-associated myelonecrosis (MN) on bone marrow trephine biopsies (BMBx) as a part of initial workup. Patten and intensity of antigenic immunoexpression in necrotic tumor cells on BMBx were evaluated in a series of cases using standardized avidin-biotin-complex immunoperoxidase technique after heat-induced epitope retrieval and compared the same with viable tumor cells wherever available. Fifteen out of 2494 (0.6%) cases (median age: 28years; range: 4 to 66years) had evidence of MN (extensive in eight, moderate in five, and focal in two) secondary to hematological (N=9) and solid (N=6) malignancies. Five (33.3%) had pancytopenia, and eight (53.3%) had difficult and/or hemodiluted aspirate. Antigenic expression for CD10, CD79a, CD3, CD7, and CD20 was retained by necrotic leukemic blasts or lymphoma cells; CD34, TdT, and PAX5 showed heterogeneous expression; and a weak Golgi zone (dot like) CD30 positivity was noted in Reed-Sternberg (RS) or RS-like giant cells. Necrotic epithelial metastases retained pancytokeratin in all and showed variable positivity for prostate-specific antigen, carcinoembryonic antigen, CK20, ER, PR, and GATA3. Necrotic neuroblastomas (N=2) retained positivity for synaptophysin and chromogranin, whereas retained nuclear positivity for NKX2.2 in necrotic Ewing family of tumor (N=1) aided in early diagnosis. Myelonecrosis may retain tumor antigenicity, and immunohistochemistry using selected panel of antibodies should be tried in such challenging cases for an early presumptive diagnosis and further decision making.

Ewing family tumors of the appendicular skeleton: a retrospective analysis of prognostic factors.

Authors retrospectively analyzed possible prognostic factors in a series of patients affected by Ewing sarcoma of extremities (eEWS) and treated over a 20-year period at a single institution. Between 1997 and 2017, 88 bone eEWS were treated at our institution. Staging, age, gender, tumoral volume, local treatment, surgical margins, post-ChT necrosis were investigated for prognostic correlation with overall survival (OS) and event-free survival (EFS). Median follow-up was 74months (1-236). Staging of disease correlated with OS (81% vs 59%, p = 0.01) and not with EFS (68% vs 57%, p = 0.28) in localized vs metastatic eEWS at presentation. Age ≥ 14years (p = 0.002) and volume ≥ 100 cm3 (p = 0.04) were significant negative prognostic factors. No difference was found in local treatment: OS was 76% vs 63% (p = 0.33), while EFS was 68% vs 49% (p = 0.06) after surgery alone or surgery + radiotherapy, respectively. Regarding surgical margins, OS was 76% vs 38% (p = 0.14), and EFS was 65% vs 33% (p = 0.14) in adequate vs not adequate, respectively. OS was 86% and 68% in good and poor responders, respectively (p = 0.13). In eEWS, metastatic disease at presentation, age > 14years and tumoral volume > 100 cm3 are negative prognostic factors. Intensified adjuvant ChT can improve prognosis in poor responders and metastatic patients.

Multiscale-omic assessment of EWSR1-NFATc2 fusion positive sarcomas identifies the mTOR pathway as a potential therapeutic target

Sarcomas harboring EWSR1-NFATc2 fusions have historically been categorized and treated as Ewing sarcoma. Emerging evidence suggests unique molecular characteristics and chemotherapy sensitivities in EWSR1-NFATc2 fusion positive sarcomas. Comprehensive genomic profiles of 1024 EWSR1 fusion positive sarcomas, including 14 EWSR1-NFATc2 fusions, were identified in the FoundationCore® database. Additional data from the Gene Expression Omnibus, the Genomics of Drug Sensitivity in Cancer and The Cancer Genome Atlas datasets were included for analysis. EWSR1-NFATc2 fusion positive sarcomas were genomically distinct from traditional Ewing sarcoma and demonstrated upregulation of the mTOR pathway. We also present a case of a 58-year-old male patient with metastatic EWSR1-NFATc2 fusion positive sarcoma who achieved 47 months of disease stabilization when treated with combination mTOR and VEGF inhibition. EWSR1-NFATc2 fusion positive sarcomas are molecularly distinct entities with overactive mTOR signaling; which may be therapeutically targetable. These findings support the use of precision medicine in the Ewing family of tumors.

Adolescent-adult nonmetastatic Ewing sarcoma-Experience from a large developing country.

Outcome and toxicity data in adolescent-adult Ewing sarcoma (AA-ES) patients are sparse and merits exploration. Histopathologically confirmed, nonmetastatic AA-ES patients, who received standard institutional combination chemotherapy regimen (Ewing's family of tumors-2001 [EFT-2001]) comprising of ifosfamide plus etoposide and vincristine, doxorubicin plus cyclophosphamide, lasting a total of 12months between 2013 and 2018, were analyzed for treatment-related toxicities, event-free survival (EFS), and overall survival (OS). There were 235 patients (primary safety cohort [PSC]) with median age of 23 (15-61) years; 159 (67.7%) were males, 155 (65.9%) had skeletal primary and 114 (48.5%) had extremity tumors. One hundred ninety-six (83.4%) were treatment naïve (primary efficacy cohort [PEC]) and of these 119 (60.7%) had surgery. In PEC, at a median follow-up of 36.4 (interquartile range [IQR] 20-55) months, estimated 3-year EFS and OS were 67.3% (95% CI 60.3-75.1%) and 91.1% (95% CI 86.7-95.7%), respectively. Of these, 158 (80.6%) complying with intended treatment, at a median follow-up of 39 (IQR 26-57) months had an estimated 3-year EFS of 68.2% (95% CI 60.3-76.1%). In multivariable analysis, good prognostic factors included longer symptom(s) duration (HR 0.93, 95% CI 0.86-0.994), ≥99% necrosis (HR 0.30, 95% CI 0.11-0.77), and treatment completion (HR 0.32, 95% CI 0.14-0.74). Among PSC, grade 3-4 toxicities were febrile neutropenia (119, 50.6%), anemia (130, 55.3%), peripheral neuropathy (37, 15.7%), with three (1.3%) chemo-toxic deaths. The outcomes of AA nonmetastatic ES patients treated with EFT-2001 regimen were comparable to those reported by others, with acceptable toxicity. This regimen can be considered a standard of care in AA-ES.