Ewing sarcoma in adults treated with modern radiotherapy techniques

Current approaches to management of bone sarcoma in adolescent and young adult patients

Bone tumors are a group of histologically diverse diseases that occur across all ages. Two of the commonest, osteosarcoma (OS) and Ewing sarcoma (ES), are regarded as characteristic adolescent and young adult (AYA) cancers with an incidence peak in AYAs. They are curable for some but associated with unacceptably high rates of treatment failure and morbidity. The introduction of effective new therapeutics for bone sarcomas is slow, and to date, complex biology has been insufficiently characterized to allow more rapid therapeutic exploitation. This review focuses on current standards of care, recent advances that have or may soon change that standard of care and challenges to the expert clinical research community that we suggest must be met.

Childhood Cancer: Occurrence, Treatment and Risk of Second Primary Malignancies

Cancer represents the leading cause of disease-related death and treatment-associated morbidity in children with an increasing trend in recent decades worldwide. Nevertheless, the 5-year survival of childhood cancer patients has been raised impressively to more than 80% during the past decades, primarily attributed to improved diagnostic technologies and multiagent cytotoxic regimens. This strong benefit of more efficient tumor control and prolonged survival is compromised by an increased risk of adverse and fatal late sequelae. Long-term survivors of pediatric tumors are at the utmost risk for non-carcinogenic late effects such as cardiomyopathies, neurotoxicity, or pneumopathies, as well as the development of secondary primary malignancies as the most detrimental consequence of genotoxic chemo- and radiotherapy. Promising approaches to reducing the risk of adverse late effects in childhood cancer survivors include high precision irradiation techniques like proton radiotherapy or non-genotoxic targeted therapies and immune-based treatments. However, to date, these therapies are rarely used to treat pediatric cancer patients and survival rates, as well as incidences of late effects, have changed little over the past two decades in this population. Here we provide an overview of the epidemiology and etiology of childhood cancers, current developments for their treatment, and therapy-related adverse late health consequences with a special focus on second primary malignancies.

Impact of chemotherapy cycles and intervals on outcomes of nonspinal Ewing sarcoma in adults: a real-world experience

BACKGROUND

Adult Ewing sarcoma (ES) is a rare disease, the optimal treatment model is unknown. This study aimed to retrospectively analyze treatment-related prognostic factors of nonspinal ES in Chinese adults.

METHODS

Eighty-one patients treated between January 2005 and December 2017 were included in the present study. Thirty-three (40.7%) presented with metastatic disease at diagnosis. Eight patients were submitted to primary surgery followed by chemotherapy, while 73 patients received chemotherapy before and after surgery and/or local radiotherapy. The chemotherapy regimen included 8-17 cycles of vincristine, doxorubicin, and cyclophosphamide (VDC) alternating with ifosfamide and etoposide (IE) every 3 weeks. Clinical outcomes and safety were analyzed.

RESULTS

VDC/IE chemotherapy was well tolerated in adult patients with ES. Multivariate Cox regression analyses revealed that chemotherapy of at least 12 cycles was a favorable independent prognostic factor of event-free survival (hazard ratio, 0.558; 95% confidence interval, 0.323-0.965; P = 0.037) and overall survival (hazard ratio, 0.424; 95% confidence interval, 0.240-0.748; P = 0.003). Similarly, a low frequency of chemotherapy delays was an independent prognostic factor of improved OS (hazard ratio, 0.438; 95% confidence interval, 0.217-0.887; P = 0.022).

CONCLUSION

Our study suggests that adults with ES should be treated with an aggressive multidisciplinary approach, intensive chemotherapy with adequate cycles and appropriate intervals can be recommended in this group.

Extraskeletal Ewing's sarcoma/peripheral primitive neuroectodermal tumor of the small bowel presenting with gastrointestinal perforation

Extraskeletal Ewing’s sarcoma (E-EWS)/peripheral primitive neuroectodermal tumor (pPNET) is a rare soft tissue tumor that arises from a multipotent progenitor cell and is considered to be of neuroectodermal origin. Although soft tissue E-EWS/pPNETs are common, they are exceedingly rare in the small bowel. Only 30 cases of E-EWS/pPNET of the small bowel have been reported. However, only one case of gastrointestinal perforation has been reported till today. Here, we report the second case of E- EWS/pPNET with gastrointestinal perforation.

Comparison of the effects of local treatment strategies in non-metastatic Ewing sarcoma of bone

BACKGROUND

To investigate the optimal local treatment strategies for patients with non-metastatic Ewing sarcoma (ES) of bone.

METHODS

Patients with ES of bone were identified using the Surveillance Epidemiology and End Results database. Kaplan-Meier log-rank test and Cox regression models were performed to assess the effect of the types of local treatment strategies on cause-specific survival and overall survival.

RESULTS

560 patients were included with a median age of 16 years. A total of 284, 162 and 114 patients received surgery alone, surgery and radiotherapy, and radiotherapy alone, respectively. The types of local treatment strategies had no effect on survival outcomes in multivariate analysis. In the subgroup analysis of patients with tumor diameter <8 cm, surgery ± radiotherapy had a significantly improved cause-specific survival (P = 0.039), and had potential to improve overall survival (P = 0.070) in multivariate analysis. The local treatment strategies had no effect on survival in patients with different tumor location.

CONCLUSION

There is no local treatment of choice for non-metastatic ES of bone in terms of survival. More well-designed studies are needed to confirm our findings and investigate the role of various local treatment strategies in relation to primary tumor diameter.

Identification of Patients With Localized Ewing Sarcoma at Higher Risk for Local Failure: A Report From the Children's Oncology Group

PURPOSE

To identify clinical and treatment variables associated with a higher risk of local failure in Ewing sarcoma patients treated on recent Children's Oncology Group protocols.

METHODS AND MATERIALS

Data for 956 patients treated with ifosfamide and etoposide-based chemotherapy on INT-0091, INT-0154, and AEWS0031 were analyzed. Local treatment modalities were defined as surgery, definitive radiation therapy (RT), or surgery plus radiation (S+RT). Five-year cumulative incidence of local failure was determined.

RESULTS

The local failure rate for the entire cohort was 7.3%, with a 3.9% rate for surgery, 15.3% for RT (P<.01), and 6.6% for S+RT (P=.12). The local failure incidence was 5.4% for extremity tumors, 13.2% for pelvis tumors (P<.01), 5.3% for axial non-spine tumors (P=.90), 9.1% for extraskeletal tumors (P=.08), and 3.6% for spine tumors (P=.49). The incidence of local failure was 14.8% for extremity tumors and 22.4% for pelvis tumors treated with RT, compared with 3.7% for extremity tumors and 3.9% for pelvis tumors treated with surgery (P≤.01). There was no difference in local failure incidence by local treatment modality for axial non-spine, spine, and extraskeletal tumors. The local failure incidence was 11.9% in patients aged ≥18 years versus 6.7% in patients aged <18 years (P=.02). Age ≥18 years (hazard ratio 1.9, P=.04) and treatment with RT (hazard ratio 2.40, P<.01) remained independent prognostic factors for higher local failure incidence on multivariate analysis. Tumor size (</≥ 8 cm) was available in 40% of patients and did not correlate with local failure incidence.

CONCLUSIONS

Local tumor control is excellent and similar between surgery and RT for axial non-spine, spine, and extraskeletal tumors. Age ≥18 years and use of RT, primarily for pelvis and extremity tumors, are associated with the highest risk of local failure. Further efforts should focus on improving outcomes for these patients.

Systemic Therapy Outcomes in Adult Patients with Ewing Sarcoma Family of Tumors

Background

The Ewing sarcoma family of tumors (ESFT) is a rare but curable bone neoplastic entity. The current standard of care involves chemotherapy and local disease control with surgery or radiation regardless of the extent of disease at presentation. Data that document the effectiveness of the current approach in the adult patient population are limited.

Methods

We performed a retrospective review including all ESFT patients older than 19 years of age who received systemic therapy between January 2002 and December 2013 at our institution. The main study outcome was overall survival; secondary outcomes were objective response rate, disease-free survival, and progression-free survival.

Results

Eighteen patients with ESFT were identified. The median overall survival for the entire group was 20.65 months (range 0.43–114.54). In patients with localized disease, the 1-, 2-, and 3-year survival rates were 90, 80, and 70%, respectively. Age was not correlated with overall survival (r = 0.58, p = 0.76). The 3-year disease-free survival rate was 70%. In patients with metastatic disease, the 1-year survival rate was 40%. In patients treated in the neoadjuvant and palliative setting with chemotherapy, we observed an objective response rate of 61.54%. The time to progression in patients with metastatic disease treated with chemotherapy ranged from 0.69 to 4.93 months.

Conclusion

In this group of adult patients with ESFT treated with multimodality therapy, the outcomes were similar to those reported in well-known larger clinical trials that typically included younger patients. Age was not associated with worse survival.

A Therapeutic Role for Survivin in Mitigating the Harmful Effects of Ionizing Radiation

Background. Radiation therapy is a form of adjuvant care used in many oncological treatment protocols. However, nonmalignant neighboring tissues are harmed as a result of this treatment. Therefore, the goal of this study was to induce the production of survivin, an antiapoptotic protein, to determine if this protein could provide protection to noncancerous cells during radiation exposure. Methods. Using a murine model, a recombinant adenoassociated virus (rAAV) was used to deliver survivin to the treatment group and yellow fluorescence protein (YFP) to the control group. Both groups received targeted radiation. Visual inspection, gait analysis, and tissue histology were used to determine the extent of damage caused by the radiation. Results. The YFP group demonstrated ulceration of the irradiated area while the survivin treated mice exhibited only hair loss. Histology showed that the YFP treated mice experienced dermal thickening, as well as an increase in collagen that was not present in the survivin treated mice. Gait analysis demonstrated a difference between the two groups, with the YFP mice averaging a lower speed. Conclusions. The use of gene-modification to induce survivin expression in normal tissues allows for the protection of nontarget areas from the negative side effects normally associated with ionizing radiation.

The role of radiotherapy in local control of nonextremity Ewing sarcomas

PURPOSE

To evaluate the results of radiotherapy and the prognostic factors affecting local control in nonextremity Ewing sarcomas.

METHODS

Between 1995 and 2011, 44 patients with nonextremity Ewing sarcomas were treated with radiotherapy. Tumor localizations were pelvis in 23, spine in 13, thoracic region in 5, and cranium in 3 patients. Tumor size was ≥8 cm in 56.8% of patients. Distant metastases were present in 19 of the patients at the time of diagnosis (43.1%). All patients were treated with 12 weeks of neoadjuvant chemotherapy followed by surgery and radiotherapy (45-54 Gy) or radiotherapy alone (54-64.8 Gy). Radiotherapy was applied due to microscopic residue (R1) in 5 patients after the operation and macroscopic tumor in 39 patients (macroscopic residue [R2] and nonresectable tumor).

RESULTS

Median follow-up was 49 months (range 9-195). Local failures developed in 7 patients (15.9%) and local control at 5 years was 81.4%. Local recurrence was detected in 6 patients (6/38) who did not have residual tumor after RT. Progression was detected in 1 patient (1/6) who had residual tumor. All those patients with local failure experienced further distant metastases. Possible prognostic factors such as age (≤17 vs &gt;17), tumor localization, tumor volume (≤8 cm vs &gt;8 cm), and M status at diagnosis (0 vs 1) were not related to local control.

CONCLUSIONS

Radiotherapy, either alone or adjuvant to surgery, provides local control in 80% of nonextremity Ewing sarcomas and plays an important role in treatment.