The Prognostic Role of the C-Reactive Protein and Serum Lactate Dehydrogenase in a Pediatric Series of Bone Ewing Sarcoma

Background: Ewing sarcoma (ES) is a rare and aggressive pediatric cancer. Numerous studies have attempted to identify new prognostic biomarkers. The predictive value of serum LDH and CRP has not been clearly described, to date. Methods: The objective of our retrospective study was to investigate the prognostic value of LDH and CRP levels and their association with overall survival in a series of ES patients. Results: Between 2004 and 2019, 89 ES patients were included. In a univariable analysis, high levels of LDH and CRP were associated with the worst prognosis. In a multivariable analysis, only higher LDH values remained associated with a lower survival. The high-LDH-level group experienced all 21 deaths registered in our population (24%) and about 90% of disease progressions. The 5-year overall survival was 66.4% in the high-LDH-level group, while no deaths were observed in the low-LDH-level group. The 5-year progression-free survival was 57.9% in the high-LDH-level group versus 80.4% in the low-LDH-level group. Conclusions: In our study, LDH levels at diagnosis were strongly correlated with the prognosis, and they might be considered a prognostic factor in Ewing sarcoma. The LDH value, along with its very low cost and its reproducibility in almost all centers, make it suitable as a potential prognostic biomarker in clinical practice.