Multimodality treatment of intradural extramedullary Ewing's sarcomas. A systematic review

Ewing's sarcoma (ES) is an aggressive bone and soft tissue sarcoma that usually affects adolescents and young adults. ES occasionally presents as an intradural-extramedullary lesion of the spine. Our aim was to study the role of the multimodality treatment on the survival (overall survival, recurrence-free survival, and metastasis-free survival) of patients with intradural-extramedullary Ewing's sarcoma. Pubmed, EMBASE, Scopus, Web of Science, Cochrane Reviews were searched up to January 2017, using as mesh terms "intradural extramedullary", "Ewing's sarcoma", AND "treatment". The multidisciplinary treatment was recorded in binary variables under the headings of "surgery", "chemotherapy" and "radiotherapy". We also recorded three time-to-event variables, including death, recurrence, and metastasis. We performed survival analysis for all potential combinations. Twenty articles with twenty-three patients were eligible for the current review. The survival curves of GTR did not differ from the equivalent of STR regarding survival (p=0.098), recurrence-free survival (p=0.318), and metastasis-free survival (p=0.089). Patients who received chemotherapy enjoyed longer survival regarding overall survival (p<0.05), recurrence-free survival (p<0.05), and metastasis-free survival (p<0.05), when compared to those who did not receive chemotherapy. Their overall survival of patients who had radiotherapy was marginally superior to those who did not receive (p=0.0653). However, their recurrence-free survival (p<0.05), and metastasis-free survival (p<0.05) were significantly improved in comparison to the latter. In conclusion, the multimodality treatment is mandatory for the management of patients with intradural extramedullary Ewing's sarcomas, with surgery assisting in the diagnosis and decompression the neural elements. However, it is chemotherapy that improves survival, recurrence-free survival, and metastasis-free survival. Radiotherapy is reserved as an adjuvant therapy in the local control, especially in cases with subtotal tumour resection.