Localized Ewing's Sarcoma Of Bone Research Articles

Histological response to neoadjuvant chemotherapy in localized Ewing sarcoma of the bone: A retrospective analysis of available scoring tools

AimThe aim is to evaluate which of the existing scoring systems of histological response to neoadjuvant chemotherapy best stratifies the clinical outcome of patients with localized Ewing sarcoma of bone. Methods474 patients with diagnosis of localized Ewing sarcoma of bone were included. The median follow-up was 13.5 years. ResultsThe overall survival and the disease-free survival (DFS) were 70.8% and 63.9% at 5 years. The percentage of histological response to neoadjuvant chemotherapy ranged between 5% and 100% (mean 83%). The agreement between Bologna System and the different percentual cut-offs of histological response to neoadjuvant chemotherapy was high, with kappa statistics of 0.83 for a cut-off of ≥90%; 0.86 for a cut-off of ≥95%; 0.79 for a cut-off of ≥96% and 0.61 for a cut-off of 100%. Statistically higher DFS rates for good responders compared to poor responders were found when using each given system. Model performance indicators showed that Bologna system had a lower AIC score and a higher c-statistics to predict DFS. When the patients classified as good responders using the different percentual cut-offs of histological response to neoadjuvant chemotherapy, were instead re-classified using the Bologna system, statistical differences were noted in DFS within each specific group. ConclusionsAll scoring tools to evaluate histological response to neoadjuvant chemotherapy offer good predictive value for DFS in localized Ewing’s sarcoma of bone. The Bologna system better stratifies those patients with histological response to neoadjuvant chemotherapy between 90 and 99%, representing a more reliable scoring tool in this subset.

Maximum tumor dimension and tumor volume as prognostic factors in patients with newly diagnosed localized Ewing sarcoma (ES)- a report from the Children’s Oncology Group (COG).

11529 Background: Maximum tumor dimension > 8 cm. and large tumor volume have been reported to be adverse prognostic factors in patients with ES but have not been prospectively evaluated in the context of a phase 3 clinical trial with interval compressed chemotherapy. Methods: COG AEWS1031 (NCT01231906) was a randomized phase 3 clinical trial comparing interval compressed chemotherapy regimens in patients with newly diagnosed localized ES of bone and soft tissue. A correlative objective of AEWS1031 was to evaluate tumor size and volume as prognostic factors. Institution-reported dimensions of the primary tumor from baseline imaging were prospectively collected. For inclusion in this analysis, patients had to have at least 1 tumor dimension reported for tumor size analyses and dimensions in 3 axes for tumor volume analyses. Maximum dimension was dichotomized as less than vs. > / = 8cm. Tumor volume was dichotomized as less than vs. > / = 200 mL. Event-free (EFS) and overall survival (OS) from enrollment were calculated using Kaplan-Meier methods and compared between groups using a two-sided log-rank test. Hazard ratios (HR) and confidence intervals (CI) were calculated using the Cox model. Results: The 5-year EFS and OS of the 629 eligible patients was 78% (95% CI: 75-81%) and 87% (95% CI: 84-90%) respectively and there was no significant difference in both EFS and OS between the randomized interval compressed chemotherapy arms of AEWS1031. 590 of 629 (94%) patients were evaluable for maximum tumor dimension and 307 (52%) had tumors > / = 8 cm. Patients with tumors > / = 8 cm were at significantly increased risk for EFS events (p = 0.016) with estimated 5-year EFS of 73.7% (95% CI: 68.1 vs.78.4%) vs. 82.9% (95% CI 77.7-87.1%) for patients with tumors < 8 cm [HR: 1.53 (1.08-2.17)]. For tumor volume, 586 of 629 patients (93%) were evaluable and 180 (31%) had tumors > / = 200 mL. Patients with tumor volume > / = 200 mL were at significantly increased risk for EFS events (p = 0.003) with estimated 5-year EFS of 70% (95% CI: 62.3-76.4%) vs. 81.6% (95% CI: 77.2-85.2%) for patients with tumors < 200 mL [HR: 1.69 (1.2-2.39)]. Conclusions: Maximum tumor dimension and tumor volume as defined are both prognostic in patients with newly diagnosed localized ES treated with interval compressed chemotherapy. Clinical trial information: NCT01231906 .

Comparative evaluation of local control strategies in localized Ewing sarcoma of bone: a report from the Children's Oncology Group.

Patients with Ewing sarcoma require local primary tumor control with surgery, radiation, or both. The optimal choice of local control for overall and local disease control remains unclear. Patients with localized Ewing sarcoma of bone who were treated on 3 consecutive protocols with standard-dose, 5-drug chemotherapy every 3 weeks were included (n=465). Propensity scores were used to control for differences between local control groups by constructing multivariate models to assess the impact of local control type on clinical endpoints (event-free survival [EFS], overall survival, local failure, and distant failure) independent of differences in their propensity to receive each local control type. Patients who underwent surgery were younger (P=.02) and had more appendicular tumors (P<.001). Compared with surgery, radiation had higher unadjusted risks of any event (hazard ratio [HR], 1.70; 95% confidence interval [CI], 1.18-2.44), death (HR, 1.84; 95% CI, 1.18-2.85), and local failure (HR, 2.57; 95% CI, 1.37-4.83). On multivariate analysis, compared with surgery, radiation had a higher risk of local failure (HR, 2.41; 95% CI, 1.24-4.68), although there were no significant differences in EFS (HR, 1.42; 95% CI, 0.94-2.14), overall survival (HR, 1.37; 95% CI, 0.83-2.26), or distant failure (HR, 1.13; 95% CI, 0.70-1.84) between local control groups. In this large group of similarly treated patients, choice of the mode of local control was not related significantly to EFS, overall survival, or distant failure, although the risk of local failure was greater for radiation compared with surgery. These data support surgical resection when appropriate, whereas radiotherapy remains a reasonable alternative in selected patients.

Evaluation of local control strategies in patients with localized Ewing sarcoma of bone: A report from the Children’s Oncology Group.

9537 Background: Patients (pts) with Ewing sarcoma (EWS) require local control, either with surgery alone (S), radiation alone (R), or a combination of surgery + radiation (S+R). Optimal choice of local control for disease control remains unclear. Our primary aim was to determine the mode of local control associated with the highest event-free survival (EFS). Methods: Pts with localized EWS of bone treated on INT0091, INT0154, or AEWS0031 phase III trials were included if they had complete local control data, did not have cranial tumors, received local control starting 2-6 months after enrollment, and were randomized to receive standard dose 5-drug chemotherapy every 3 weeks. We used propensity scores to control for differences in age, tumor site, and year of diagnosis between local control groups. We constructed Cox models controlling for local control propensity scores to assess the impact of local control type on EFS and overall survival (OS) from the start of local control. Results: 465 pts were included. Pts selected for S were treated more recently (p &lt; 0.001), more likely to have appendicular tumors (p &lt; 0.001), and younger (p = 0.02). Pts treated with R, compared to S, had higher unadjusted risk of any event (HR 1.70; 95% CI 1.18 - 2.44; p = 0.004) or death (HR 1.84; 95% CI 1.18 – 2.85; p = 0.006). Pts treated with S+R, compared to S, had higher unadjusted risk of death (HR 1.75; 95% CI 1.10 – 2.76; p = 0.02). After adjusting for propensity scores, there was a trend of higher risk of any event for pts treated with R (HR 1.42; 95% CI 0.94 – 2.14; p = 0.10) compared to S, though this was not statistically significant. No other differences in adjusted risk of event or death between local control groups were statistically significant. We confirmed these results with standard Cox models using age, tumor site, and year of diagnosis as covariates. Conclusions: In this large group of uniformly treated pts, investigator choice of local control approach was not significantly related to EFS. These data support current practice of surgical resection when feasible, while validating radiotherapy as a reasonable alternative in selected pts.

Rosito P, Mancini AF, Rondelli R, et al. Italian cooperative study for the treatment of children and young adults with localized Ewing sarcoma of bone: a preliminary report of 6 years of experience. Cancer. (1999) 86(3)421–8.

AbstractThe original article to which this Erratum refers was published in Cancer ( 1999) 86(3) 421–8

Ewing sarcoma: radiation dose and target volume.

The outcome of children and adolescents with Ewing sarcoma is impacted by many prognostic factors and often measured by estimates of: event-free, relapse-free, disease-free, or overall survival. However, the preferred assessment following radiation therapy is local control. A review of large group experiences over the past several decades was undertaken to assess the optimal radiation dose and volume for patients with localized, osseous Ewing sarcoma. New approaches and techniques to improve local control were also investigated. With multidisciplinary therapy, 5-year overall local control rates range from 58 to 93%. Following definitive irradiation, they are 53-86%. Recommended radiation therapy doses are 55.8-60.0 Gy. In the postoperative setting, gross disease requires 55.8 Gy; microscopic disease requires 45 Gy. Altered fractionation schemes have not improved local control. The appropriate irradiated volume is an involved field to the pretreatment tumor volume plus 2.0-2.5 cm margin, followed by a boost to the post-induction chemotherapy tumor volume with margin. Good radiation quality control with central review improves local control. Use of an involved radiation field requires accuracy in defining tumor volume. Techniques to improve local control include risk-adapted multidisciplinary therapy, intraoperative boost radiation, and high radiation doses as delivered by 3-dimensional conformal radiation. Intensity modulated and proton beam radiotherapy may offer an advantage at special sites. Innovative uses of radiation in the multidisciplinary setting will continue to provide excellent local control, improved function, and quality of life for young patients with localized Ewing sarcoma of bone.