title: CT colonography for combined colonic and extracolonic surveillance after curative resection of colorectal cancer.
abstract: OBJECTIVE
  To determine the accuracy of contrast material-enhanced computed tomographic (CT) colonography for postoperative surveillance in colorectal cancer patients without clinical or laboratory evidence of disease recurrence.
  
  
  METHODS
  The Institutional Review Board approved this HIPAA-compliant study and waived informed consent. Between January 2006 and December 2007, 742 consecutive patients without clinical or laboratory evidence of recurrence following curative-intent colorectal cancer surgery underwent contrast-enhanced CT colonography. Of these, 548 patients who had subsequent colonoscopy and pathologic confirmation of colonic lesions (reference standard) were included in the colonic analysis. All 742 patients were included in the extracolonic analysis. Sensitivity and specificity of CT colonography for nonanastomotic colonic lesions at least 6 mm in size and anastomotic lesions of any size, including performance according to lesion histologic type, were determined. Diagnostic yields of contrast-enhanced CT colonography for colonic cancers and for extracolonic recurrences were obtained.
  
  
  RESULTS
  CT colonography depicted all six metachronous cancers and one anastomotic recurrence within the colon in six patients (0.8%; 95% confidence interval [CI]: 0.3%, 1.8%]), for per-patient and per-lesion sensitivities of 100% (95% CIs: 64.3%, 100% and 67.8%, 100%, respectively). All cancer lesions within the colon were amenable to additional curative treatment. CT colonography per-patient and per-lesion sensitivity was 81.8% (95% CI: 60.9%, 93.3%) and 80.8% (95% CI: 64.3%, 97.2%), respectively, for advanced neoplasia and 80.0% (95% CI: 68.6%, 88.1%) and 78.5% (95% CI: 68.3%, 88.7%), respectively, for all adenomatous lesions. Negative predictive values for adenocarcinoma, advanced neoplasia, and all adenomatous lesions were 100%, 99.1%, and 97.0%, respectively. CT colonography specificity was 93.1% (95% CI: 90.4%, 95.2%). Contrast-enhanced CT colonography enabled detection of extracolonic recurrences in an additional 11 patients (1.5%; 95% CI: 0.8%, 2.7%).
  
  
  CONCLUSIONS
  Contrast-enhanced CT colonography is an accurate and practical surveillance tool following colorectal cancer surgery in patients without clinical or laboratory evidence of recurrence, allowing for simultaneous less-invasive evaluation of both colon and extracolonic organs.
  
  
  BACKGROUND
  http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100385/-/DC1.
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Asanbyeongwon-gil 86, Songpa-Gu, Seoul 138-736, Republic of Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Park
authors.forename: Perry J
authors.initials: PJ
authors.lastname: Pickhardt
authors.forename: Sang Nam
authors.initials: SN
authors.lastname: Yoon
authors.forename: Seung Soo
authors.initials: SS
authors.lastname: Lee
authors.forename: Judy
authors.initials: J
authors.lastname: Yee
authors.forename: David H
authors.initials: DH
authors.lastname: Kim
authors.forename: Ah Young
authors.initials: AY
authors.lastname: Kim
authors.forename: Jin Cheon
authors.initials: JC
authors.lastname: Kim
authors.forename: Chang Sik
authors.initials: CS
authors.lastname: Yu
authors.forename: Hyun Kwon
authors.initials: HK
authors.lastname: Ha
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D023881:Colonography, Computed Tomographic / Q000379:methods*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media