title: Protocol of the Definition for the Assessment of Time-to-event Endpoints in CANcer trials (DATECAN) project: formal consensus method for the development of guidelines for standardised time-to-event endpoints' definitions in cancer clinical trials.
abstract: BACKGROUND
  In randomised phase III cancer clinical trials, the most objectively defined and only validated time-to-event endpoint is overall survival (OS). The appearance of new types of treatments and the multiplication of lines of treatment have resulted in the use of surrogate endpoints for overall survival such as progression-free survival (PFS), or time-to-treatment failure. Their development is strongly influenced by the necessity of reducing clinical trial duration, cost and number of patients. However, while these endpoints are frequently used, they are often poorly defined and definitions can differ between trials which may limit their use as primary endpoints. Moreover, this variability of definitions can impact on the trial's results by affecting estimation of treatments' effects. The aim of the Definition for the Assessment of Time-to-event Endpoints in CANcer trials (DATECAN) project is to provide recommendations for standardised definitions of time-to-event endpoints in randomised cancer clinical trials.
  
  
  METHODS
  We will use a formal consensus methodology based on experts' opinions which will be obtained in a systematic manner.
  
  
  RESULTS
  Definitions will be independently developed for several cancer sites, including pancreatic, breast, head and neck and colon cancer, as well as sarcomas and gastrointestinal stromal tumours (GISTs).
  
  
  CONCLUSIONS
  The DATECAN project should lead to the elaboration of recommendations that can then be used as guidelines by researchers participating in clinical trials. This process should lead to a standardisation of the definitions of commonly used time-to-event endpoints, enabling appropriate comparisons of future trials' results.
authors.affiliation: Clinical and Epidemiological Research Unit, Institut Bergonié, Comprehensive Cancer Centre, Bordeaux, France.
authors.forename: Carine A
authors.initials: CA
authors.lastname: Bellera
authors.forename: Marina
authors.initials: M
authors.lastname: Pulido
authors.forename: Sophie
authors.initials: S
authors.lastname: Gourgou
authors.forename: Laurence
authors.initials: L
authors.lastname: Collette
authors.forename: Adélaïde
authors.initials: A
authors.lastname: Doussau
authors.forename: Andrew
authors.initials: A
authors.lastname: Kramar
authors.forename: Tienhan Sandrine
authors.initials: TS
authors.lastname: Dabakuyo
authors.forename: Monia
authors.initials: M
authors.lastname: Ouali
authors.forename: Anne
authors.initials: A
authors.lastname: Auperin
authors.forename: Thomas
authors.initials: T
authors.lastname: Filleron
authors.forename: Catherine
authors.initials: C
authors.lastname: Fortpied
authors.forename: Christophe
authors.initials: C
authors.lastname: Le Tourneau
authors.forename: Xavier
authors.initials: X
authors.lastname: Paoletti
authors.forename: Murielle
authors.initials: M
authors.lastname: Mauer
authors.forename: Simone
authors.initials: S
authors.lastname: Mathoulin-Pélissier
authors.forename: Franck
authors.initials: F
authors.lastname: Bonnetain
mesh_terms: D002986:Clinical Trials as Topic / Q000592:standards*; D023381:Endpoint Determination; D019317:Evidence-Based Medicine; D006801:Humans; D009369:Neoplasms / Q000401:mortality* / Q000628:therapy*; D017410:Practice Guidelines as Topic; D012107:Research Design; D011795:Surveys and Questionnaires; D015996:Survival Rate; D013997:Time Factors