Abdominal Radiology

, Volume 44, Issue 2, pp 429–437 | Cite as

Comparison of extracolonic findings and clinical outcomes in a screening and diagnostic CT colonography population

  • Michio TayaEmail author
  • Cody McHargue
  • Zina J. Ricci
  • Milana Flusberg
  • Stefanie Weinstein
  • Judy Yee



To compare the distribution of extracolonic findings and clinical outcomes between screening and diagnostic CT colonography (CTC) populations.


388 consecutive patients (369 men, 19 women; mean ± SD age 67.8 ± 10 years) who underwent first-time CTC (4/2011–4/2017) at a Veteran’s Affairs Medical Center were divided into screening (asymptomatic) or diagnostic (symptomatic) cohorts based on CTC indication. CTC reporting and data system E-scores for extracolonic findings were retrospectively assigned based on prospective CTC radiologic reports. Multinomial logistic regression was used to examine the association between E-scores and CTC indication. Electronic medical records of all patients with E3 or E4 scores were reviewed (median follow-up 2.8 years) to determine clinical outcomes.


68% (262/388) underwent screening and 32% (126/388) diagnostic CTC. 7.2% (28/388) had extracolonic findings considered potentially significant (E4), 4.4% (17/388) had indeterminate but likely unimportant findings (E3), and 88.4% (347/388) had normal or unimportant findings (E1 or E2). E-scores were not significantly different between screening and diagnostic CTC when adjusted for age, gender, and prior imaging (p = 0.44). 4.6% (12/262) of patients with E3/E4 findings in the screening cohort demonstrated clinically significant outcomes, compared with 4.0% (5/126) in the diagnostic cohort, including a total of three extracolonic malignancies (0.8%) and three abdominal aortic aneurysms (0.8%). 4.6% (18/388) underwent follow-up imaging studies to confirm a benign outcome after detection of a category E3/E4 finding.


The distribution of extracolonic findings and clinical outcomes were not statistically significantly different between screening and diagnostic CTC populations.


CT colonography Extracolonic findings C-RADS Screening 



We acknowledge the efforts of Kenny Ye, Ph.D. in statistical consultation.

Compliance with ethical standards


Judy Yee, MD, FACR has received research Grants from Echopixel and Philips. No other author has disclosures.

IRB Statement

This study was approved by the institutional review board. The requirement for informed consent was waived.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Radiology, Albert Einstein College of MedicineMontefiore Medical CenterBronxUSA
  2. 2.Department of RadiologySan Francisco Veterans Affairs Medical CenterSan FranciscoUSA
  3. 3.Department of Radiology and Biomedical ImagingUniversity of California San FranciscoSan FranciscoUSA
  4. 4.Graduate Medical EducationVirginia Mason Medical CenterSeattleUSA

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