Seeking international consensus on approaches to primary tumour treatment in Ewing sarcoma

Abstract

Background The local treatment of Ewing sarcoma of bone involves surgery, radiotherapy or both. The selection of treatment depends on the anatomical extent of the tumour, the effectiveness of the proposed treatment, its morbidity, and the expectation of cure. However, not only are there variations in the approach to local treatment between individual patients, but also between treatment centres and countries. Our aim was to explore variation in practice and develop consensus statements about local treatment. Methods A three stage modified Delphi technique was used with international collaborators. This involved an expert panel to identify areas of controversy, an online survey of international collaborators and a consensus meeting in London, UK in June 2017. In the consensus meeting, teams of clinicians discussed the local management of selected cases and their responses were collected with electronic voting. Results Areas of greater or less consensus were identified. The lack of evidence underpinning different approaches was noted and areas for collaborative research became apparent. Conclusion This has demonstrated that there is an international consensus around many aspects of the local treatment of Ewing sarcoma of bone, including the use of specialist MultiDisciplinary Team (MDT) meetings with access to all appropriate treatments. However, considerable variation remains including the use of different staging investigations, decision making, definitions of response, and radiotherapy doses and timing. Further collaborative work should be undertaken to determine the impact of these variations in order to define best practice.

Ewing Sarcoma—Diagnosis, Treatment, Clinical Challenges and Future Perspectives

“…The radiological response to chemotherapy is important when considering local therapy options [ 17 ]. Follow-up care as part of trial protocols creates a survival advantage [ 37 ].…”

“…Open or CNB biopsy is recommended if EwS is suspected. Moreover, suspected solitary bone metastases as well as metastases in lymph nodes should be biopsied at presentation if possible [ 17 ].…”

“…Local therapy in patients with EwS is highly individualized. Patients should have the opportunity to explore local treatment options as soon after diagnosis as possible and decisions about local therapy should be made in collaboration with patients and families [ 17 ]. Expert interdisciplinary tumor boards are indispensable to define the optimal management in each individual case [ 99 ].…”

“…Implant-associated infections are clinically relevant as they may disrupt adjuvant chemotherapy or result in amputation [ 116 , 117 ]. Noteworthy, post-operative RT has a negative impact on non-oncologic outcomes, especially infection and prosthetic failure, after endoprosthetic replacement of a long bone [ 17 ].…”

“…The surgical margin status is a reliable indicator of tumor left in the patient [ 17 ]. An adequate surgical margin is one in which there is no viable tumor at the edge of the resection specimen that can be obtained by wide tumor resection, i.e., sufficient safety distance to the reactive zone of the tumor.…”