title: Preoperative staging CT thorax in patients with colorectal cancer: its clinical importance.
abstract: BACKGROUND
  Recent studies suggest that there is little benefit to routine preoperative staging CT of the thorax in colorectal cancer.
  
  
  OBJECTIVE
  The current study hypothesized that staging CT of the thorax is not mandated in all patients with colorectal cancer.
  
  
  METHODS
  This study was a tertiary-care center retrospective observational study.
  
  
  METHODS
  Patients with a diagnosis of colon and rectal adenocarcinoma during 2006 to 2011 were included in a hospital database. Demographic, pathological, radiological, survival, and clinical factors were recorded. Three hundred eighty-two patients were included in the analysis (234 male, 148 female).
  
  
  METHODS
  All patients underwent preoperative staging CT of the thorax to determine the presence of pulmonary metastasis and/or indeterminate lesions.
  
  
  METHODS
  Patients demographics were reviewed, and the factors associated with pulmonary metastasis and indeterminate lesions were evaluated.
  
  
  RESULTS
  Distant metastases were evident in 61 patients (16%). CT scans revealed pulmonary metastasis in 23 patients (6%), and indeterminate lesions in 33 (8.6%). Only one-third of pulmonary lesions were evident on chest x-ray. On logistic regression analysis, nodal positivity was associated with an increased risk for pulmonary metastasis (p = 0.03). There was no difference in overall survival between patients with pulmonary metastasis and indeterminate lesions (p = 0.35, Kaplan-Meier estimate, log rank analysis). Pulmonary metastasis developed during postoperative surveillance in 7 patients with indeterminate lesions (21.2%).
  
  
  CONCLUSIONS
  This is a retrospective, single-center study with a relatively small sample size.
  
  
  CONCLUSIONS
  Pulmonary metastasis is relatively rare in colorectal cancer, and staging CT of the thorax may not be mandated in low-risk patients.
authors.affiliation: 1Department of Surgery, University Hospital Limerick, Limerick, Ireland 2Graduate Entry Medical School, University of Limerick, Limerick, Ireland 3Centre for Interventions in Infection, Inflammation and Immunity, Graduate Entry Medical School, University of Limerick, Ireland.
authors.forename: John
authors.initials: J
authors.lastname: Hogan
authors.forename: Colin
authors.initials: C
authors.lastname: O'Rourke
authors.forename: Gerald
authors.initials: G
authors.lastname: Duff
authors.forename: Michael
authors.initials: M
authors.lastname: Burton
authors.forename: Niall
authors.initials: N
authors.lastname: Kelly
authors.forename: John
authors.initials: J
authors.lastname: Burke
authors.forename: John Calvin
authors.initials: JC
authors.lastname: Coffey
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000556:secondary* / Q000601:surgery; D000368:Aged; D003110:Colonic Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D018570:Risk Assessment; D014057:Tomography, X-Ray Computed