S100A7A and histiocytic sarcoma: The ROC curve analysis of the relationship between the serum concentration of S100A15 in the individuals with HS in Hurley stage III and in the individuals with HS in the less severe stages (Hurley I and Hurley II) revealed an AUC of 0.88 (95%CI for AUC: 0.77–0.99) (p < 0.0001).