Efficacy of Second Forward-view Examination of Left Colon for Adenoma Detection During Colonoscopy

Study Overview
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Brief Summary
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The incidence of colorectal cancer in China is increasing year by year. Studies have shown that colorectal cancer is more common in the left colon，especially in the China. Our previous study also showed a higher rate of missed adenoma in the left colon than the right colon during colonoscopy. Additionally, prolonging withdrawal time could only improve the ADR of right colon, but had limited effect on the ADR of left colon in our previous research. Our aim is to evaluate the effect of a second forward view examination of the left colon on the detection of adenoma detection during colonoscopy.

Official Title
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Efficacy of Second Forward-view Examination of Left Colon for Adenoma Detection During Colonoscopy: a Multicenter, Prospective, Randomized Controlled Trial

Conditions
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Colon Adenoma

Intervention / Treatment
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* Behavioral: re-examination
* Behavioral: extended withdraw time


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients whose age are between 40-75, or aged 76-85 depending on his condition Patients who have indications for screening Patients who have signed inform consent form. Exclusion Criteria: Patients who have undergone colonic resection Patients with alarming signs and symptoms of colorectal cancer: hematochezia, melena, anemia, weight loss, abdominal mass, positive digital rectal examination Patients with abnormal blood coagulation or taking antiplatelets or anticoagulants within 7 days before colonoscopy Patients with inflammatory bowel diseases Patients with a history of abdominal surgery, or highly suspected or confirmed colorectal cancers by radiographic and laboratory tests Patients with hereditary colorectal cancer syndrome (including familial adenomatous polyposis). Patients with pregnancy, severe chronic cardiopulmonary and renal disease. Patients with failed cecal intubation Patients with poor BPQ that necessitated a second bowel preparation Patients with therapeutic colonoscopy for existing lesions Patients refusing to participate or to provide informed consent

Ages Eligible for Study
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Minimum Age: 45 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Second forward view examination group<br>After successful intubation of the cecum, the colonoscope is withdrawn to the splenic curvature with the colonic mucosa carefully inspected. Then the left colon, including the splenic curvature to the anus, is examined twice in the forward view. | Behavioral: re-examination<br>* During colonoscopy, the left colon was examined a second time in the forward view.<br>|
| Experimental: Extended withdrawal time group<br>After successful intubation of the cecum, the colonoscope is withdrawn to the splenic curvature with the colonic mucosa carefully inspected. The colonoscope was withdrawn to the anus directly with withdrawal time extended to the double routine withdrawal time of the left colon. | Behavioral: extended withdraw time<br>* During colonoscopy, the left colon was examined with double basic withdrawal time in the forward view.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Left colon adenoma detection rate (LCADR) | LCADR is the number of patients with at least one adenoma in the left colon, divided by the total number of patients. | 60 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| adenoma detection rate(ADR) | ADR is the number of patients with at least one adenoma, divided by the total number of patients. | 60 minutes | 
| left colon adenomas per colonoscopy (LCAPC) | LCAPC was calculated as the number of adenomas detected during in left colon colonoscopy withdraw divided by the number of colonoscopies. | 60 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Adenoma detection rate, colonoscopy