Know Cancer

forgot password

Prospective Evaluation of Computer-Assisted, Non-Cathartic CT Colonography for Detection of Adenomatous Colonic Polyps in a Screening Cohort

Phase 2/Phase 3
50 Years
80 Years
Open (Enrolling)
Colonic Polyps

Thank you

Trial Information

Prospective Evaluation of Computer-Assisted, Non-Cathartic CT Colonography for Detection of Adenomatous Colonic Polyps in a Screening Cohort

Examinations to completely assess the colonic anatomy for the purposes of polyp detection
and cancer prevention all require an unpleasant, pre-exam cathartic bowel preparation. The
discomfort and embarrassment associated with this bowel prep has been identified as a
barrier to adherence of at-risk subjects with recommended colon screening guidelines. CT
Colonography (CTC) is an imaging based test that evaluates the entire colon anatomy and
requires cathartic bowel prep; its performance is considered comparable to optical
colonoscopy (OC) for adenomatous polyp detection. In addition, CTC generates a large amount
of data to be read by a human, and this data interpretation task can be aided by
computer-assisted-detection (CAD) software to identify potential polyp lesions for the human
reviewer. This trial studies the performance of a form of CTC that uses fecal tagging and
electronic image cleansing to obviate the need for cathartic prep. In addition, readings
prospectively employ CAD to potentially buffer human interpretation performance. The
investigators are prospectively testing this augmented (non-cathartic, CAD-assisted) form of
CTC in asymptomatic (screening) cohort. The trial is a prospective test comparison, using
segmentally unblinded optical colonoscopy in combination with pathology specimens as a
reference standard for presence of target lesions, adenomatous polyps 6 mm or greater in

Inclusion Criteria:

- age 50-80, eligible for colon screening

Exclusion Criteria:

- prior anatomic colon screening exam (optical colonoscopy, sigmoidoscopy, barium
enema, CT Colonography) within last 5 years

- personal history of inflammatory bowel disease, polyposis syndrome, colo-rectal
cancer, colon surgery

- documented passage of blood per rectum within last 12 months

Type of Study:


Study Design:

Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic

Outcome Measure:

Performance for detection of adenomatous colonic polyps > 6mm

Outcome Description:

this is a prospective test comparison of non-cathartic, CAD-assisted CT Colonography to segmentally unblinded optical colonoscopy (OC), latter serving with pathology specimens as reference standard for presence of polyps.

Outcome Time Frame:

on per subject basis, metric will be assessed at unblinding OC (w/i 5 weeks enrollment); for cohort, summary statistics will be generated at study completion

Safety Issue:


Principal Investigator

Michael Zalis, MD

Investigator Role:

Principal Investigator

Investigator Affiliation:

Massachusetts General Hospital


United States: Institutional Review Board

Study ID:




Start Date:

June 2005

Completion Date:

January 2011

Related Keywords:

  • Colonic Polyps
  • colon cancer
  • adenomatous colonic polyps
  • colon screening
  • CT Colonography (Virtual Colonoscopy)
  • Computer Aided Detection
  • Electronic Cleansing
  • Colonic Polyps
  • Polyps



Brigham and Women's Hospital Boston, Massachusetts  02115
Massachusetts General Hospital Boston, Massachusetts  02114-2617
UCSF-VA Medical Center San Francisco, California  94121