title: Soft tissue sarcomas of childhood and adolescence: the prognostic role of tumor size in relation to patient body size.
abstract: OBJECTIVE
  Tumor size is a key prognostic variable for soft tissue sarcomas (STS), and a tumor diameter of 5 cm is generally used as a cutoff for risk grouping purposes. This study aimed to investigate the prognostic effect of tumor size on overall survival and whether such an effect was influenced by the patient's size, expressed as body-surface area (BSA), in a series of 553 pediatric patients with localized STS.
  
  
  METHODS
  Multivariable Cox models were used in which the effect of tumor size was adjusted for patients age, tumor site, histologic subtype, and Intergroup Rhabdomyosarcoma Study grouping, and the interaction between size and BSA was included.
  
  
  RESULTS
  Tumor size was confirmed as a significant prognostic factor. Interaction between size and BSA meant that, for a given tumor size, the mortality increased from the larger to the smaller BSA. Conversely, the mortality risk associated with a patient with a BSA of 1.75 m(2) and a 5-cm tumor was the same as for a 0.6 m(2) child with a 2.8-cm tumor.
  
  
  CONCLUSIONS
  Tumor and body size are jointly informative on outcome. The risk associated with a given tumor size is not the same in patients of different body size, so it may be wrong to use the same 5-cm cutoff for tumor size in risk stratification.
authors.affiliation: Pediatric Oncology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Istituto Nazionale Tumori, Milano, Italy. andrea.ferrari@istitutotumori.mi.it
authors.forename: Andrea
authors.initials: A
authors.lastname: Ferrari
authors.forename: Rosalba
authors.initials: R
authors.lastname: Miceli
authors.forename: Cristina
authors.initials: C
authors.lastname: Meazza
authors.forename: Elena
authors.initials: E
authors.lastname: Zaffignani
authors.forename: Alessandro
authors.initials: A
authors.lastname: Gronchi
authors.forename: Luigi
authors.initials: L
authors.lastname: Piva
authors.forename: Paola
authors.initials: P
authors.lastname: Collini
authors.forename: Marta
authors.initials: M
authors.lastname: Podda
authors.forename: Maura
authors.initials: M
authors.lastname: Massimino
authors.forename: Roberto
authors.initials: R
authors.lastname: Luksch
authors.forename: Graziella
authors.initials: G
authors.lastname: Cefalo
authors.forename: Monica
authors.initials: M
authors.lastname: Terenziani
authors.forename: Filippo
authors.initials: F
authors.lastname: Spreafico
authors.forename: Daniela
authors.initials: D
authors.lastname: Polastri
authors.forename: Franca
authors.initials: F
authors.lastname: Fossati-Bellani
authors.forename: Michela
authors.initials: M
authors.lastname: Casanova
authors.forename: Luigi
authors.initials: L
authors.lastname: Mariani
mesh_terms: D000293:Adolescent; D001830:Body Surface Area; D002648:Child; D006801:Humans; D011379:Prognosis; D016016:Proportional Hazards Models; D012509:Sarcoma / Q000401:mortality* / Q000473:pathology*; D012983:Soft Tissue Neoplasms / Q000401:mortality* / Q000473:pathology*; D015996:Survival Rate; D055815:Young Adult