title: Comorbidity, age and overall survival in cetuximab-treated patients with advanced colorectal cancer (ACRC)--results from NCIC CTG CO.17: a phase III trial of cetuximab versus best supportive care.
abstract: BACKGROUND
  the interplay between comorbidity, age and performance status (PS) as predictors of outcome in advanced colorectal cancer (ACRC) is poorly understood. We examined these factors as predictors of treatment toxicity and outcome in cetuximab-treated patients with ACRC.
  
  
  METHODS
  comorbidity was independently evaluated using the Charlson Comorbidity Index (CCI), a validated measure of comorbidity based on the presence of medical conditions weighted according to their effect on mortality. CCI score was correlated with clinical and outcome data.
  
  
  RESULTS
  five hundred and seventy-two patients were included; 41% were ≥ 65 years and 25% had comorbidities at randomization. In multivariate analysis (MVA) of all covariates, only older age was associated with greater comorbidity (P = 0.008). Overall survival (OS) was significantly better for patients with greater comorbidity in univariate analysis (P = 0.047). Conversely, better PS was associated with better OS in MVA (hazard ratio 1.92 for PS = 2 versus PS = 0, P < 0.0001). Age was not associated with OS (P = 0.13). Elderly patients had significantly less grade ≥ 3 vomiting (P = 0.034) but more dyspnea (P = 0.005). Patients with greater comorbidity had significantly less grade ≥ 3 vomiting (P =  0.002) but more non-neutropenic fever (P = 0.005).
  
  
  CONCLUSIONS
  better PS was associated with improved OS. For patients with good PS, restricting cetuximab use in the setting of significant comorbidity does not appear justified.
authors.affiliation: Department of Medical Oncology, The Ottawa Hospital Cancer Centre, Ottawa, Ontario, Canada. Electronic address: tasmis@ottawahospital.on.ca.
authors.forename: T R
authors.initials: TR
authors.lastname: Asmis
authors.affiliation: Department of Medical Oncology, The Ottawa Hospital Cancer Centre, Ottawa, Ontario, Canada.
authors.forename: E
authors.initials: E
authors.lastname: Powell
authors.affiliation: Department of Medical Oncology, Flinders Medical Centre, Bedford Park, South Australia, Australia.
authors.forename: C S
authors.initials: CS
authors.lastname: Karapetis
authors.affiliation: Department of Medical Oncology, The Ottawa Hospital Cancer Centre, Ottawa, Ontario, Canada.
authors.forename: D J
authors.initials: DJ
authors.lastname: Jonker
authors.affiliation: NCIC-Clinical Trials Group, Kingston, Ontario, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Tu
authors.affiliation: Oncology Department, Christchurch Hospital, Christchurch, New Zealand.
authors.forename: M
authors.initials: M
authors.lastname: Jeffery
authors.affiliation: Department of Medical Oncology, Royal North Shore Hospital, Sydney, New South Wales, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Pavlakis
authors.affiliation: Department of Medical Oncology, Royal Melbourne and Western Hospital, Melbourne, Victoria, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Gibbs
authors.affiliation: NCIC-Clinical Trials Group, Kingston, Ontario, Canada.
authors.forename: L
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Medical Oncology, Thunder Bay Regional Health Sciences Centre, Thunder Bay, Ontario, Canada.
authors.forename: D-A
authors.initials: DA
authors.lastname: Dueck
authors.affiliation: Department of Medical Oncology, Hopital du Sacre-Coeur de Montreal, Montreal, Quebec, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Whittom
authors.affiliation: Bristol-Myers Squibb, Lawrenceville, NJ, USA.
authors.forename: C
authors.initials: C
authors.lastname: Langer
authors.affiliation: NCIC-Clinical Trials Group, Kingston, Ontario, Canada.
authors.forename: C J
authors.initials: CJ
authors.lastname: O'Callaghan
mesh_terms: D000367:Age Factors; D000368:Aged; D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000068818:Cetuximab; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000628:therapy*; D015897:Comorbidity; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D010166:Palliative Care / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000068818:Cetuximab