title: SERUM VALUES OF ALKALINE PHOSPHATASE AND LACTATE DEHYDROGENASE IN EWING'S SARCOMA.
abstract: OBJECTIVE
  To study the relationship between the serum levels of alkaline phosphatase (AP) and lactate dehydrogenase (LDH), and the percentage of tumor necrosis (TN) in patients with Ewing´s Sarcoma (ES).
  
  
  METHODS
  This is a case series with retrospective evaluation of patients with diagnosis of ES divided into 2 groups: Group 1, patients whose serum levels of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were obtained in the staging phase before preoperative chemotherapy (CT), and Group 2, patients whose values were measured after completion of the preoperative CT. The percentage of tumor necrosis (TN) of surgical specimens extracted in surgery was also evaluated.
  
  
  RESULTS
  Eighty four medical records from 1995 to 2015 were included. Both AP as LDH decreased in the patients studied, the pre CT value being higher than the post CT value. The average decrease of LHD was 272.95 U/L and AP was 10.17 U/L. The average tumor necrosis was 65.12 %. There was no statistical correlation between serums levels and the tumor necrosis percentage.
  
  
  CONCLUSIONS
  The serum levels values of AP and LDH are not predictors for chemotherapy-induced necrosis in patients with ES.Level of Evidence IV, Case Series.
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: André Mathias
authors.initials: AM
authors.lastname: Baptista
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Zumárraga
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Renan Pires Negrão
authors.initials: RP
authors.lastname: Dos Santos
authors.affiliation: . Hospital Regional do Gama, Orthopedics and Traumatology Unit, Brasília, DF, Brazil.
authors.forename: Guilherme de Oliveira
authors.initials: GO
authors.lastname: Haubert
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Department of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Olavo Pires
authors.initials: OP
authors.lastname: de Camargo
keywords: Ewing. Alkaline phosphatase. L-Lactate dehydrogenase. Tumor necrosis factor-alpha. Drug therapy. Prognosis.; Sarcoma