Colon cancer is one of the leading causes of cancer deaths in the United States. However, most colon cancers can be prevented if precursor colonic polyps are detected and removed. An advanced ...computer-aided diagnosis (CAD) scheme was developed for the automated detection of polyps at computed tomographic (CT) colonography. A region encompassing the colonic wall is extracted from an isotropic volume data set obtained by interpolating CT colonographic scans along the axial direction. Polyp candidates are detected with computation of three-dimensional (3D) geometric features that characterize polyps, followed by extraction of polyps with hysteresis thresholding and fuzzy clustering using these geometric features. The number of false-positive findings is reduced by extracting 3D texture features from polyp candidates and applying quadratic discriminant analysis to the candidates. This CAD scheme was applied in 71 patients who underwent CT colonography, 14 of whom had colonoscopically confirmed polyps (n = 21). At by-patient analysis, sensitivity was 100%, with an average false-positive rate of 2.0 per patient. At by-polyp analysis, the scheme detected 90% of the polyps at the same false-positive rate. This CAD scheme permits accurate detection of suspicious lesions and thus has the potential to reduce radiologists' interpretation time and improve their diagnostic accuracy in the detection of polyps at CT colonography.
Joseph Barnett Kirsner, MD, PhD Hanauer, Stephen B; Rubin, David T
Gastroenterology (New York, N.Y. 1943),
11/2012, Letnik:
143, Številka:
5
Journal Article
Background:
Pivotal trials for adalimumab (ADA) demonstrated effectiveness versus placebo for induction and maintenance of remission in moderate to severely active Crohn's disease (CD). Although the ...approved maintenance regimen in the U.S. is 40 mg subcutaneously every 14 days, some patients require dose‐escalation (DE either an increase in the delivered dose or decrease in the interval of treatment). Our objective was to determine which patient‐, disease‐, and therapy‐related factors were associated with DE in CD patients treated with ADA.
Methods:
This retrospective medical record review of patients included all patients treated with ADA for CD at the University of Chicago Inflammatory Bowel Disease Center between 2003 and 2008. Patient‐related factors, disease‐related factors, and therapy‐related factors were analyzed. Survival and logistic regression analyses were performed.
Results:
In all, 75 patients treated with ADA between December 2003 and June 2008 were identified. Thirty‐one subjects (41%) required DE (32% male, median age 37.6, median disease duration 22.7 years) after a median 20 weeks of therapy (range 2–75). Patient‐, clinical‐, and therapy‐related factors were similar between DE and non‐DE. Need for DE was predicted by a family history of inflammatory bowel disease (IBD) (P = 0.0187). Time to DE was predicted by male gender, isolated colonic disease, and smoking history (all P < 0.05); however, only male gender was an independent predictor of time to DE.
Conclusions:
In all, 41% of CD patients required ADA DE, with shorter time to DE in smokers, men, and patients with isolated colonic disease. Patients, caregivers, and insurers should anticipate DE when utilizing ADA in CD. (Inflamm Bowel Dis 2011;)
Background:
If dysplasia is found on biopsies during surveillance colonoscopy for ulcerative colitis (UC), many experts recommend colectomy given the substantial risk of synchronous colon cancer. The ...objective was to learn if UC patients' perceptions of their colon cancer risk and if their preferences for elective colectomy match with physicians' recommendations if dysplasia was found.
Methods:
A self‐administered written survey included 199 patients with UC for at least 8 years (mean age 49 years, 52% female) who were recruited from Dartmouth‐Hitchcock (n = 104) and the University of Chicago (n = 95). The main outcome was the proportion of patients who disagree with physicians' recommendations for colectomy because of dysplasia.
Results:
Almost all respondents recognized that UC raised their chance of getting colon cancer. In all, 74% thought it was “unlikely” or “very unlikely” to get colon cancer within the next 10 years and they quantified this risk to be 23%; 60% of patients would refuse a physician's recommendation for elective colectomy if dysplasia was detected, despite being told that they had a 20% risk of having cancer now. On average, these patients would only agree to colectomy if their risk of colon cancer “right now” were at least 73%.
Conclusions:
UC patients recognize their increased risk of colon cancer and undergo frequent surveillance to reduce their risk. Nonetheless, few seem prepared to follow standard recommendations for elective colectomy if dysplasia is found. This may reflect the belief that surveillance alone is sufficient to reduce their colon cancer risk or genuine disagreement about when it is worth undergoing colectomy. Inflamm Bowel Dis 2010
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