Impact of first-line treatment on outcomes of Ewing sarcoma of the spine.

The optimal first-line treatment for primary Ewing sarcoma (ES) of the spine is unclear, especially when the patients present with acute neurological deficits. This study aimed to retrospectively analyze the effect of first-line treatment with surgery or chemotherapy on neurological and survival outcomes of ES of the spine. 39 patients treated between January 2005 and December 2016 were included in the present analysis. 29 (74.4%) presented with symptomatic spinal cord compression at diagnosis. 21 patients were submitted to primary surgery followed by chemotherapy and local radiotherapy, while 18 patients received induction chemotherapy before surgery and/or local radiotherapy. Neurological deficit before and after treatment, event-free survival and overall survival were analyzed. The results indicated that chemotherapy as the first-line treatment could achieve similar results as primary surgery in preserving neurological function, even in case of major neurological deficits. Compared with primary surgery, induction chemotherapy contributed to a higher rate of en bloc resection with a microscopic negative margin (R0) of primary tumor (72.7% vs. 28.6%, P < 0.05). Multivariate Cox regression analyses revealed that initial chemotherapy was a favorable independent prognostic factor of event-free survival (hazard ratio, 0.215; 95% confidence interval, 0.077-0.596; P = 0.003) and overall survival (hazard ratio, 0.288, 95% confidence interval, 0.098-0.852; P = 0.024). In conclusion, our study suggests that first-line treatment of ES of the spine should be induction chemotherapy, even in case of major neurological deficits.