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CompletedNCT00084929ACRIN6664Updated Dec 22, 2020Results posted

The National CT Colonography Trial

An interventional study of CT Colonography in Colorectal Cancer, sponsored by American College of Radiology Imaging Network. Completed at 14 sites in United States. Open to participants aged 50 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2020-12-22.

Sponsored by American College of Radiology Imaging Network · Not applicable, Interventional, and Screening

Phase
Not applicable
Study type
Interventional
Enrollment
2,600
Allocation
Not applicable
Ages
50 Years and older
Sex
All
01

Study summary

RATIONALE: New diagnostic procedures such as computed tomographic colonography may improve the ability to detect colorectal cancer and may provide a less invasive method of detection.

PURPOSE: This clinical trial is studying how well computed tomographic colonography works in screening healthy participants for colorectal cancer.

Read the detailed description

OBJECTIVES:

Primary

  • Compare the sensitivity of computed tomographic colonography (CTC) vs colonoscopy for detecting significantly large lesions (≥ 10 mm in diameter) in asymptomatic participants, in terms of specificity, area under the ROC curve, and predictive values for detecting clinically significant colorectal neoplasia.

Secondary

  • Determine the interobserver variation in accuracy of interpreting CTC examinations of these participants, including any benefits of a primary 3-dimensional read and/or independent second interpretations.
  • Determine the effects of different colon preparations on the accuracy of CTC in these participants.
  • Compare participant acceptance and willingness to have a repeat examination by CTC vs colonoscopy.
  • Determine the accuracy of CTC in detecting flat lesions in the colon of these participants.

OUTLINE: This is a multicenter study.

Participants receive an oral laxative, oral bisacodyl, and three doses of oral barium sulphate 24 hours before imaging. After cathartic cleansing, participants undergo computed tomographic colonography followed by colonoscopy.

Participants are followed up for approximately 4 weeks.

PROJECTED ACCRUAL: A total of 2,607 participants will be accrued for this study.

02

Conditions studied

  • Colorectal Cancer

Keywords

  • colon cancer
  • rectal cancer
03

In context

Colorectal Neoplasms

5,599 studies on the registry are indexed under Colorectal Neoplasms; 1,459 are open to participants now.

This study's enrollment of 2,600 is above the median of 77 across 4,123 interventional studies indexed under Colorectal Neoplasms.

Browse Colorectal Neoplasms studies →

Lead sponsor

American College of Radiology Imaging Network is the lead sponsor of 21 studies on the registry; none are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
50 Years and older
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Male or female outpatients

    • Aged 50 years or older
    • Scheduled for screening colonoscopy
    • Participant's signed informed consent

Exclusion criteria

  • Symptoms of disease of the lower gastrointestinal tract, including

    • Melanotic stools or/and hematochezia on more than one occasion in the previous six months
    • Lower abdominal pain that would normally require a medical evaluation
    • Inflammatory bowel disease and/or familial polyposis syndrome
    • Serious medical conditions that would increase the risk associated with colonoscopy or are so severe that screening would have no benefit
    • Pregnancy
    • Previous colonoscopy within the past five years
    • Anemia (hemoglobin less than 10 gm/dl)
    • Positive fecal occult blood test (FOBT)
05

Study design

Phase
Not applicable
Primary purpose
Screening
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
2,600 participants (actual)

Study arms

  • Experimental
    CT Colonography

    CT colonography conducted during the same assessment as colonoscopy.

    Procedure: CT Colonography

Interventions

  • ProcedureCT Colonography

    CT colonography performed for comparison with colonoscopy results performed during the same screening assessment.

    Also known as: CT colonography trial, colonoscopy

06

What researchers measure

Primary outcomes

  1. Number of Participants With Advanced Adenomas (>=10mm) as Determined by Colonoscopy (Per Patient)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=10mm (as measured at pathology) RS-: No Advanced adenomas \>=10mm found by colonoscopy (as measured at pathology)

    Time frame: within 30 days

  2. Number of Participants With Advanced Adenomas (>=9mm) Detected by CT Colonoscopy (Per Patient)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=9mm (as measured at pathology) RS-: No Advanced adenomas \>=9mm found by colonoscopy (as measured at pathology)

    Time frame: within 30 days

  3. Number of Participants With Advanced Adenomas (>=8mm) Detected by CT Colonoscopy (Per Patient)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=8mm (as measured at pathology) RS-: No Advanced adenomas \>=8mm found by colonoscopy (as measured at pathology)

    Time frame: within 30 days

  4. Number of Participants With Advanced Adenomas (>=7mm) Detected by CT Colonoscopy (Per Patient)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=7mm (as measured at pathology) RS-: No Advanced adenomas \>=7mm found by colonoscopy (as measured at pathology)

    Time frame: within 30 days

  5. Number of Participants With Advanced Adenomas (>=6mm) Detected by CT Colonoscopy (Per Patient)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=6mm (as measured at pathology) RS-: No Advanced adenomas \>=16mm found by colonoscopy (as measured at pathology)

    Time frame: within 30 days

  6. Number of Participants With Advanced Adenomas (>=5mm) Detected by CT Colonoscopy (Per Patient)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=5mm (as measured at pathology) RS-: No Advanced adenomas \>=5mm found by colonoscopy (as measured at pathology)

    Time frame: within 30 days

Secondary outcomes

  1. Number of Advanced Adenoma or Cancer Lesions (>=10mm) Detected by CT Colonoscopy (Per Lesion)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

    Time frame: within 30 days

  2. Number of Advanced Adenoma or Cancer Lesions (>=9mm) Detected by CT Colonoscopy (Per Lesion)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

    Time frame: within 30 days

  3. Number of Advanced Adenoma or Cancer Lesions (>=8mm) Detected by CT Colonoscopy (Per Lesion)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

    Time frame: within 30 days

  4. Number of Advanced Adenoma or Cancer Lesions (>=7mm) Detected by CT Colonoscopy (Per Lesion)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

    Time frame: within 30 days

  5. Number of Advanced Adenoma or Cancer Lesions (>=6mm) Detected by CT Colonoscopy (Per Lesion)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

    Time frame: within 30 days

  6. Number of Advanced Adenoma or Cancer Lesions (>=5mm) Detected by CT Colonoscopy (Per Lesion)

    Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

    Time frame: within 30 days

  7. Interobserver Sensitivity Variability

    Evaluate interobserver variability in Sensitivity (P(T+\|D+)) and 95% CI) when interpreting CTC examinations Each study was randomly assigned to be read independently using either a primary 2D search method (conventional 2D image display with 3D endoluminal problem solving), or a primary 3D search method (including the capability of displaying multiplanar 2D) and without prior knowledge of the colonoscopy results. A second trained radiologist of similar skill was assigned to read the images using the other modality Readers were then classified as high performing or not high performing

    Time frame: at baseline

07

Results

Posted Nov 16, 2020

Participant flow

2600 asymptomatic, out-patients, 50 years or older and prescheduled for screening colonoscopy were recruited for CTC between February 2005 and December 2006.

Participant flow — Overall Study
MilestoneCT Colonography
Started2600
Completed2531
Not completed69
Withdrew: Ineligible - medical contraindication1
Withdrew: Ineligible - pre-scheduled procedure not1
Withdrew: Ineligible - medical history6
Withdrew: Withdrawal by subject10
Withdrew: Missing/incomplete ctc exam9
Withdrew: Missing reference standard (colonoscopy)42

Outcome measures

PrimaryNumber of Participants With Advanced Adenomas (>=10mm) as Determined by Colonoscopy (Per Patient)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=10mm (as measured at pathology) RS-: No Advanced adenomas \>=10mm found by colonoscopy (as measured at pathology)

Time frame:
within 30 days
Reported as:
Count of participants · Participants
Number of Participants With Advanced Adenomas (>=10mm) as Determined by Colonoscopy (Per Patient)
ParticipantsCT Colonography
RS+109
RS-2422
Statistical analysis
  • CT Colonography · Area under the curve (auc): 0.89 · 95% CI 0.853 to 0.933
  • CT Colonography · Sensitivity: p(t+|d+): 0.9 · 95% CI 0.838 to 0.96Exact 95% confidence intervals were calculated for each radiologist, and large-sample 95% confidence intervals were calculated for overall estimates, with the use of standard errors that allowed for estimation of variation among radiologists.
  • CT Colonography · P(t-|d-): 0.86 · 95% CI 0.813 to 0.9Exact 95% confidence intervals were calculated for each radiologist, and large-sample 95% confidence intervals were calculated for overall estimates, with the use of standard errors that allowed for estimation of variation among radiologists.
  • CT Colonography · P(d+|t+): 0.23 · 95% CI 0.194 to 0.273Exact 95% confidence intervals were calculated for each radiologist, and large-sample 95% confidence intervals were calculated for overall estimates, with the use of standard errors that allowed for estimation of variation among radiologists.
  • CT Colonography · P(d-|t-): 0.99 · 95% CI 0.990 to 0.998Exact 95% confidence intervals were calculated for each radiologist, and large-sample 95% confidence intervals were calculated for overall estimates, with the use of standard errors that allowed for estimation of variation among radiologists.
PrimaryNumber of Participants With Advanced Adenomas (>=9mm) Detected by CT Colonoscopy (Per Patient)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=9mm (as measured at pathology) RS-: No Advanced adenomas \>=9mm found by colonoscopy (as measured at pathology)

Time frame:
within 30 days
Reported as:
Count of participants · Participants
Number of Participants With Advanced Adenomas (>=9mm) Detected by CT Colonoscopy (Per Patient)
ParticipantsCT Colonography
RS+: Advanced Adenoma >=9mm120
RS-: Not Advanced Adenoma >=9mm2411
Statistical analysis
  • CT Colonography · Area under the curve (auc): 0.89 · 95% CI 0.853 to 0.93
  • CT Colonography · Sensitivity: p(t+|d+): 0.9 · 95% CI 0.832 to 0.96Sensitivity indicates the percent of patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
  • CT Colonography · P(t-|d-): 0.86 · 95% CI 0.817 to 0.902Specificity indicates the percent of patients who had not lesions detected on optical colonoscopy, who had no lesions detected on CTC.
  • CT Colonography · P(d+|t+): 0.25 · 95% CI 0.209 to 0.292
  • CT Colonography · P(d-|t-): 0.99 · 95% CI 0.990 to 0.998
PrimaryNumber of Participants With Advanced Adenomas (>=8mm) Detected by CT Colonoscopy (Per Patient)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=8mm (as measured at pathology) RS-: No Advanced adenomas \>=8mm found by colonoscopy (as measured at pathology)

Time frame:
within 30 days
Reported as:
Count of participants · Participants
Number of Participants With Advanced Adenomas (>=8mm) Detected by CT Colonoscopy (Per Patient)
ParticipantsCT Colonography
RS+: Advanced Adenoma >=8mm154
RS-: Not Advanced Adenoma >=8mm2377
Statistical analysis
  • CT Colonography · Area under the curve (auc): 0.88 · 95% CI 0.842 to 0.913
  • CT Colonography · Sensitivity: p(t+|d+): 0.87 · 95% CI 0.803 to 0.929Sensitivity indicates the percent of patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
  • CT Colonography · P(t-|d-): 0.87 · 95% CI 0.825 to 0.909Specificity indicates the percent of patients who had not lesions detected on optical colonoscopy, who had no lesions detected on CTC.
  • CT Colonography · P(d+|t+): 0.31 · 95% CI 0.256 to 0.355
  • CT Colonography · P(d-|t-): 0.99 · 95% CI 0.984 to 0.994
PrimaryNumber of Participants With Advanced Adenomas (>=7mm) Detected by CT Colonoscopy (Per Patient)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=7mm (as measured at pathology) RS-: No Advanced adenomas \>=7mm found by colonoscopy (as measured at pathology)

Time frame:
within 30 days
Reported as:
Count of participants · Participants
Number of Participants With Advanced Adenomas (>=7mm) Detected by CT Colonoscopy (Per Patient)
ParticipantsCT Colonography
RS+: Advanced Adenoma >=7mm174
RS-: Not Advanced Adenoma >=7mm2357
Statistical analysis
  • CT Colonography · Area under the curve (auc): 0.87 · 95% CI 0.833 to 0.902
  • CT Colonography · Sensitivity: p(t+|d+): 0.84 · 95% CI 0.776 to 0.912Sensitivity indicates the percent of patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
  • CT Colonography · P(t-|d-): 0.87 · 95% CI 0.831 to 0.914Specificity indicates the percent of patients who had not lesions detected on optical colonoscopy, who had no lesions detected on CTC.
  • CT Colonography · P(d+|t+): 0.35 · 95% CI 0.299 to 0.397
  • CT Colonography · P(d-|t-): 0.99 · 95% CI 0.980 to 0.992
PrimaryNumber of Participants With Advanced Adenomas (>=6mm) Detected by CT Colonoscopy (Per Patient)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=6mm (as measured at pathology) RS-: No Advanced adenomas \>=16mm found by colonoscopy (as measured at pathology)

Time frame:
within 30 days
Reported as:
Count of participants · Participants
Number of Participants With Advanced Adenomas (>=6mm) Detected by CT Colonoscopy (Per Patient)
ParticipantsCT Colonography
RS+: Advanced Adenoma >=6mm210
RS-: Not Advanced Adenoma >=6mm2321
Statistical analysis
  • CT Colonography · Area under the curve (auc): 0.84 · 95% CI 0.810 to 0.878
  • CT Colonography · Sensitivity: p(t+|d+): 0.78 · 95% CI 0.711 to 0.849Sensitivity indicates the percent of patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
  • CT Colonography · P(t-|d-): 0.88 · 95% CI 0.840 to 0.92Specificity indicates the percent of patients who had not lesions detected on optical colonoscopy, who had no lesions detected on CTC.
  • CT Colonography · P(d+|t+): 0.4 · 95% CI 0.335 to 0.463
  • CT Colonography · P(d-|t-): 0.98 · 95% CI 0.971 to 0.984
PrimaryNumber of Participants With Advanced Adenomas (>=5mm) Detected by CT Colonoscopy (Per Patient)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard (RS) for determining the existence of advanced adenomas. RS+: Colonoscopy found at least 1 Advanced adenomas \>=5mm (as measured at pathology) RS-: No Advanced adenomas \>=5mm found by colonoscopy (as measured at pathology)

Time frame:
within 30 days
Reported as:
Count of participants · Participants
Number of Participants With Advanced Adenomas (>=5mm) Detected by CT Colonoscopy (Per Patient)
ParticipantsCT Colonography
RS+: Advanced Adenoma >=5mm282
RS-: Not Advanced Adenoma >=5mm2249
Statistical analysis
  • CT Colonography · Area under the curve (auc): 0.8 · 95% CI 0.763 to 0.828
  • CT Colonography · Sensitivity: p(t+|d+): 0.65 · 95% CI 0.579 to 0.727Sensitivity indicates the percent of patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
  • CT Colonography · P(t-|d-): 0.89 · 95% CI 0.851 to 0.923Specificity indicates the percent of patients who had not lesions detected on optical colonoscopy, who had no lesions detected on CTC.
  • CT Colonography · P(d+|t+): 0.45 · 95% CI 0.389 to 0.513
  • CT Colonography · P(d-|t-): 0.95 · 95% CI 0.941 to 0.965
SecondaryNumber of Advanced Adenoma or Cancer Lesions (>=10mm) Detected by CT Colonoscopy (Per Lesion)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

Time frame:
within 30 days
Reported as:
Count of units · lesions
Number of Advanced Adenoma or Cancer Lesions (>=10mm) Detected by CT Colonoscopy (Per Lesion)
lesionsCT Colonography (Per Lesion)
Detected by CTC108
Not Detected20
Statistical analysis
  • CT Colonography (Per Lesion) · Sensitivity: p(t+|d+): 0.84Sensitivity indicates the percent of lesions in patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
SecondaryNumber of Advanced Adenoma or Cancer Lesions (>=9mm) Detected by CT Colonoscopy (Per Lesion)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

Time frame:
within 30 days
Reported as:
Count of units · lesions
Number of Advanced Adenoma or Cancer Lesions (>=9mm) Detected by CT Colonoscopy (Per Lesion)
lesionsCT Colonography (Per Lesion)
Detected by CTC117
Not Detected26
Statistical analysis
  • CT Colonography (Per Lesion) · Sensitivity: p(t+|d+): 0.82Sensitivity indicates the percent of lesions in patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
SecondaryNumber of Advanced Adenoma or Cancer Lesions (>=8mm) Detected by CT Colonoscopy (Per Lesion)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

Time frame:
within 30 days
Reported as:
Count of units · lesions
Number of Advanced Adenoma or Cancer Lesions (>=8mm) Detected by CT Colonoscopy (Per Lesion)
lesionsCT Colonography (Per Lesion)
Detected by CTC149
Not Detected38
Statistical analysis
  • CT Colonography (Per Lesion) · Sensitivity: p(t+|d+): 0.8Sensitivity indicates the percent of lesions in patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
SecondaryNumber of Advanced Adenoma or Cancer Lesions (>=7mm) Detected by CT Colonoscopy (Per Lesion)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

Time frame:
within 30 days
Reported as:
Count of units · lesions
Number of Advanced Adenoma or Cancer Lesions (>=7mm) Detected by CT Colonoscopy (Per Lesion)
lesionsCT Colonography (Per Lesion)
Detected by CTC165
Not Detected55
Statistical analysis
  • CT Colonography (Per Lesion) · Sensitivity: p(t+|d+): 0.75Sensitivity indicates the percent of lesions in patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
SecondaryNumber of Advanced Adenoma or Cancer Lesions (>=6mm) Detected by CT Colonoscopy (Per Lesion)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

Time frame:
within 30 days
Reported as:
Count of units · lesions
Number of Advanced Adenoma or Cancer Lesions (>=6mm) Detected by CT Colonoscopy (Per Lesion)
lesionsCT Colonography (Per Lesion)
Detected by CTC189
Not Detected81
Statistical analysis
  • CT Colonography (Per Lesion) · Sensitivity: p(t+|d+): 0.7Sensitivity indicates the percent of lesions in patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
SecondaryNumber of Advanced Adenoma or Cancer Lesions (>=5mm) Detected by CT Colonoscopy (Per Lesion)

Pathology results from Colonoscopy performed up to 30 days after a CTC examination were used as the reference standard for determining the existence of advanced adenomas. CTC lesions needed to be within 2 segments and 50% size of the lesions removed via colonoscopy to be considered "detected"

Time frame:
within 30 days
Reported as:
Count of units · lesions
Number of Advanced Adenoma or Cancer Lesions (>=5mm) Detected by CT Colonoscopy (Per Lesion)
lesionsCT Colonography (Per Lesion)
Detected by CTC221
Not Detected153
Statistical analysis
  • CT Colonography (Per Lesion) · Sensitivity: p(t+|d+): 0.59Sensitivity indicates the percent of lesions in patients who had a lesions (of the specified size) detected by optical colonoscopy, which were detected by CTC
SecondaryInterobserver Sensitivity Variability

Evaluate interobserver variability in Sensitivity (P(T+\|D+)) and 95% CI) when interpreting CTC examinations Each study was randomly assigned to be read independently using either a primary 2D search method (conventional 2D image display with 3D endoluminal problem solving), or a primary 3D search method (including the capability of displaying multiplanar 2D) and without prior knowledge of the colonoscopy results. A second trained radiologist of similar skill was assigned to read the images using the other modality Readers were then classified as high performing or not high performing

Time frame:
at baseline
Reported as:
Mean · probability of (test+ given disease+)
Interobserver Sensitivity Variability
probability of (test+ given disease+)High Performance (HP) ReadersNon-high Performance (NHP) Readers
Interobserver Sensitivity Variability0.94 (0.825 to 0.987)0.88 (0.864 to 0.901)

Adverse events

Collected over The adverse event reporting period for this protocol is defined as the period from the initiation of the Computed Tomography Colonography (CTC) procedure and self-reported events were collected for 30 days after the last primary intervention. All participants were monitored for 30days.. Non-serious events are listed at a 1% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
CT Colonography0/2,600 (0%)0/2,600 (0%)0/2,600 (0%)
Colonoscopy0/2,600 (0%)1/2,600 (0%)0/2,600 (0%)
Most frequent serious events
Most frequent serious events
EventCT ColonographyColonoscopy
hemorrhage with surgeryGastrointestinal disorders0/26001/2600

Baseline characteristics

Age, Continuous
Age, Continuous(years)CT Colonography
Mean58 ± 7.0
Sex: Female, Male
Sex: Female, Male(Participants)CT Colonography
Female1326
Male1205
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)CT Colonography
Hispanic or Latino97
Not Hispanic or Latino2430
Unknown or Not Reported4
Race (NIH/OMB)
Race (NIH/OMB)(Participants)CT Colonography
American Indian or Alaska Native10
Asian54
Native Hawaiian or Other Pacific Islander3
Black or African American325
White2075
More than one race20
Unknown or Not Reported44
08

Study locations

14 sites
  • Mayo Clinic Scottsdale
    Scottsdale, Arizona 85259-5499, United States
  • Moores UCSD Cancer Center
    La Jolla, California 92093-0658, United States
  • Jonsson Comprehensive Cancer Center at UCLA
    Los Angeles, California 90095-1781, United States
  • Veterans Affairs Medical Center - San Francisco
    San Francisco, California 94121, United States
  • Invision/Radiology Imaging Associates - Englewood
    Englewood, Colorado 80112, United States
  • Yale Cancer Center
    New Haven, Connecticut 06520-8028, United States
  • University of Chicago Cancer Research Center
    Chicago, Illinois 60637-1470, United States
  • Clinical Radiologists, S.C. at Memorial Medical Center
    Springfield, Illinois 62781, United States
  • Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins
    Baltimore, Maryland 21231-2410, United States
  • Beth Israel Deaconess Medical Center
    Boston, Massachusetts 02215, United States
  • Mayo Clinic Cancer Center
    Rochester, Minnesota 55905, United States
  • Mallinckrodt Institute of Radiology at Washington University Medical Center
    Saint Louis, Missouri 63110, United States
  • M.D. Anderson Cancer Center at University of Texas
    Houston, Texas 77030-4009, United States
  • Virginia Commonwealth University Massey Cancer Center
    Richmond, Virginia 23298-0037, United States
09

References and documents

Publications

  • Vanness DJ, Knudsen AB, Lansdorp-Vogelaar I, Rutter CM, Gareen IF, Herman BA, Kuntz KM, Zauber AG, van Ballegooijen M, Feuer EJ, Chen MH, Johnson CD. Comparative economic evaluation of data from the ACRIN National CT Colonography Trial with three cancer intervention and surveillance modeling network microsimulations. Radiology. 2011 Nov;261(2):487-98. doi: 10.1148/radiol.11102411. Epub 2011 Aug 3. PubMed 21813740 ↗
  • Johnson CD, Herman BA, Chen MH, Toledano AY, Heiken JP, Dachman AH, Kuo MD, Menias CO, Siewert B, Cheema JI, Obregon R, Fidler JL, Zimmerman P, Horton KM, Coakley KJ, Iyer RB, Hara AK, Halvorsen RA Jr, Casola G, Yee J, Blevins M, Burgart LJ, Limburg PJ, Gatsonis CA. The National CT Colonography Trial: assessment of accuracy in participants 65 years of age and older. Radiology. 2012 May;263(2):401-8. doi: 10.1148/radiol.12102177. Epub 2012 Feb 23. PubMed 22361006 ↗
  • Hara AK, Blevins M, Chen MH, Dachman AH, Kuo MD, Menias CO, Siewert B, Cheema JI, Obregon RG, Fidler JL, Zimmerman P, Horton KM, Coakley KJ, Iyer RB, Halvorsen RA Jr, Casola G, Yee J, Herman BA, Johnson CD. ACRIN CT colonography trial: does reader's preference for primary two-dimensional versus primary three-dimensional interpretation affect performance? Radiology. 2011 May;259(2):435-41. doi: 10.1148/radiol.11100250. Epub 2011 Mar 1. PubMed 21364081 ↗
  • Hara AK, Kuo MD, Blevins M, Chen MH, Yee J, Dachman A, Menias CO, Siewert B, Cheema JI, Obregon RG, Fidler JL, Zimmerman P, Horton KM, Coakley K, Iyer RB, Halvorsen RA Jr, Casola G, Johnson CD. National CT colonography trial (ACRIN 6664): comparison of three full-laxative bowel preparations in more than 2500 average-risk patients. AJR Am J Roentgenol. 2011 May;196(5):1076-82. doi: 10.2214/AJR.10.4334. PubMed 21512073 ↗
  • Siewert B, Gareen I, Vanness D, et al.: ACRIN 6664: patient acceptance and preferance of CT colonography compared to optical colonoscopy for colon cancer screening. [Abstract] J Clin Oncol 27 (Suppl 15): A-4034, 2009.
  • Johnson CD, Chen MH, Toledano AY, Heiken JP, Dachman A, Kuo MD, Menias CO, Siewert B, Cheema JI, Obregon RG, Fidler JL, Zimmerman P, Horton KM, Coakley K, Iyer RB, Hara AK, Halvorsen RA Jr, Casola G, Yee J, Herman BA, Burgart LJ, Limburg PJ. Accuracy of CT colonography for detection of large adenomas and cancers. N Engl J Med. 2008 Sep 18;359(12):1207-17. doi: 10.1056/NEJMoa0800996. Erratum In: N Engl J Med. 2008 Dec 25;359(26):2853. PubMed 18799557 ↗

Individual participant data

Plan to share: Yes — Researchers may request data from the ACRIN data access committee by reviewing the information at: https://www.acrin.org/RESEARCHERS/POLICIES/DATAANDIMAGESHARINGPOLICY.aspx

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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Dec 22, 2020, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT00084929
Lead sponsor
American College of Radiology Imaging Network
Collaborators
National Cancer Institute (NCI)
Responsible party
Sponsor
First posted
Jun 11, 2004
Start date
Feb 2005
Primary completion
Sep 11, 2007
Completion
May 13, 2010
Results posted
Nov 16, 2020
Last update
Dec 22, 2020

Study contacts

C. Daniel Johnson, MD
study chair · Mayo Clinic

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Nov 2020. You cannot join it, but the record below documents what was studied.

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