Although some studies have shown that the quantitative, immunochemical fecal occult blood test (FOBT) (qFIT) has better performance characteristics than the standard guaiac-based FOBT (GT) for identifying advanced colorectal neoplasia (ACRN), there is limited information on test performance of these tests in average-risk populations. Seven hundred seventy consecutive average-risk patients from four centers who were undergoing screening colonoscopy also provided stool samples. Stool specimens from three consecutive bowel movements were applied to a hemoccult II test card (Beckman Coulter, Fullerton, CA) and OC-SENSA MICRO (Eiken Chemical, Tokyo, Japan) sampling probes at the same time. We measured the diagnostic value of the qFIT for detecting an ACRN by using three criteria: sensitivity, specificity, and likelihood ratios. A receiver operating characteristic curve for determining the qFIT cutoff values and the number of tests that best discriminated between ACRNs and other findings were determined. Seventy-eight ACRNs were identified during colonoscopy. At all hemoglobin thresholds, the sensitivity of the qFIT was higher than that of the GT for cancer or ACRN. The sensitivity and specificity of the GT for detecting advanced adenomas, cancer, and ACRNs were 13.6%/92.4%, 30.8%/92.4%, and 16.7%/92.9%, respectively. Using the 100 ng/ml cut point and three-sample qFIT results, the sensitivity and specificity of the qFIT for detecting advanced adenomas, cancer, and ACRNs were 33.9%/90.6%, 84.6%/89.8%, and 43.7%/91.9%, respectively. The area under the curve for cancer indicated that using either 2 or 3 tests provided the best discrimination for cancer. The qFIT provides a higher sensitivity for detecting ACRN and cancer than the GT, and has an acceptable specificity that significantly reduces the need for colonoscopic evaluation in the screened population.
1 October 2013 in American Journal of Gastroenterology
There are few data on cold snare polypectomy (CSP) in direct comparison with cold forceps polypectomy (CFP) for colonoscopic resection of diminutive colorectal polyps (DCPs; ≤5 mm). The primary aim of this study was to compare the histologic polyp eradication rate of CSP with that of CFP using double-biopsy technique. This was a randomized controlled trial at a single academic hospital. Of the 165 patients invited, 54 consecutive patients having 117 eligible polyps were enrolled in this study. To evaluate histologic eradication of polyps, two or more additional biopsies were taken from the base and edges of the polypectomy site. The mean size of polyps was 3.66 mm (±1.13). Most polyps evaluated were tubular adenomas (69.9%). The rate of histologic eradication was significantly higher in the CSP group than in the CFP group (93.2% vs. 75.9%, P=0.009). The time taken for polypectomy was significantly shorter in the CSP group (14.29 vs. 22.03 s, P<0.001). Failure of tissue retrieval was noted in 6.8% of polyps resected by CSP. Multivariate analysis revealed that the method of polypectomy (CFP) and the polyp size (≥4 mm) were independent predictors associated with incomplete histologic eradication (odds ratio (OR) 4.750 (95% confidence interval (CI): 1.459–15.466), OR 4.375 (95% CI: 1.345–14.235); all P<0.05, respectively). CSP is superior to CFP for the endoscopic removal of DCPs with regard to completeness of polypectomy. CSP technique should be considered the primary method for endoscopic treatment of polyps in the 4–5-mm size range (ClinicalTrials.gov number: NCT01646242).