title: CT Colonographic Screening of Patients With a Family History of Colorectal Cancer: Comparison With Adults at Average Risk and Implications for Guidelines.
abstract: OBJECTIVE
  The purposes of this study were to compare rates of lesion detection at CT colonographic (CTC) screening of adults without symptoms who had and who did not have a family history of colorectal cancer according to American Cancer Society guidelines and to consider the clinical implications.
  
  
  METHODS
  Over 134 months, consecutively registered CTC cohorts of adults without symptoms who had (n = 156; 88 [56.4%] women; 68 [43.6%] men; mean age, 56.3 years) and who did not have (n = 8857; 4757 [53.7%] women; 4100 [46.3%] men; mean age, 56.6 years) an American Cancer Society-defined family history of colorectal cancer (first-degree relative with diagnosis before age 60 years or two first-degree relatives with diagnosis at any age) were compared for relevant colorectal findings.
  
  
  RESULTS
  For the family history versus no family history cohorts, the frequency of all nondiminutive polyps (≥ 6 mm) reported at CTC was 23.7% versus 15.5% (p = 0.007); small polyps (6-9 mm), 13.5% versus 9.1% (p = 0.068); and large polyps (≥ 10 mm), 10.2% versus 6.5% (p = 0.068). The rate of referral for colonoscopy was greater for the family history cohort (16.0% vs 10.5%; p = 0.035). However, the frequencies of proven advanced adenoma (4.5% vs 3.2%; p = 0.357), nonadvanced adenoma (5.1% vs 2.6%; p = 0.070), and cancer (0.0% vs 0.4%; p = 0.999) were not significantly increased. The difference in positive rates between the two cohorts (11.5% vs 4.3%; p < 0.001) was primarily due to nonneoplastic findings of no colorectal cancer relevance, such as small hyperplastic polyps, diverticular disease, and false-positive CTC findings.
  
  
  CONCLUSIONS
  Although the overall CTC-positive and colonoscopy referral rates were higher in the family history cohort, the clinically relevant frequencies of advanced neoplasia and cancer were not sufficiently increased to preclude CTC screening. These findings support the use of CTC as a front-line screening option in adults with a family history of colorectal cancer.
authors.affiliation: 1 Department of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, 600 Highland Ave, Madison, WI 53792-3252.
authors.forename: Perry J
authors.initials: PJ
authors.lastname: Pickhardt
authors.affiliation: 1 Department of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, 600 Highland Ave, Madison, WI 53792-3252.
authors.forename: Ifeanyi
authors.initials: I
authors.lastname: Mbah
authors.affiliation: 1 Department of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, 600 Highland Ave, Madison, WI 53792-3252.
authors.forename: B Dustin
authors.initials: BD
authors.lastname: Pooler
authors.affiliation: 1 Department of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, 600 Highland Ave, Madison, WI 53792-3252.
authors.forename: Oliver T
authors.initials: OT
authors.lastname: Chen
authors.affiliation: 1 Department of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, 600 Highland Ave, Madison, WI 53792-3252.
authors.forename: J Louis
authors.initials: JL
authors.lastname: Hinshaw
authors.affiliation: 1 Department of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, 600 Highland Ave, Madison, WI 53792-3252.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Weiss
authors.affiliation: 1 Department of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, 600 Highland Ave, Madison, WI 53792-3252.
authors.forename: David H
authors.initials: DH
authors.lastname: Kim
mesh_terms: D000368:Aged; D023881:Colonography, Computed Tomographic / Q000592:standards / Q000706:statistics & numerical data*; D003113:Colonoscopy / Q000592:standards / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000235:genetics*; D055088:Early Detection of Cancer / Q000592:standards / Q000706:statistics & numerical data*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics; D006801:Humans; D008297:Male; D008487:Medical History Taking / Q000706:statistics & numerical data; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D015995:Prevalence; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014922:Wisconsin / Q000453:epidemiology
keywords: CT colonography; colorectal cancer; family history; screening; virtual colonoscopy