title: Survival following early-stage colon cancer: an ACCENT-based comparison of patients versus a matched international general population†.
abstract: BACKGROUND
  Post-treatment survival experience of early colon cancer (CC) patients is well described in the literature, which states that cure is probable for some patients. However, comparisons of treated patients' survival versus that expected from a matched general population (MGP) are limited.
  
  
  METHODS
  A total of 32 745 patients from 25 randomized adjuvant trials conducted from 1977 to 2012 in 41 countries were pooled. Observed long-term survival of these patients was compared with expected survival matched on sex, age, country, and year, both overall and by stage (II and III), sex, treatment [surgery, 5-fluorouracil (5-FU), 5-FU + oxaliplatin], age (<70 and 70+), enrollment year (pre/post 2000), and recurrence (yes/no). Comparisons were made at randomization and repeated conditional on survival to 1, 2, 3, and 5 years. CC and MGP equivalence was tested, and observed Kaplan-Meier survival rates compared with expected MGP rates 3 years out from each landmark. Analyses were also repeated in patients without recurrence.
  
  
  RESULTS
  Within most cohorts, long-term survival of CC patients remained statistically worse than the MGP, though conditional survival generally improved over time. Among those surviving 5 years, stage II, oxaliplatin-treated, elderly, and recurrence-free patients achieved subsequent 3-year survival rates within 5% of the MGP, with recurrence-free patients achieving equivalence.
  
  
  CONCLUSIONS
  Conditional on survival to 5 years, long-term survival of most CC patients on clinical trials remains modestly poorer than an MGP, but achieves MGP levels in some subgroups. These findings emphasize the need for access to quality care and improved treatment and follow-up strategies.
authors.affiliation: Division of Biomedical Statistics and Informatics. Electronic address: renfro.lindsay@mayo.edu.
authors.forename: L A
authors.initials: LA
authors.lastname: Renfro
authors.affiliation: Department of Oncology, Mayo Clinic, Rochester, USA.
authors.forename: A
authors.initials: A
authors.lastname: Grothey
authors.affiliation: Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
authors.forename: D
authors.initials: D
authors.lastname: Kerr
authors.affiliation: School of Medicine, University of Pennsylvania, Philadelphia, USA.
authors.forename: D G
authors.initials: DG
authors.lastname: Haller
authors.affiliation: Hôpital Saint Antoine, Paris; Pierre and Marie Curie University, Paris, France.
authors.forename: T
authors.initials: T
authors.lastname: André
authors.affiliation: Digestive Oncology Unit, University Hospital Gasthuisberg/Leuven, Leuven, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Van Cutsem
authors.affiliation: Gastrointestinal Oncology Service, Memorial Sloan-Kettering Cancer Center, New York, USA.
authors.forename: L
authors.initials: L
authors.lastname: Saltz
authors.affiliation: Oncology Unit, Ospedale Giovanni XXIII, Bergamo, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Labianca
authors.affiliation: Department of Oncology, Mayo Clinic, Rochester, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Loprinzi
authors.affiliation: Department of Oncology, Mayo Clinic, Rochester, USA.
authors.forename: S R
authors.initials: SR
authors.lastname: Alberts
authors.affiliation: Department for Internal Medicine IV, University Clinic Halle, Halle, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Schmoll
authors.affiliation: Leeds Institute of Cancer and Pathology, University of Leeds and St James's University Hospital, Leeds Cancer Research UK Centre, Leeds, UK.
authors.forename: C
authors.initials: C
authors.lastname: Twelves
authors.affiliation: National Surgical Adjuvant Breast and Bowel Project Biostatistical Center, Pittsburgh, USA.
authors.forename: G
authors.initials: G
authors.lastname: Yothers
authors.affiliation: Division of Biomedical Statistics and Informatics.
authors.forename: D J
authors.initials: DJ
authors.lastname: Sargent
mesh_terms: D016022:Case-Control Studies; D003110:Colonic Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D016208:Databases, Factual; D018572:Disease-Free Survival; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D015996:Survival Rate; D017741:Survivors; D013997:Time Factors; D016896:Treatment Outcome
keywords: early-stage colon cancer; individual patient data; long-term survival; meta-analysis; oxaliplatin chemotherapy; population