title: Effect of delay in adjuvant oxaliplatin-based chemotherapy for stage III colon cancer.
abstract: BACKGROUND
  Less than 8 weeks has been recommended as the optimal time to initiate AC based on 2 meta-analyses that suggested worse survival with delayed AC. However, neither study included patients treated with an oxaliplatin-based chemotherapy. We aimed to investigate the effect of delay in initiating oxaliplatin-based chemotherapy on RFS and CSS for stage III colon cancer.
  
  
  METHODS
  Records of patients who initiated oxaliplatin-based AC for stage III colon cancer between 2006 and 2011 at the British Columbia Cancer Agency were retrospectively reviewed. Cox proportional models were used to analyze the effect of time to AC (TTAC) on RFS and CSS. TTAC was categorized into ≤ 8 weeks (G1) and > 8 weeks (G2).
  
  
  RESULTS
  Six hundred thirty-five patients were included (G1, n = 291; G2, n = 344). Median time from surgery to initiation of AC was 8.3 weeks. At a median follow-up of 57.9 months, 176 patients (27.7%) had disease recurrence and 118 (18.6%) had died. Five-year RFS was 70.9% (95% confidence interval [CI], 65.2-76.5) for G1 and 72.1% (95% CI, 67.2-77) for G2. Five-year CSS was 82% for G1 (95% CI, 87.09-76.91) and 82.8% for G2 (95% CI, 78.30-87.30). On multivariate analysis, delayed TTAC did not have prognostic significance on either RFS (hazard ratio [HR], 1.08; P = .609) or CSS (HR, 1.02; P = .893).
  
  
  CONCLUSIONS
  In our population-based study, TTAC after stage III colon cancer resection did not have an effect on RFS or CSS. Contrary to most of the existing data, which are primarily based on 5-fluorouracil-based AC, delay of oxaliplatin-based AC beyond 8 weeks did not appear to be associated with inferior outcomes.
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada. Electronic address: renatadalpino@gmail.com.
authors.forename: Renata D'Alpino
authors.initials: RD
authors.lastname: Peixoto
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Aalok
authors.initials: A
authors.lastname: Kumar
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Caroline
authors.initials: C
authors.lastname: Speers
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Renouf
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Hagen F
authors.initials: HF
authors.lastname: Kennecke
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Howard J
authors.initials: HJ
authors.lastname: Lim
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Winson Y
authors.initials: WY
authors.lastname: Cheung
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Barbara
authors.initials: B
authors.lastname: Melosky
authors.affiliation: Division of Medical Oncology, University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
authors.forename: Sharlene
authors.initials: S
authors.lastname: Gill
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage* / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant / Q000379:methods*; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D005472:Fluorouracil
keywords: Adjuvant chemotherapy; Colon cancer; Oxaliplatin; Surgery; Timing of chemotherapy