Current therapeutic approaches in metastatic and recurrent ewing sarcoma

Factors Influencing the Outcome of Patients with Primary Ewing Sarcoma of the Sacrum

Background

Ewing sarcoma (EwS) is a rare and highly malignant bone tumor primarily affecting children, adolescents, and young adults. The pelvis, trunk, and lower extremities are the most common sites, while EwS of the sacrum as a primary site is very rare, and only few studies focusing on this location are published. Due to the anatomical condition, local treatment is challenging in sacral malignancies. We analyzed factors that might influence the outcome of patients suffering from sacral EwS.

Methods

We retrospectively analyzed data of the GPOH EURO-E.W.I.N.G 99 trial and the EWING 2008 trial, with a cohort of 124 patients with localized or metastatic sacral EwS. The study endpoints were overall survival (OS) and event-free survival (EFS). OS and EFS were calculated using the Kaplan-Meier method, and univariate comparisons were estimated using the log-rank test. Hazard ratios (HRs) with respective 95% confidence intervals (CIs) were estimated in a multivariable Cox regression model.

Results

The presence of metastases (3y-EFS: 0.33 vs. 0.68; P < 0.001; HR = 3.4, 95% CI 1.7 to 6.6; 3y-OS: 0.48 vs. 0.85; P < 0.001; HR = 4.23, 95% CI 1.8 to 9.7), large tumor volume (≥200 ml) (3y-EFS: 0.36 vs. 0.69; P=0.02; HR = 2.1, 95% CI 1.1 to 4.0; 3y-OS: 0.42 vs. 0.73; P=0.04; HR = 2.1, 95% CI 1.03 to 4.5), and age ≥18 years (3y-EFS: 0.41 vs. 0.60; P=0.02; HR = 2.6, 95% CI 1.3 to 5.2; 3y-OS: 0.294 vs. 0.59; P=0.01; HR = 2.92, 95% CI 1.29 to 6.6) were revealed as adverse prognostic factors.

Conclusion

Young age seems to positively influence patients` survival, especially in patients with primary metastatic disease. In this context, our results support other studies, stating that older age has a negative impact on survival. Tumor volume, metastases, and the type of local therapy modality have an impact on the outcome of sacral EwS. Level of evidence: Level 2. This trial is registered with NCT00020566 and NCT00987636.

Exploiting the Stemness and Chemoresistance Transcriptome of Ewing Sarcoma to Identify Candidate Therapeutic Targets and Drug-Repurposing Candidates

Outcomes for most patients with Ewing sarcoma (ES) have remained unchanged for the last 30 years, emphasising the need for more effective and tolerable treatments. We have hypothesised that using small-molecule inhibitors to kill the self-renewing chemotherapy-resistant cells (Ewing sarcoma cancer stem-like cells; ES-CSCs) responsible for progression and relapse could improve outcomes and minimise treatment-induced morbidities. For the first time, we demonstrate that ABCG1, a potential oncogene in some cancers, is highly expressed in ES-CSCs independently of CD133. Using functional models, transcriptomics and a bespoke in silico drug-repurposing pipeline, we have prioritised a group of tractable small-molecule inhibitors for further preclinical studies. Consistent with the cellular origin of ES, 21 candidate molecular targets of pluripotency, stemness and chemoresistance were identified. Small-molecule inhibitors to 13 of the 21 molecular targets (62%) were identified. POU5F1/OCT4 was the most promising new therapeutic target in Ewing sarcoma, interacting with 10 of the 21 prioritised molecular targets and meriting further study. The majority of small-molecule inhibitors (72%) target one of two drug efflux proteins, p-glycoprotein (n = 168) or MRP1 (n = 13). In summary, we have identified a novel cell surface marker of ES-CSCs and cancer/non-cancer drugs to targets expressed by these cells that are worthy of further preclinical evaluation. If effective in preclinical models, these drugs and drug combinations might be repurposed for clinical evaluation in patients with ES.

High-dose chemotherapy followed by autologous stem cell transplantation for adult patients With first relapse of Ewing's sarcoma: A single institution experience

The prognosis of patients with Ewing's sarcoma family of tumors (ESFT) relapse is poor; the 5-year overall survival (OS) is 13%. We evaluated the effectivity of high-dose therapy (HDT) with autologous stem cell transplantation (ASCT) in adult patients with ESFT relapse. Between January 2010 and January 2021, we retrospectively analyzed 20 patients with ESFT who received HDT upon relapse. A combination of busulfan with melphalan was used as a conditioning regimen before ASCT. The median follow-up from diagnosis and from first relapse was 46.08 months (range; 10.71-186.87) and 14.41 months (range; 4.34-104.11), respectively. The median of age patients was 21.2 years (range, 17.6-25.3), and 10 (50%) patients were female. The tumor originated from the bone in 13 patients and soft tissue in 7 patients. Twelve patients had early (<2 years) relapse, and 8 patients had late (>2 years) relapse. Before HDT, 13 (65%) and 7 (35%) patients had pulmonary and extrapulmonary metastasis, respectively. After induction chemotherapy, 14 patients achieved complete response. The median OS1 and OS2 were 51.6 months (95% confidence interval [CI], range: 16.2-87) and 15.7 months (95% CI, range: 10.2-21.2), respectively. The 1-, 2-, and 5-year OS rates were 50%, 30%, and 15%, respectively. One patient died (sepsis) 1 month after ASCT. In univariate analyses, a disease-free interval (DFI) of < 2 years (P = .008) and incomplete response (P = .021) before ASCT were poor prognostic factors for OS2.HDT with ASCT can result in long-term survival of patients with ESFT relapse. HDT should be considered an important treatment opt ion in patients with a DFI > 2 years and complete response before transplantation.

Survival Outcomes in Metastatic Ewing Sarcoma Treated With Whole-Lung Radiation

Background and objective

There is a scarcity of research on outcomes in patients with metastatic Ewing sarcoma limited to pulmonary metastases who receive whole-lung radiotherapy (WLRT). In light of this, this study aimed to evaluate the use of WLRT and compare the survival outcomes between patients with metastatic Ewing sarcoma who received treatment with WLRT and those who did not.

Materials and methods

Patients of all ages with metastatic Ewing sarcoma restricted to the lung who were referred to the British Columbia (BC) Cancer from 1995 to 2017 were identified from the Sarcoma Outcomes Unit (SARCOU). Patient demographics and tumor and treatment characteristics were compared between cohorts treated with WLRT versus those who did not undergo WLRT. Five-year progression-free survival (PFS) and overall survival (OS) were evaluated using Kaplan-Meier (KM) estimates and compared between treatment groups with log-rank tests.

Results

The study cohort comprised 30 patients (median follow-up time: 6.8 years). Overall, the median age of the patients was 16 years (range: 4-86 years) and 60% were female; the primary disease sites were as follows: 27% axial skeleton, 53% appendicular skeleton, 20% visceral, 86% had ≥2 lung metastases, and 60% had bilateral disease. Fifteen (50%) patients received WLRT (median of 1500 cGy in 10 fractions). Chemotherapy was used in 97% of patients. The rate of surgery for lung metastases was 40%, which was similar between the WLRT and non-WLRT groups. The median size of the largest lung metastasis in the WLRT cohort was 1 cm (range: 0.3-1.8 cm), compared to 2 cm (range 0.5-6.7 cm) in the non-WLRT cohort (p=0.05). Demographics and tumor characteristics were otherwise not significantly different between the two treatment groups (all p>0.05). Among patients who received WLRT, 53% had complete response (CR), 7% partial response (PR), and 40% had disease progression. The five-year PFS was 86% vs. 59% (p=0.33) and OS was 78% vs. 54% (p=0.24) respectively for patients in the WLRT group vs. those in the non-WLRT group. The five-year PFS outcomes were higher on univariate analysis in patients with appendicular skeletal compared to axial skeletal and visceral primary sites (87.5% vs. 58% vs. 50%, respectively, p=0.02) and in patients with the size of the largest lung metastasis <2 cm vs. those with a size ≥2 cm (80% vs. 25%, p=0.04).

Conclusions

Patients treated with WLRT had a smaller-volume lung disease and over half of the patients who received WLRT had either complete or partial response. Trends of improved PFS and OS at five years were observed among patients who received WLRT compared to the non-WLRT group, but these were not statistically significant.

Mechanisms, Diagnosis and Treatment of Bone Metastases

Bone and bone marrow are among the most frequent metastatic sites of cancer. The occurrence of bone metastasis is frequently associated with a dismal disease outcome. The prevention and therapy of bone metastases is a priority in the treatment of cancer patients. However, current therapeutic options for patients with bone metastatic disease are limited in efficacy and associated with increased morbidity. Therefore, most current therapies are mainly palliative in nature. A better understanding of the underlying molecular pathways of the bone metastatic process is warranted to develop novel, well-tolerated and more successful treatments for a significant improvement of patients' quality of life and disease outcome. In this review, we provide comparative mechanistic insights into the bone metastatic process of various solid tumors, including pediatric cancers. We also highlight current and innovative approaches to biologically targeted therapy and immunotherapy. In particular, we discuss the role of the bone marrow microenvironment in the attraction, homing, dormancy and outgrowth of metastatic tumor cells and the ensuing therapeutic implications. Multiple signaling pathways have been described to contribute to metastatic spread to the bone of specific cancer entities, with most knowledge derived from the study of breast and prostate cancer. However, it is likely that similar mechanisms are involved in different types of cancer, including multiple myeloma, primary bone sarcomas and neuroblastoma. The metastatic rate-limiting interaction of tumor cells with the various cellular and noncellular components of the bone-marrow niche provides attractive therapeutic targets, which are already partially exploited by novel promising immunotherapies.

Ewing's sarcoma of the hip: A case report with no evidence of tumor recurrence and literature review

Background

Ewing's sarcoma (ES) of the hip and trochanteric region is a rare malignancy. The tumor has a poor prognosis due to the problems in early diagnosis and medical intervention.

Case presentation

This paper reports a rare case of hip ES presented in a 34y/o female. The clinical, radiological, and histopathological features were all in favor of ES. Following treatment by neoadjuvant/adjuvant chemotherapy, and irradiation the patient is now with complete resolution of the tumor.

Conclusion

The patient remained free of disease through 4 years of follow-up until now after diagnosis.

Irinotecan and temozolomide chemotherapy in paediatric and adult populations with relapsed Ewing Sarcoma

BACKGROUND

Irinotecan and temozolomide (IT) is a widely used regimen for relapsed Ewing sarcoma (ES), although studies are largely limited to paediatric populations.

METHODS

We retrospectively reviewed paediatric (< 18 years) and adult patients (≥ 18 years) treated with salvage IT at two institutions. Haematologic toxicities were graded according to common terminology criteria of adverse events. Survival was estimated by the Kaplan-Meier method and compared by the Log Rank test.

RESULTS

Fifty-three patients were treated with IT from Jan, 2010 to Dec, 2018 (n = 16 paediatric; n = 37 adult). IT was given as second-line (n = 34; 64%) or ≥ third-line (n = 19; 36%). There was no difference in ≥ grade 3/4 haematologic toxicity between paediatrics and adults (31% vs. 35% respectively; p = 0.76). The frequency of diarrhoea of any grade was similar (38% in each group). Of 43 patients assessable for response, 12 (28%) had objective response (1 CR, 11 PR), 12 (28%) stable disease and 19 (44%) disease progression. Objective response rate did not differ between the two groups (36% in paediatrics vs. 25% in adults; p = 0.47). Median PFS was superior in paediatrics vs. adults (7.4 vs. 2.2 months, p = 0.039).

CONCLUSION

Irinotecan and temozolomide (IT) chemotherapy has activity for relapsed ES, with favourable toxicity and equally observed objective responses in the paediatric and adult populations. The observed superior PFS for the paediatric cohort requires further confirmation in future studies.

New insights into antimetastatic signaling pathways of melatonin in skeletomuscular sarcoma of childhood and adolescence

Melatonin is an indole produced by the pineal gland at night under normal light or dark conditions, and its levels, which are higher in children than in adults, begin to decrease prior to the onset of puberty and continue to decline thereafter. Apart from circadian regulatory actions, melatonin has significant apoptotic, angiogenic, oncostatic, and antiproliferative effects on various cancer cells. Particularly, the ability of melatonin to inhibit skeletomuscular sarcoma, which most commonly affects children, teenagers, and young adults, is substantial. In the past few decades, the vast majority of references have focused on the concept of epithelial-mesenchymal transition involvement in invasion and migration to allow carcinoma cells to dissociate from each other and to degrade the extracellular matrix. Recently, researchers have applied this idea to sarcoma cells of mesenchymal origin, e.g., osteosarcoma and Ewing sarcoma, with their ability to initiate the invasion-metastasis cascade. Similarly, interest of the effects of melatonin has shifted from carcinomas to sarcomas. Herein, in this state-of-the-art review, we compiled the knowledge related to the molecular mechanism of antimetastatic actions of melatonin on skeletomuscular sarcoma as in childhood and during adolescence. Utilization of melatonin as an adjuvant with chemotherapeutic drugs for synergy and fortification of the antimetastatic effects for the reinforcement of therapeutic actions are considered.

Identifying States of Collateral Sensitivity during the Evolution of Therapeutic Resistance in Ewing's Sarcoma

Advances in the treatment of Ewing's sarcoma (EWS) are desperately needed, particularly in the case of metastatic disease. A deeper understanding of collateral sensitivity, where the evolution of therapeutic resistance to one drug aligns with sensitivity to another drug, may improve our ability to effectively target this disease. For the first time in a solid tumor, we produced a temporal collateral sensitivity map that demonstrates the evolution of collateral sensitivity and resistance in EWS. We found that the evolution of collateral resistance was predictable with some drugs but had significant variation in response to other drugs. Using this map of temporal collateral sensitivity in EWS, we can see that the path toward collateral sensitivity is not always repeatable, nor is there always a clear trajectory toward resistance or sensitivity. Identifying transcriptomic changes that accompany these states of transient collateral sensitivity could improve treatment planning for patients with EWS.

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Ewing's sarcoma cell lines were evolved to become resistant to standard chemotherapy

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A temporal collateral sensitivity map shows response to alternative drugs over time

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Collateral drug response is repeatable in some instances and stochastic in others

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Differential gene expression elucidates potential biomarkers of drug response

Adamantinoma-like Ewing sarcoma of the thyroid

Adamantinoma-like Ewing sarcoma (ALES) is a rare variant of Ewing sarcoma family of tumors (ESFTs). ALES is characterized by translocations of the EWSR1 (Ewing sarcoma breakpoint region 1) gene on chromosome 22, morphologic features of small round blue cell tumors with focal squamous differentiation, and a unique immunoprofile. Herein, we report a 21-year-old patient who presented with severe, acute onset back pain. Imaging revealed a large, exophytic, heterogeneously enhancing mass in the left thyroid and numerous lytic bone lesions. Fine-needle aspiration of the thyroid, revealed a cellular smear with "small round blue cell" morphology. The unique immunoprofile of positive ESFT markers (NKX2.2 and CD99), along with positive markers of squamous epithelial differentiation (AE1/AE3 and p40), led to a diagnosis of ALES. This was confirmed by fluorescence in situ hybridization, which demonstrated EWSR1 rearrangement in 74% of nuclei.

Phase II results from a phase I/II study to assess the safety and efficacy of weekly nab-paclitaxel in paediatric patients with recurrent or refractory solid tumours: A collaboration with the European Innovative Therapies for Children with Cancer Network

BACKGROUND

The phase I component of a phase I/II study defined the recommended phase II dose and established the tolerability of nab-paclitaxel monotherapy in paediatric patients with recurrent or refractory solid tumours. The activity and safety of nab-paclitaxel monotherapy was further investigated in this phase II study.

PATIENTS AND METHODS

Paediatric patients with recurrent or refractory Ewing sarcoma, neuroblastoma or rhabdomyosarcoma received 240 mg/m² of nab-paclitaxel on days 1, 8 and 15 of each 28-day cycle. The primary end-point was the overall response rate (ORR; complete response [CR] + partial response [PR]). Secondary end-points included duration of response, disease control rate (DCR; CR + PR + stable disease [SD]), progression-free survival, 1-year overall survival, safety and pharmacokinetics.

RESULTS

Forty-two patients were enrolled, 14 each with Ewing sarcoma, neuroblastoma and rhabdomyosarcoma. The ORRs were 0%, 0% and 7.1% (1 confirmed PR), respectively. The DCRs were 30.8% (4 SD), 7.1% (1 SD) and 7.1% (1 confirmed PR and 0 SD) in the Ewing sarcoma, neuroblastoma and rhabdomyosarcoma groups, respectively. The median progression-free survival was 13.0, 7.4 and 5.1 weeks, respectively, and the 1-year overall survival rates were 48%, 25% and 15%, respectively. The most common grade III/4IVadverse events were haematologic (neutropenia [50%] and anaemia [48%]), and grade III/IV peripheral neuropathy occurred in 2 patients (14%) in the rhabdomyosarcoma group. Pharmacokinetics analyses revealed that paclitaxel tissue distribution was both rapid and extensive.

CONCLUSIONS

In this phase II study, limited activity was observed; however, the safety of nab-paclitaxel in paediatric patients was confirmed.

TRIAL REGISTRATION

NCT01962103 and EudraCT 2013-000144-26.

Soft Tissue Special Issue: Adamantinoma-Like Ewing Sarcoma of the Head and Neck: A Practical Review of a Challenging Emerging Entity

Adamantinoma-like Ewing sarcoma (ALES) is a rare variant of Ewing sarcoma that is defined by complex epithelial differentiation, including expression of cytokeratin and p40 and frequent keratin pearl formation. In recent years, ALES has been increasingly recognized in the head and neck, where it can mimic a wide range of small round blue cell tumors and basaloid carcinomas. However, there has been persistent controversy regarding whether ALES is best classified and managed as a sarcoma or carcinoma. This review summarizes the characteristic clinical, pathologic, immunophenotypic, and molecular features of ALES with an emphasis on differential diagnosis and tumor classification.

Adamantinoma-like Ewing Sarcoma of the Salivary Glands: A Newly Recognized Mimicker of Basaloid Salivary Carcinomas

Adamantinoma-like Ewing sarcoma (ALES) is a rare tumor that demonstrates the EWSR1-FLI1 translocation characteristic of Ewing sarcoma despite overt epithelial differentiation including diffuse expression of cytokeratins and p40. Most cases of ALES described to date have occurred in the head and neck where they can mimic a wide range of small round blue cell tumors. Because distinguishing ALES from basaloid salivary gland carcinomas can be particularly difficult, we analyzed a series of 10 ALESs that occurred in the salivary glands with the aim of identifying features that allow for better recognition of this entity. The salivary ALESs included 8 parotid gland and 2 submandibular gland tumors in patients ranging from 32 to 77 years (mean: 52 y). Nine were initially misclassified as various epithelial neoplasms. Although these tumors displayed the basaloid cytology, rosette formation, infiltrative growth, and nuclear monotony characteristic of ALES, peripheral palisading and overt keratinization were relatively rare in this site. Salivary ALESs not only displayed positivity for AE1/AE3, p40, and CD99, but also demonstrated a higher proportion of synaptophysin reactivity than has been reported for nonsalivary ALESs. These morphologic and immunohistochemical findings make ALES susceptible to misclassification as various other tumors including basal cell adenocarcinoma, adenoid cystic carcinoma, squamous cell carcinoma, NUT carcinoma, large cell neuroendocrine carcinoma and myoepithelial carcinoma. Nevertheless, monotonous cytology despite highly infiltrative growth and concomitant positivity for p40 and synaptophysin can provide important clues for consideration of ALES, and identification of the defining EWSR1-FLI1 translocations can confirm the diagnosis.

Synchronous extraskeletal Ewing's sarcoma/PNET and gallbladder carcinoma: a case report and literature review

Ewing’s sarcoma (ES) and primitive neuroectodermal tumour (PNET) are now considered to be the same tumour and usually occur in long bones. Extraskeletal Ewing’s sarcoma is an extremely rare neoplasm, accounting for 1% of soft tissue sarcomas, with most common location in the thorax. Gallbladder cancer (GBC) represents the most common type among the biliary tract cancers with a poor prognosis even among patients undergoing aggressive therapy.

We present study of extraskeletal ES/PNET found in the hilus of the liver of an elderly, diagnosed one month prior with GBC woman. The patient underwent two cycles of chemotherapy SAIME/SAVAC for ES and thereafter was operated. During three-year follow-up no recurrence of ES/PNET has been reported. However, two years after chemotherapy the patient suffered a relapse of adenocarcinoma of the gallbladder and thus received palliative chemotherapy of gemcitabine and cisplatin. After 16 months of recurrence she died. To the best of our knowledge, this is the first case of ES/PNET located in the hilus of the liver and as a synchronous neoplasm.

Molecular Changes Associated With Tumor Initiation and Progression of Soft Tissue Sarcomas: Targeting the Genome and Epigenome

Soft tissue sarcomas are rare, but generally aggressive tumors which disproportionately affect children and young adults. They represent less than 10% of all cancers, but are one of the most frequently diagnosed cancers in pediatric patients. These cancers have a high rate of morbidity and mortality, and their overall incidence has been increasing at an estimated rate of 26% over the last 2 decades. The cause of this increased incidence is unknown but various environmental factors have been implicated. Establishing standard therapeutic strategies is challenging for soft tissue sarcomas as more than 50 different histological subtypes exist, each with their own molecular alterations and clinical characteristics, and this combination of tumor heterogeneity and a limited number of clinical cases make detailed omics level molecular studies particularly challenging. This chapter will focus on the unique genetic and epigenetic changes which characterize these cancers, with an emphasis on translocation-associated sarcomas involving primary gene fusions with the RNA chaperone protein EWSR1. We will highlight current therapeutic approaches and discuss opportunities for targeted molecular therapeutics.

Recently described neoplasms of the sinonasal tract

Surgical pathology of the sinonasal region (i.e., nasal cavity and the paranasal sinuses) is notoriously difficult, due in part to the remarkable diversity of neoplasms that may be encountered in this area. In addition, a number of neoplasms have been only recently described in the sinonasal tract, further compounding the difficulty for pathologists who are not yet familiar with them. This manuscript will review the clinicopathologic features of some of the recently described sinonasal tumor types: NUT midline carcinoma, HPV-related carcinoma with adenoid cystic-like features, SMARCB1 (INI-1) deficient sinonasal carcinoma, biphenotypic sinonasal sarcoma, and adamantinoma-like Ewing family tumor.

EWING'S SARCOMA: EPIDEMIOLOGY AND PROGNOSIS FOR PATIENTS TREATED AT THE PEDIATRIC ONCOLOGY INSTITUTE, IOP-GRAACC-UNIFESP

Objective: To outline the epidemiological profile and prognosis for Ewing's sarcoma in the Brazilian population. Material and Methods: The medical records of 64 patients with intraosseous Ewing's sarcoma who were treated at the Pediatric Oncology Institute, IOP-GRAACC-Unifesp, between 1995 and 2010, were retrospectively evaluated. Results: The statistical analysis on the data obtained did not correlate factors such as sex, trauma, pathological fracture and time taken for case diagnosis with the treatment outcome. Factors such as initial metastasis, lung metastasis, tumor site, age, recurrence and type of surgery showed results corroborating what has been established in the literature. Conclusion: The prognosis in cases of Ewing's sarcoma was mainly influenced by the presence of metastases at the time of diagnosis.

Adamantinoma-like Ewing family tumors of the head and neck: a pitfall in the differential diagnosis of basaloid and myoepithelial carcinomas

Ewing sarcoma family tumors (EFTs) of the head and neck are rare and may be difficult to diagnose, as they display significant histologic overlap with other more common undifferentiated small blue round cell malignancies. Occasionally, EFTs may exhibit overt epithelial differentiation in the form of diffuse cytokeratin immunoexpression or squamous pearls, resembling the so-called adamantinoma-like EFTs and being challenging to distinguish from bona fide carcinomas. Furthermore, the presence of EWSR1 gene rearrangement correlated with strong keratin expression may suggest a myoepithelial carcinoma. Herein, we analyze a series of 7 adamantinoma-like EFTs of the head and neck, most of them being initially misdiagnosed as carcinomas because of their anatomic location and strong cytokeratin immunoexpression, and subsequently reclassified as EFT by molecular techniques. The tumors arose in the sinonasal tract (n=2), parotid gland (n=2), thyroid gland (n=2), and orbit (n=1), in patients ranging in age from 7 to 56 years (mean, 31 y). Microscopically, they departed from the typical EFT morphology by growing as nests with peripheral nuclear palisading and prominent interlobular fibrosis, imparting a distinctly basaloid appearance. Moreover, 2 cases exhibited overt keratinization in the form of squamous pearls, and 1 sinonasal tumor demonstrated areas of intraepithelial growth. All cases were positive for CD99, pancytokeratin, and p40. A subset of cases showed synaptophysin, S100 protein, and/or p16 reactivity, further confounding the diagnosis. Fluorescence in situ hybridization assays showed EWSR1 and FLI1 rearrangements in all cases. Our results reinforce that a subset of head and neck EFTs may show strong cytokeratin expression or focal keratinization, and are therefore histologically indistinguishable from more common true epithelial neoplasms. Thus, CD99 should be included in the immunopanel of a round cell malignancy regardless of strong cytokeratin expression or anatomic location, and a strong and diffuse CD99 positivity should prompt molecular testing for the presence of EWSR1 gene rearrangements.

The adolescent and young adult with cancer: state of the art -- bone tumors

Primary malignant bone tumors in the pediatric to young adult populations are relatively uncommon and account for about 6 % of all cancers in those less than 20 years old [1] and 3 % of all cancers in adolescents and young adults (AYA) within the age range of 15 to 29 years [2]. Osteosarcoma (OS) and Ewing's sarcoma (ES) comprise the majority of malignant bone tumors. The approach to treatment for both tumors consists of local control measures (surgery or radiation) as well as systemic therapy with high-dose chemotherapy. Despite earlier advances, there have been no substantial improvements in outcomes over the past several decades, particularly for patients with metastatic disease. This review summarizes the major advances in the treatment of OS and ES and the standard therapies available today, current active clinical trials, and areas of investigation into molecularly targeted therapies.

The adolescent and young adult with cancer: state of the art -- bone tumors

Primary malignant bone tumors in the pediatric to young adult populations are relatively uncommon and account for about 6 % of all cancers in those less than 20 years old [1] and 3 % of all cancers in adolescents and young adults (AYA) within the age range of 15 to 29 years [2]. Osteosarcoma (OS) and Ewing's sarcoma (ES) comprise the majority of malignant bone tumors. The approach to treatment for both tumors consists of local control measures (surgery or radiation) as well as systemic therapy with high-dose chemotherapy. Despite earlier advances, there have been no substantial improvements in outcomes over the past several decades, particularly for patients with metastatic disease. This review summarizes the major advances in the treatment of OS and ES and the standard therapies available today, current active clinical trials, and areas of investigation into molecularly targeted therapies.

Membrane expression of MRP-1, but not MRP-1 splicing or Pgp expression, predicts survival in patients with ESFT

Background:

Primary Ewing's sarcoma family of tumours (ESFTs) may respond to chemotherapy, although many patients experience subsequent disease recurrence and relapse. The survival of ESFT cells following chemotherapy has been attributed to the development of resistant disease, possibly through the expression of ABC transporter proteins.

Methods:

MRP-1 and Pgp mRNA and protein expression in primary ESFTs was determined by quantitative reverse-transcriptase PCR (RT-qPCR) and immunohistochemistry, respectively, and alternative splicing of MRP-1 by RT-PCR.

Results:

We observed MRP-1 protein expression in 92% (43 out of 47) of primary ESFTs, and cell membrane MRP-1 was highly predictive of both overall survival (P<0.0001) and event-free survival (P<0.0001). Alternative splicing of MRP-1 was detected in primary ESFTs, although the pattern of splicing variants was not predictive of patient outcome, with the exception of loss of exon 9 in six patients, which predicted relapse (P=0.041). Pgp protein was detected in 6% (38 out of 44) of primary ESFTs and was not associated with patient survival.

Conclusion:

For the first time we have established that cell membrane expression of MRP-1 or loss of exon 9 is predictive of outcome but not the number of splicing events or expression of Pgp, and both may be valuable factors for the stratification of patients for more intensive therapy.

The clone wars - revenge of the metastatic rogue state: the sarcoma paradigm

Ewing sarcoma (ES) is the second most common bone tumor affecting primarily adolescents and young adults. Despite recent advances in biological understanding, intensification of chemotherapeutic treatments, and progress in local control with surgery and/or radiation therapy, patients with metastatic or recurrent ES continue to have a dismal prognosis with less than 20% overall survival. All ES is likely metastatic at diagnosis although our methods of detection and classification may not account for this. Progressive disease may arise via a combination of: (1) selection of chemotherapy-resistant clones in primary tumor, (2) signaling from bone or lung microenvironments that may attract tumor cells to distant locations, and/or (3) genetic changes within the ES cells themselves due to DNA-damaging chemotherapeutic agents or other “hits.” These possibilities and the evidence base to support them are explored.

Detection of N-glycolyl GM3 ganglioside in neuroectodermal tumors by immunohistochemistry: an attractive vaccine target for aggressive pediatric cancer

The N-glycolylated ganglioside NeuGc-GM3 has been described in solid tumors such as breast carcinoma, nonsmall cell lung cancer, and melanoma, but is usually not detected in normal human cells. Our aim was to evaluate the presence of NeuGc-GM3 in pediatric neuroectodermal tumors by immunohistochemistry. Twenty-seven archival cases of neuroblastoma and Ewing sarcoma family of tumors (ESFT) were analyzed. Formalin-fixed, paraffin-embedded tumor samples were cut into 5 μm sections. The monoclonal antibody 14F7, a mouse IgG1 that specifically recognizes NeuGc-GM3, and a peroxidase-labeled polymer conjugated to secondary antibodies were used. Presence of NeuGc-GM3 was evident in 23 of 27 cases (85%), with an average of about 70% of positive tumors cells. Immunoreactivity was moderate to intense in most tumors, showing a diffuse cytoplasmic and membranous staining, although cases of ESFT demonstrated a fine granular cytoplasmic pattern. No significant differences were observed between neuroblastoma with and without NMYC oncogene amplification, suggesting that expression of NeuGc-GM3 is preserved in more aggressive cancers. Until now, the expression of N-glycolylated gangliosides in pediatric neuroectodermal tumors has not been investigated. The present study evidenced the expression of NeuGc-GM3 in a high proportion of neuroectodermal tumors, suggesting its potential utility as a specific target of immunotherapy.

Hemipelvectomy- only a salvage therapy?

After the first hemipelvectomy in 1891 significant advances have been made in the fields of preoperative diagnosis, surgical technique and adjuvant treatment in patients with pelvic tumors. The challenging surgical removal of these rare malignant bone or soft tissue tumors accompanied by interdisciplinary therapy is mostly the only chance of cure, but bares the risk of intensive bleeding and infection. The reconstruction after hemipelvectomy is of importance for the later outcome and quality of life for the patient. Here, plastic surgery with microvascular free flaps or local rotational flaps improved the reconstruction and reduced infection rates. Average local recurrence rates of 14% demonstrate good surgical results, but 5 year survival rates of only 50% are described for some tumor entities, showing the importance of a multimodal collaboration. On a basis of a selective literature review the history, indications, treatment options and outcome of hemipelvectomies are presented.