title: Efficacy and toxicity of adjuvant chemotherapy in elderly patients with colorectal cancer: the ACCORE study.
abstract: BACKGROUND
  Elderly patients with primary colorectal cancer (CRC) are less frequently treated with adjuvant chemotherapy than younger patients due to concerns regarding toxicity and efficiency. We investigated how age, performance status (PS) and comorbidity influence treatment outcomes.
  
  
  METHODS
  A retrospective single-centre study of 529 patients with stages II-III CRC treated with adjuvant chemotherapy (5-fluorouracil/capecitabine+/÷oxaliplatin) from 2001 to 2011 at Herlev Hospital, Denmark. Baseline characteristics, chemotherapy and outcome were analysed with respect to age after adjusting for PS and comorbidity.
  
  
  RESULTS
  Elderly patients (>70 years) had significantly more comorbidity (p<0.001) and poorer PS (p=0.001) than younger patients. Elderly were more frequently treated with single-agent therapy (p=0.001) and at lower initial dose (p<0.001). There was no age-dependent difference in 3-year disease-free survival (DFS; HR 1.09, 95% CI 0.80 to 1.47, p=0.59), in grade 3-5 toxicity (29% vs 28%, p=0.86) or in 10-year CRC mortality (28%, HR 1.07, p=0.71). In elderly patients, a reduction in chemotherapy dose intensity compared with full dose had no impact on DFS or CRC mortality. Elderly patients receiving <50% of planned cycles had shorter DFS (HR=1.78, p=0.020) and higher CRC mortality (HR=2.17, p=0.027) than elderly receiving all cycles. Poor PS in younger and elderly patients was related to shorter DFS (HR=1.95, p=0.002; HR=1.6, p=0.035, respectively) and overall survival (OS; HR=2.28, p<0.001; HR=2.03, p=0.002). Comorbidity in younger patients was significantly related to shorter DFS (HR 2.72, p<0.001), OS (HR 3.16, p<0.001) and higher CRC mortality (HR 2.70, p=0.001).
  
  
  CONCLUSIONS
  Choice of regimen, primary dose reduction and given dose intensity in patients treated with adjuvant chemotherapy for CRC were highly dependent on age. However, age had no impact on DFS and CRC mortality. Comorbidity in younger patients and PS in all patients were associated with shorter DFS and higher CRC mortality.
authors.affiliation: Department of Medicine, Herlev and Gentofte Hospital, Copenhagen University, Herlev, Denmark; Department of Oncology, Herlev and Gentofte Hospital, Copenhagen University, Herlev, Denmark.
authors.forename: C M
authors.initials: CM
authors.lastname: Lund
authors.affiliation: Department of Oncology, Herlev and Gentofte Hospital, Copenhagen University, Herlev, Denmark; Faculty of Health and Medical Sciences, Department of Clinical Medicine,Copenhagen University, Copenhagen, Denmark.
authors.forename: D
authors.initials: D
authors.lastname: Nielsen
authors.affiliation: Danish Cancer Society Research Center, Danish Cancer Society , Copenhagen , Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Dehlendorff
authors.affiliation: Department of Oncology , Herlev and Gentofte Hospital , Copenhagen University , Herlev , Denmark.
authors.forename: A B
authors.initials: AB
authors.lastname: Christiansen
authors.affiliation: Department of Medicine , Herlev and Gentofte Hospital , Copenhagen University , Herlev , Denmark.
authors.forename: F
authors.initials: F
authors.lastname: Rønholt
authors.affiliation: Department of Medicine, Herlev and Gentofte Hospital, Copenhagen University, Herlev, Denmark; Department of Oncology, Herlev and Gentofte Hospital, Copenhagen University, Herlev, Denmark; Faculty of Health and Medical Sciences, Department of Clinical Medicine,Copenhagen University, Copenhagen, Denmark.
authors.forename: J S
authors.initials: JS
authors.lastname: Johansen
authors.affiliation: Department of Oncology , Herlev and Gentofte Hospital , Copenhagen University , Herlev , Denmark.
authors.forename: K K
authors.initials: KK
authors.lastname: Vistisen
keywords: adjuvant chemotherapy; colorectal cancer; comorbidity; elderly; performance status