Trial document

This trial has been registered retrospectively.
drksid header


Trial Description

start of 1:1-Block title


Chromoendoscopy vs. standard endoscopy for detection of colon adenomas

end of 1:1-Block title
start of 1:1-Block acronym

Trial Acronym


end of 1:1-Block acronym
start of 1:1-Block url

URL of the Trial


end of 1:1-Block url
start of 1:1-Block public summary

Brief Summary in Lay Language

Colonic cancer arises from precursors the so called adenomas. Removal of adenomas during screening colonoscopy can effectively prevent colonic cancer. Unfortunately in many cases colonoscopy does not detect all adenomas. To improve efficiency of adenoma detection spraying of dye within the colon (chromoendoscopy) was proposed to increase the mucosal surface contrast. However, it is yet unclear if this technique shows an additional benefit. In the present study adenoma detection using colonoscopy with chromoendoscopy is compared to standard colonoscopy

end of 1:1-Block public summary
start of 1:1-Block scientific synopsis

Brief Summary in Scientific Language

Colonoscopy is considered the gold standard for screening for colorectal neoplasias. Detection of adenomas at colonoscopy is of utmost importance since endoscopic resection of these neoplastic lesions has been shown to effectively prevent colorectal cancer. Unfortunately, at standard colonoscopy substantial percentage (10-15 %) of adenomas are missed during the procedure, even by experienced practitioners. Low mucosal contrast might contribute to the miss rate of small and flat lesions that show only subtle changes in mucosal topography. In this context chromoscopy with indigocarmine dye application with a spraying catheter was proposed for enhancement of the mucosal surface. While 3 studies indicate that chromoendoscopy might increase detection rates of small and flat adenomas in diagnostic colonoscopies one trial did not find any overall difference in the adenoma yield achieved by chromoendoscopy. However, the sample size of these studies was limited and the design was monocentric.
The present study investigated the value of indigocarmine panchromoendoscopy for detection of colonic polyps and compared its performance with that of standard colonoscopy. It represents the first prospective randomized multicenter trial on this topic.

end of 1:1-Block scientific synopsis
start of 1:1-Block organizational data

Organizational Data

  •   DRKS00000174
  •   2009/07/24
  •   [---]*
  •   yes
  •   Approved
  •   Nr. 84/2007, Ethikkommission der Landesärztekammer Hessen
end of 1:1-Block organizational data
start of 1:n-Block secondary IDs

Secondary IDs

  • [---]*
end of 1:n-Block secondary IDs
start of 1:N-Block indications

Health Condition or Problem studied

  •   recommended screening colonoscopy or diagnostic colonoscopy
end of 1:N-Block indications
start of 1:N-Block interventions

Interventions/Observational Groups

  •   Group 1 (control group):
    Screening colonoscopy or diagnostic colonosciopy is performed. When the cecum is inserted patients are randomly assigned to conventional colonoscopy (control group) or chromoendoscopy with indigocarmine spraying.
    Group allocation of patients is performed by dedicated nurses using standard randomization lists. These lists contain consecutive patient numbers and each number is linked to allocation to one of the two study arms. Randomization lists are not accessible for endoscopists. Assessment of the colon to search for lesions was systematically performed only during withdrawal of the instrument with a minimum diagnostic extubation time that was set at six minutes. Patients randomized to the control group received withdrawal with conventional colonoscopy . In both groups morphology and anatomical location of detected lesions were documented during withdrawal. Importantly, histology of the detected lesion was predicted and documented by the endoscopist. .
  •   In the chromoendoscopy group, withdrawal was performed using the indigo carmine low-volume spraying technique. A dye-spraying catheter (PW-5L-1, Olympus) was inserted through the colonoscope’s working channel and was extended 5–10 mm from the instrument channel throughout extubation, allowing straightening of mucosal folds for inspection of the proximal side and aspiration of excess fluid.
    During continuous extubation, indigo carmine (0.2%) was gently applied by the nurse in order to achieve diffuse coverage of the entire mucosal surface, using only a small volume of dye in order to avoid excess dye accumulation. This continuous one-step low-volume technique is much simpler than the previously described multiple-step staining techniques involving segmental staining followed by reexamination after excess dye has been aspirated.
end of 1:N-Block interventions
start of 1:1-Block design


  •   Interventional
  •   [---]*
  •   Randomized controlled trial
  •   Open (masking not used)
  •   [---]*
  •   Active control
  •   Prevention
  •   Parallel
  •   N/A
  •   [---]*
end of 1:1-Block design
start of 1:1-Block primary endpoint

Primary Outcome

Primary endpoint is the number of adenoma bearing patients who are detected with the different techniques

end of 1:1-Block primary endpoint
start of 1:1-Block secondary endpoint

Secondary Outcome

The total number of adenomas in both study groups || accuracy of histology prediction of lesions by the endoscopist

end of 1:1-Block secondary endpoint
start of 1:n-Block recruitment countries

Countries of Recruitment

  •   Germany
end of 1:n-Block recruitment countries
start of 1:n-Block recruitment locations

Locations of Recruitment

  • [---]*
end of 1:n-Block recruitment locations
start of 1:1-Block recruitment


  •   Actual
  •   2008/07/01
  •   1000
  •   Multicenter trial
  •   National
end of 1:1-Block recruitment
start of 1:1-Block inclusion criteria

Inclusion Criteria

  •   Both, male and female
  •   45   Years
  •   no maximum age
end of 1:1-Block inclusion criteria
start of 1:1-Block inclusion criteria add

Additional Inclusion Criteria

patients presenting for screening or diagnostic colonoscopy

end of 1:1-Block inclusion criteria add
start of 1:1-Block exclusion criteria

Exclusion Criteria

known colonic polyps in situ,
known inflammatory bowel disease,
overt bleeding,
polyposis syndrome,
previous surgical resection of the colon,
patients receiving anticoagulant medication,
patients without informed written consent before

end of 1:1-Block exclusion criteria
start of 1:n-Block addresses


  • start of 1:1-Block address primary-sponsor
    • Dr. Horst-Schmidt-Klinik Wiesbaden
    • Mr.  Prof. Dr. med.  Christian  Ell 
    • Ludwig-Erhard-Str. 100
    • 65 199  Wiesbaden
    • Germany
    end of 1:1-Block address primary-sponsor
    start of 1:1-Block address contact primary-sponsor
    end of 1:1-Block address contact primary-sponsor
  • start of 1:1-Block address scientific-contact
    • Dr. Horst-Schmidt-Klinik Wiesbaden
    • Mr.  Dr. med.  Jürgen  Pohl 
    • Ludwig-Erhard-Str. 100
    • 65199  Wiesbaden
    • Germany
    end of 1:1-Block address scientific-contact
    start of 1:1-Block address contact scientific-contact
    end of 1:1-Block address contact scientific-contact
  • start of 1:1-Block address public-contact
    • Dr. Horst-Schmidt-Klinik Wiesbaden
    • Mr.  Dr. med.  Jürgen  Pohl 
    • Ludwig-Erhard-Str. 100
    • 665199  Wiesbaden
    • Germany
    end of 1:1-Block address public-contact
    start of 1:1-Block address contact public-contact
    end of 1:1-Block address contact public-contact
end of 1:n-Block addresses
start of 1:n-Block material support

Sources of Monetary or Material Support

  • start of 1:1-Block address materialSupport
    • Dr.Horst-Schmidt-Klinik Wiesbaden
    • Mr.  Prof. Dr.  Christian  Ell 
    • Ludwig-Erhard-Str. 100
    • 65199  Wiesbaden
    • Germany
    end of 1:1-Block address materialSupport
    start of 1:1-Block address contact materialSupport
    end of 1:1-Block address contact materialSupport
end of 1:n-Block material support
start of 1:1-Block state


  •   Recruiting complete, follow-up complete
  •   2010/03/01
end of 1:1-Block state
start of 1:n-Block publications

Trial Publications, Results and other Documents

  • [---]*
end of 1:n-Block publications
* This entry means the parameter is not applicable or has not been set.