Association between local treatment modalities and event-free survival, overall survival, and local recurrence in patients with localised Ewing Sarcoma. Report from the Ewing 2008 trial.

BACKGROUND: Local treatment is a crucial element in the standard of care for Ewing sarcoma (EWS). While systemic treatment is improved in randomised clinical trials, local treatment modalities are discussed controversially. We analysed the association between local therapy and event-free survival (EFS), overall survival (OS), and local recurrence (LR) in prospectively collected data of patients with localised EWS. PATIENTS AND METHODS: We analysed data from the international Ewing 2008 study registered between 2009 and 2019 in 117 centres. After induction chemotherapy, patients received surgery, radiotherapy, or a combination thereof. We performed Cox regression, conducted propensity score-weighted sensitivity analysis, and performed subgroup analyses. Hazard ratios (HRs) and 95% confidence intervals are reported. RESULTS: We included 863 patients with localised EWS (surgery alone: 331, combination therapy: 358, definitive radiotherapy: 174). In patients treated with combination therapy compared to surgery alone, EFS HR was 0.84 (0.57-1.24; p = 0.38), OS HR was 0.84 (0.57-1.23; p = 0.41), and LR HR was 0.58 (0.26-1.31; p = 0.19). Hazards of any event were increased in patients treated with definitive radiotherapy compared to surgery only, HR 1.53 (1.02-2.31; p = 0.04). Patients with poor responses to chemotherapy benefitted from combination therapy over definitive surgery with an EFS HR 0.49 (0.27-0.89; p = 0.02). Patients with pelvic tumours benefitted from combination therapy over surgery only regarding LR, HR 0.12 (0.02-0.72; p = 0.02). CONCLUSION: Patients with poor responses to chemotherapy benefitted from radiotherapy added to surgery. In the whole group, radiotherapy alone as opposed to surgery alone increased the hazards of any event.

Ewing Sarcoma as Secondary Malignant Neoplasm-Epidemiological and Clinical Analysis of an International Trial Registry.

Ewing sarcoma (EwS) is the second most common bone and soft tissue tumor, affecting primarily adolescents and young adults. Patients with secondary EwS are excluded from risk stratification in several studies and therefore do not benefit from new therapies. More knowledge about patients with EwS as secondary malignant neoplasms (SMN) is needed to identify at-risk patients and adapt follow-up strategies. Epidemiology, clinical characteristics, and survival analyses of EwS as SMN were analyzed in 3844 patients treated in the last three consecutive international EwS trials, EICESS 92, Euro-E.W.I.N.G. 99, and EWING 2008. Forty-two cases of EwS as SMN (approximately 1.1% of all patients) were reported, preceded by a heterogeneous group of malignancies, mainly acute lymphoblastic leukemias (n = 7) and lymphomas (n = 7). Three cases of EwS as SMN occurred in the presumed radiation field of the primary tumor. The median age at diagnosis of EwS as SMN was 19.4 years (range, 5.9-72) compared with 10.8 years (range, 0.9-51.2) for primary EwS. The median interval between first malignancy and EwS diagnosis was 7.4 years. The 3-year overall survival (OS)/event-free survival (EFS) was 0.69 (SE = 0.09)/0.53 (SE = 0.10) for localized patients and 0.36 (SE = 0.13)/0.29 (SE = 0.12) for metastatic patients (OS: p = 0.02; EFS: p = 0.03). Survival in patients with EwS as SMN did not differ between hematologic or solid primary malignancies. EwS as SMN is rare; however, survival is similar to that of primary EwS, and its risk-adjusted treatment should be curative, especially in localized patients.

Relevance of Abnormal KCNN1 Expression and Osmotic Hypersensitivity in Ewing Sarcoma.

Ewing sarcoma (EwS) is a rare and highly malignant bone tumor occurring mainly in childhood and adolescence. Physiologically, the bone is a central hub for Ca2+ homeostasis, which is severely disturbed by osteolytic processes in EwS. Therefore, we aimed to investigate how ion transport proteins involved in Ca2+ homeostasis affect EwS pathophysiology. We characterized the expression of 22 candidate genes of Ca2+-permeable or Ca2+-regulated ion channels in three EwS cell lines and found the Ca2+-activated K+ channel KCa2.1 (KCNN1) to be exceptionally highly expressed. We revealed that KCNN1 expression is directly regulated by the disease-driving oncoprotein EWSR1-FL1. Due to its consistent overexpression in EwS, KCNN1 mRNA could be a prognostic marker in EwS. In a large cohort of EwS patients, however, KCNN1 mRNA quantity does not correlate with clinical parameters. Several functional studies including patch clamp electrophysiology revealed no evidence for KCa2.1 function in EwS cells. Thus, elevated KCNN1 expression is not translated to KCa2.1 channel activity in EwS cells. However, we found that the low K+ conductance of EwS cells renders them susceptible to hypoosmotic solutions. The absence of a relevant K+ conductance in EwS thereby provides an opportunity for hypoosmotic therapy that can be exploited during tumor surgery.

Secondary malignant neoplasms after bone and soft tissue sarcomas in children, adolescents, and young adults.

BACKGROUND: Increased survival in young sarcoma patients comes along with a higher incidence of second malignant neoplasms (SMNs). The incidence, latency, histiotype, and outcome of these patients were analyzed because this information is essential to design evidence-based long-term follow-up care programs for young sarcoma survivors. METHODS: Patients entered on clinical trials or registered in registries with a primary sarcoma in 1 of the cooperative sarcoma study groups in the framework of the Society for Pediatric Oncology and Hematology (GPOH) were screened for SMNs. Descriptive analysis, the Kaplan-Meier method, the Gray model, the Fine-Gray model, and the Cox regression model were used for the statistical analyses. RESULTS: A total of 159 out of 7079 (2.2%) patients were registered with a SMN. Among them, 104 solid SMNs (65%) and 56 hematologic SMNs (35%) occurred. Median latency from first diagnosis of sarcoma to the diagnosis of SMN was 6.8 years (range, 0-26.7 years). Cumulative incidence of SMN was 8.8% after 30 years. Five-year-survival was 67.1% (95% confidence interval [CI], 66.0-68.2) for the 7079 patients and it was 45.1% (95% CI, 36.2-53.6) after the diagnosis of a SMN (subcohort of n = 159 patients). CONCLUSIONS: There is a remarkable high cumulative incidence of SMNs after bone and soft tissue sarcomas in children, adolescents, and young adults. Therefore, effective transition as well as risk adapted long-term follow-up care programs should be developed and offered to young sarcoma survivors. LAY SUMMARY: Bone sarcomas and soft tissue tumors are rare tumors in children, adolescents, and young adults. The treatment varies, but may comprise chemotherapy, surgery, and/or radiotherapy. Developing a subsequent malignant tumor is a long-term risk for the patients. To better characterize this risk, we analyzed the data of 7079 patients (up to 21 years old) with bone sarcomas or soft tissue tumors. Our findings provide a basis to counsel young sarcoma survivors on their individual risk of subsequent malignant tumors. Moreover, these data can help to establish recommendations for aftercare in young sarcoma survivors.

Gene expression and immunohistochemical analyses identify SOX2 as major risk factor for overall survival and relapse in Ewing sarcoma patients.

BACKGROUND: Up to 30-40% of Ewing sarcoma (EwS) patients with non-metastatic disease develop local or metastatic relapse within a time span of 2-10 years. This is in part caused by the absence of prognostic biomarkers that can identify high-risk patients and thus assign them to risk-adapted monitoring and treatment regimens. Since cancer stemness has been associated with tumour relapse and poor patient outcomes, we investigated in the current study the prognostic potential SOX2 (sex determining region Y box 2) - a major transcription factor involved in development and stemness - which was previously described to contribute to the undifferentiated phenotype of EwS. METHODS: Two independent patient cohorts, one consisting of 189 retrospectively collected EwS tumours with corresponding mRNA expression data (test-cohort) and the other consisting of 141 prospectively collected formalin-fixed and paraffin-embedded resected tumours (validation and cohort), were employed to analyse SOX2 expression levels through DNA microarrays or immunohistochemistry, respectively, and to compare them with clinical parameters and patient outcomes. Two methods were employed to test the validity of the results at both the mRNA and protein levels. FINDINGS: Both cohorts showed that only a subset of EwS patients (16-20%) expressed high SOX2 mRNA or protein levels, which significantly correlated with poor overall survival. Multivariate analyses of our validation-cohort revealed that high SOX2 expression represents a major risk-factor for poor survival (HR = 3·19; 95%CI 1·74-5·84; p < 0·01) that is independent from metastasis and other known clinical risk-factors at the time of diagnosis. Univariate analyses demonstrated that SOX2-high expression was correlated with tumour relapse (p = 0·002). The median first relapse was at 14·7 months (range: 3·5-180·7). INTERPRETATION: High SOX2 expression constitutes an independent prognostic biomarker for EwS patients with poor outcomes. This may help to identify patients with localised disease who are at high risk for tumour relapse within the first two years after diagnosis. FUNDING: The laboratory of T. G. P. Grünewald is supported by grants from the 'Verein zur Förderung von Wissenschaft und Forschung an der Medizinischen Fakultät der LMU München (WiFoMed)', by LMU Munich's Institutional Strategy LMUexcellent within the framework of the German Excellence Initiative, the 'Mehr LEBEN für krebskranke Kinder - Bettina-Bräu-Stiftung', the Walter Schulz Foundation, the Wilhelm Sander-Foundation (2016.167.1), the Friedrich-Baur foundation, the Matthias-Lackas foundation, the Barbara & Hubertus Trettner foundation, the Dr. Leopold & Carmen Ellinger foundation, the Gert & Susanna Mayer foundation, the Deutsche Forschungsgemeinschaft (DFG 391665916), and by the German Cancer Aid (DKH-111886 and DKH-70112257). J. Li was supported by a scholarship of the China Scholarship Council (CSC), J. Musa was supported by a scholarship of the Kind-Philipp foundation, and T. L. B. Hölting by a scholarship of the German Cancer Aid. M. F. Orth and M. M. L. Knott were supported by scholarships of the German National Academic Foundation. G. Sannino was supported by a scholarship from the Fritz-Thyssen Foundation (FTF-40.15.0.030MN). The work of U. Dirksen is supported by grants from the German Cancer Aid (DKH-108128, DKH-70112018, and DKH-70113419), the ERA-Net-TRANSCAN consortium (project number 01KT1310), and Euro Ewing Consortium (EEC, project number EU-FP7 602,856), both funded under the European Commission Seventh Framework Program FP7-HEALTH (http://cordis.europa.eu/), the Barbara & Hubertus Trettner foundation, and the Gert & Susanna Mayer foundation. G. Hardiman was supported by grants from the National Science Foundation (SC EPSCoR) and National Institutes of Health (U01-DA045300). The laboratory of J. Alonso was supported by Instituto de Salud Carlos III (PI12/00816; PI16CIII/00026); Asociación Pablo Ugarte (TPY-M 1149/13; TRPV 205/18), ASION (TVP 141/17), Fundación Sonrisa de Alex & Todos somos Iván (TVP 1324/15).

Impact of Whole Lung Irradiation on Survival Outcome in Patients With Lung Relapsed Ewing Sarcoma.

PURPOSE: There is no standard treatment procedure for relapsed Ewing sarcoma (EwS). This retrospective analysis evaluates the survival outcome in patients with an isolated pulmonary relapse of EwS treated with whole lung irradiation (WLI) in addition to second line chemotherapy (Ctx). METHODS AND MATERIALS: In our study, 136 patients with pulmonary relapsed EwS who were registered in the relapse register of the Cooperative Ewing Sarcoma Study group or the Sarcoma Relapse Registry for relapsed sarcoma of bone and soft tissues were analyzed. All patients received relapse Ctx or an additional total resection of lung metastasis. Of these patients, 88 (median age, 21 years; range, 7-52 years) achieved a second remission by the relapse treatment. Of these 88 patients, 48 patients received an additional WLI. The 3-year progression-free survival (PFS) and 3-year overall survival (OS) were analyzed (median follow-up, 3 years; range, 7 months to 11 years and 9 months). Additional prognostic factors for survival outcomes, including the response of lung metastases to Ctx, were also estimated. RESULTS: The survival outcome was significantly improved after WLI when analyzing the entire group of pulmonary relapsed patients: 3-year PFS 36% (+WLI) versus 14% (-WLI) (P = .001); 3- year OS 47% (+WLI) versus 33% (-WLI) (P = .007). The 3-year PFS in patients with complete remission of lung relapse receiving WLI (n = 48) compared with those without WLI (n = 40), was 37% (+WLI) versus 21% (-WLI) (P = .18). The site of the primary tumor and the response of pulmonary lesions to Ctx were significant prognostic indicators for survival in patients treated with WLI. No severe pulmonary function disorders or lung toxicities were observed after WLI treatment in both pediatric and adult patients. CONCLUSIONS: The WLI does not correlate with improved OS in patients with pulmonary relapsed EwS. However, a marginal trend toward superior PFS and improved local control of pulmonary disease suggests the application of WLI in patients with EwS with isolated lung relapse and second clinical remission.

Array-based DNA-methylation profiling in sarcomas with small blue round cell histology provides valuable diagnostic information.

Undifferentiated solid tumors with small blue round cell histology and expression of CD99 mostly resemble Ewing sarcoma. However, they also may include other tumors such as mesenchymal chondrosarcoma, synovial sarcoma, or small cell osteosarcoma. Definitive classification usually requires detection of entity-specific mutations. While this approach identifies the majority of Ewing sarcomas, a subset of lesions remains unclassified and, therefore, has been termed "Ewing-like sarcomas" or small blue round cell tumors not otherwise specified. We developed an approach for further characterization of small blue round cell tumors not otherwise specified using an array-based DNA-methylation profiling approach. Data were analyzed by unsupervised clustering and t-distributed stochastic neighbor embedding analysis and compared with a reference methylation data set of 460 well-characterized prototypical sarcomas encompassing 18 subtypes. Verification was performed by additional FISH analyses, RNA sequencing from formalin-fixed paraffin-embedded material or immunohistochemical marker analyses. In a cohort of more than 1,000 tumors assumed to represent Ewing sarcomas, 30 failed to exhibit the typical EWS translocation. These tumors were subjected to methylation profiling and could be assigned to Ewing sarcoma in 14 (47%), to small blue round cell tumors with CIC alteration in 6 (20%), to small blue round cell tumors with BCOR alteration in 4 (13%), to synovial sarcoma and to malignant rhabdoid tumor in 2 cases each. One single case each was allotted to mesenchymal chondrosarcoma and adamantinoma. 12/14 tumors classified as Ewing sarcoma could be verified by demonstrating either a canonical EWS translocation evading initial testing, by identifying rare breakpoints or fusion partners. The methylation-based assignment of the remaining small blue round cell tumors not otherwise specified also could be verified by entity-specific molecular alterations in 13/16 cases. In conclusion, array-based DNA-methylation analysis of undifferentiated tumors with small blue round cell histology is a powerful tool for precisely classifying this diagnostically challenging tumor group.

Ewing sarcoma partial regression without GvHD by chondromodulin-I/HLA-A*02:01-specific allorestricted T cell receptor transgenic T cells.

Background: Chondromodulin-I (CHM1) sustains malignancy in Ewing sarcoma (ES). Refractory ES carries a dismal prognosis and patients with bone marrow (BM) metastases do not survive irrespective of therapy. We assessed HLA-A*02:01/CHM1-specific allorestricted T cell receptor (TCR) wild-type and transgenic cytotoxic (CD8+) T cells against ES. Patients and Methods: Three refractory HLA-A2+ ES patients were treated with HLA-A*02:01/peptide-specific allorepertoire-derived (i.e., allorestricted) CD8+ T cells. Patient #1 received up to 4.8 × 105/kg body weight HLA-A*02:01- allorestricted donor-derived wild-type CD8+ T cells. Patient #2 received up to 8.2 × 106/kg HLA-A*02:01- donor-derived and patient #3 up to 6 × 106/kg autologous allorestricted TCR transgenic CD8+ T cells. All patients were treated with the same TCR complementary determining region 3 allorecognition sequence for CHM1 peptide 319 (CHM1319). Results: HLA-A*02:01/CHM1319-specific allorestricted CD8+ T cells showed specific in vitro lysis of all patient-derived ES cell lines. Therapy was well tolerated and did not cause graft versus host disease (GvHD). Patients #1 and #3 showed slow progression, whereas patient #2, while having BM involvement, showed partial metastatic regression associated with T cell homing to involved lesions. CHM1319 TCR transgenic T cells could be tracked in his BM for weeks. Conclusions: CHM1319-TCR transgenic T cells home to affected BM and may cause partial disease regression. HLA-A*02:01/antigen-specific allorestricted T cells proliferate in vivo without causing GvHD.

The value of high-dose chemotherapy in patients with first relapsed Ewing sarcoma.

BACKGROUND: Prognosis of patients with relapsed Ewing sarcoma (ES) is poor. The 5-year overall survival (OS) is 13%. We analyzed high-dose chemotherapy (HDtx) versus conventional chemotherapy (CHtx) in patients with relapsed ES. PROCEDURE: Data from 239 patients with first relapse, registered during 2000-2011 in the ES relapse registry of the Cooperative Ewing Sarcoma Study Group (CESS) were analyzed. RESULTS: Of 239 patients, 200 received various non-HDtx second-line CHtx regimens. Seventy-three patients had additional HDtx followed by autologous stem cell rescue. The 2-year event-free survival (EFS) was 10% (SE = 0.02) in patients treated without HDtx and 45% (SE = 0.09) in patients treated with HDtx. In a second step, we focused on those patients who achieved complete remission (CR) or partial remission (PR) after four to six cycles of conventional second-line CHtx. Here, the 2-year EFS was 31% (SE = 0.08) without additional HDtx and 44% (SE = 0.09) with additional HDtx. In addition, multivariate regression analysis indicates absence of HDtx treatment, with a Hazard ratio (HR) of 2.90 (95% CI 1.41-6.0), and early relapse, with a HR of 4.76 (95% CI 2.31-9.78), as independent prognostic factors for EFS. CONCLUSION: Additional HDtx may contribute to further reduce the risk of further events in patients who respond to conventional second-line CHtx.