title: Alternative end points to evaluate a therapeutic strategy in advanced colorectal cancer: evaluation of progression-free survival, duration of disease control, and time to failure of strategy--an Aide et Recherche en Cancerologie Digestive Group Study.
abstract: OBJECTIVE
  Progression-free survival (PFS) is not an optimal end point to evaluate therapeutic strategies in advanced colorectal cancer (ACRC). Therefore, composite end points have been proposed to evaluate a chemotherapy strategy when sequential treatments are available: duration of disease control (DDC) and time to failure of strategy (TFS). The goal of this study was to evaluate these alternative end points and their potential surrogacy for overall survival (OS).
  
  
  METHODS
  We pooled individual patient data from three randomized trials evaluating chemotherapy strategy, which accrued 1,042 patients with previously untreated ACRC. In these trials, first-line treatment was either oxaliplatin- or irinotecan-based chemotherapy. Compared with TFS, DDC included neither time interval between progression and next sequence of treatment nor time to progression if the best result of the next sequence of treatment was progression.
  
  
  RESULTS
  There was good correlation between DDC and OS (correlation of median: r, 0.62; correlation of hazard ratio [HR]: adjusted copula R(2), 0.72) and between TFS and OS (correlation of median: r, 0.59; correlation of HR: adjusted copula R(2), 0.67). There was no correlation between PFS and OS (correlation of median: r, 0.45; correlation of HR: adjusted copula R(2), 0.47).
  
  
  CONCLUSIONS
  DDC and TFS roughly achieved the same results. Both are acceptable new end points to evaluate a therapeutic strategy in ACRC. Although TFS achieved a pragmatic evaluation of a multiline strategy, DDC captured the effect of a specific sequence in a therapeutic strategy.
authors.affiliation: Hôpital Saint-Antoine, Assistance Publique des Hôpitaux de Paris, 184, rue du faubourg Saint-Antoine, 75571, Paris Cedex 12, France.
authors.forename: Benoist
authors.initials: B
authors.lastname: Chibaudel
authors.forename: Franck
authors.initials: F
authors.lastname: Bonnetain
authors.forename: Qian
authors.initials: Q
authors.lastname: Shi
authors.forename: Marc
authors.initials: M
authors.lastname: Buyse
authors.forename: Christophe
authors.initials: C
authors.lastname: Tournigand
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Sargent
authors.forename: Carmen J
authors.initials: CJ
authors.lastname: Allegra
authors.forename: Richard M
authors.initials: RM
authors.lastname: Goldberg
authors.forename: Aimery
authors.initials: A
authors.lastname: de Gramont
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D018450:Disease Progression; D018572:Disease-Free Survival; D023381:Endpoint Determination; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D005602:France; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D016032:Randomized Controlled Trials as Topic; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D009944:Organoplatinum Compounds; D002955:Leucovorin; D005472:Fluorouracil; D002166:Camptothecin