title: Incidence and predictors of bowel obstruction in elderly patients with stage IV colon cancer: a population-based cohort study.
abstract: OBJECTIVE
  Research has been limited on the incidence, mechanisms, etiology, and treatment of symptoms that require palliation in patients with terminal cancer. Bowel obstruction (BO) is a common complication of advanced abdominal cancer, including colon cancer, for which small, single-institution studies have suggested an incidence rate of 15% to 29%. Large population-based studies examining the incidence or risk factors associated with BO in cancer are lacking.
  
  
  OBJECTIVE
  To investigate the incidence and risk factors associated with BO in patients with stage IV colon cancer.
  
  
  METHODS
  Retrospective cohort, population-based study of patients in the Surveillance, Epidemiology, and End Results and Medicare claims linked databases who were diagnosed as having stage IV colon cancer from January 1, 1991, through December 31, 2005.
  
  
  METHODS
  Patients 65 years or older with stage IV colon cancer (n = 12 553).
  
  
  METHODS
  Time to BO, defined by inpatient hospitalization for BO. We used Cox proportional hazards regression models to determine associations between BO and patient, prior treatment, and tumor features.
  
  
  RESULTS
  We identified 1004 patients with stage IV colon cancer subsequently hospitalized with BO (8.0%). In multivariable analysis, proximal tumor site (hazard ratio, 1.22 [95% CI, 1.07-1.40]), high tumor grade (1.34 [1.16-1.55]), mucinous histological type (1.27 [1.08-1.50]), and nodal stage N2 (1.52 [1.26-1.84]) were associated with increased risk of BO, as was the presence of obstruction at cancer diagnosis (1.75 [1.47-2.04]). A more recent diagnosis was associated with decreased risk of subsequent obstruction (hazard ratio, 0.84 [95% CI, 0.72-0.98]).
  
  
  CONCLUSIONS
  In this large population of patients with stage IV colon cancer, BO after diagnosis was less common (8.0%) than previously reported. Risk was associated with site and histological type of the primary tumor. Future studies will explore management and outcomes in this serious, common complication.
authors.affiliation: Department of Surgery, Herbert Irving Comprehensive Cancer Center, College of Physicians and Surgeons, Columbia University, New York, New York4Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York.
authors.forename: Megan
authors.initials: M
authors.lastname: Winner
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Mooney
authors.forename: Dawn L
authors.initials: DL
authors.lastname: Hershman
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Feingold
authors.forename: John D
authors.initials: JD
authors.lastname: Allendorf
authors.forename: Jason D
authors.initials: JD
authors.lastname: Wright
authors.forename: Alfred I
authors.initials: AI
authors.lastname: Neugut
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007415:Intestinal Obstruction / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D008297:Male; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D012307:Risk Factors; D018426:SEER Program; D014481:United States / Q000453:epidemiology