Complete Histologic Resection of Adenomatous Polyps? (Complete Adenoma REsection Trial - CARE Trial)
All patients who present for a colonoscopy and meet inclusion and exclusion criteria will be
asked to participate, and all patients with resectable polyps will be included. See also
inclusion and exclusion criteria.
All patients will have undergone a regular bowel preparation with polyethylene glycol lavage
with 4-6 L until clear rectal fluid is evacuated.
Polyp resection will be performed by experienced endoscopists (each with over 500
colonoscopies performed). All polyps between 5 and 20mm will be removed with an
electro-cautery snare. Polyp size will be estimated using the snare catheter (2.5mm) or the
snare diameter (10x20mm, 15x30mm, 20x20mm) before resection. The endoscopist will grade the
difficulty of resection. Following the resection, the endoscopist will closely examine the
resection margins. Biopsies will be taken from resection margins: 2 biopsies will be
obtained from opposite margins for polyps 5-9mm, and 4 biopsies will be taken for polyps
10-20mm from all four quadrants of the resection margins. In case of assumed incomplete
resection this will be documented and further (piecemeal) resections should be done, if this
is not feasible, margins can be cauterized according to standard polypectomy resection (e.g.
by argon beamer coagulation) after previous biopsy. Only those polyps that are found to be
adenomatous polyps will be included in the analysis.
If polyp resection is complicated by bleeding (not self-sustained), no biopsies will be
taken and any additional polyps that will be found during the remaining examination will be
excluded from analysis. Any bleeding from the margins after polypectomy will be treated by
endoscopic injection using diluted epinephrine (1:10.000).
A single research subject may have many eligible polyps. To avoid taking many biopsies, the
investigators will not include more than 5 eligible polyps (the first 5 that are detected)
per patient in the study.
Polyps and biopsies will be sent to the pathology lab of each center. The polyps will be
evaluated according to common practice. In addition information regarding resection margins
will be provided for each polyp: R0= free of adenomatous tissue, R1=adenomatous tissue
detected in the margin. This information is not routinely provided by the pathologist as
there is so far no data whether this information is reliable. Only adenomatous polyps will
be included in the analysis. Hyperplastic polyps will not be included. Biopsies will only be
processed after the diagnosis of an adenomatous polyp was made. Biopsies will be evaluated
for presence of adenomatous tissue. The additional impact for the pathology lab includes a)
processing of biopsies belonging to the polyp specimens, and b) providing information on
polyp margins. The VA pathology lab estimated the financial impact to be low and there will
be no financial requests. The pathological diagnosis, including the reading of the biopsies,
will become part of the medical record. If biopsies contain adenomatous tissue the patient
will be ask to return for a follow-up colonoscopy within 1 year. This is within current
standard of care to repeat a colonoscopy to assure complete adenoma resection.
Observational Model: Case-Only, Time Perspective: Prospective
• Proportion of remaining adenomatous tissue after adenoma resection of all sessile polyps between 5 and 20mm.
Heiko Pohl, MD
White River Junction VAMC, Dartmouth Medical School
United States: Federal Government
|Dartmouth Hitchcock Medical Center||Lebanon, New Hampshire 03756|
|White River Junction VAMC||White River Junction, Vermont 05009-001|