title: Progression-free Survival as a Surrogate End-point in Advanced Colorectal Cancer Treated with Antiangiogenic Therapies.
abstract: BACKGROUND
  It is not clear if progression-free survival (PFS) is a good surrogate end-point for overall survival (OS) for metastatic colorectal cancer if antiangiogenic therapies are used.
  
  
  METHODS
  We investigated randomized controlled trials testing antiangiogenic agents against chemotherapy. Log hazard ratios (HR) for PFS and OS were used to construct linear regression models. The surrogate threshold effect (STE) was calculated.
  
  
  RESULTS
  Thirteen studies and 24 comparison arms were available, including 7,179 patients. This model returned a significant correlation between PFS and OS (R(2)=0.68, p<0.001) with an STE of 0.83. Analysis restricted to first-line gave similar results (R(2)=0.68, p<0.001, STE=0.75).
  
  
  CONCLUSIONS
  There is a significant correlation between the effect of treatment on PFS and OS. PFS remains a good surrogate end-point for OS even if anti-angiogenic agents are used.
authors.affiliation: Oncology Department, Istituto Tumori Toscano (I.T.T.), Azienda Usl Toscana Centro, Ospedale Santa Maria Annunziata, Florence, Italy iago2003@libero.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Montagnani
authors.affiliation: Oncology Department, Istituto Tumori Toscano (I.T.T.), Azienda Usl Toscana Centro, Ospedale Santa Maria Annunziata, Florence, Italy.
authors.forename: Greta
authors.initials: G
authors.lastname: DI Leonardo
authors.affiliation: Oncology Department, Istituto Tumori Toscano (I.T.T.), Azienda Usl Toscana Centro, Ospedale Santa Maria Annunziata, Florence, Italy.
authors.forename: Maria Simona
authors.initials: MS
authors.lastname: Pino
authors.affiliation: Oncology Department, Istituto Tumori Toscano (I.T.T.), Azienda Usl Toscana Centro, Ospedale Santa Maria Annunziata, Florence, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Martella
authors.affiliation: Oncology Department, Istituto Tumori Toscano (I.T.T.), Azienda Usl Toscana Centro, Ospedale Santa Maria Annunziata, Florence, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Perboni
authors.affiliation: Oncology Department, Istituto Tumori Toscano (I.T.T.), Azienda Usl Toscana Centro, Ospedale Santa Maria Annunziata, Florence, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Ribecco
authors.affiliation: Oncology Department, Istituto Tumori Toscano (I.T.T.), Azienda Usl Toscana Centro, Ospedale Santa Maria Annunziata, Florence, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Fioretto
mesh_terms: D020533:Angiogenesis Inhibitors / Q000008:administration & dosage; D000068258:Bevacizumab / Q000008:administration & dosage*; D015415:Biomarkers; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000453:epidemiology / Q000473:pathology; D018572:Disease-Free Survival; D006801:Humans; D009389:Neovascularization, Pathologic / Q000188:drug therapy* / Q000453:epidemiology / Q000473:pathology; D016032:Randomized Controlled Trials as Topic
chemical_list: D020533:Angiogenesis Inhibitors; D015415:Biomarkers; D000068258:Bevacizumab
keywords: Angiogenesis; bevacizumab; colorectal cancer; progression-free survival; surrogate end-points