Ramón Angós

Use of colonoscopy as a primary screening test for colorectal cancer in average risk people

OBJECTIVE:The use of colonoscopy as a primary screening test for colorectal cancer (CRC) in average risk adults is a subject of controversy. Our primary objective was to build a predictive model based on a few simple variables that could be used as a guide for identifying average risk adults more suitable for examination with colonoscopy as a primary screening test.METHODS:The prevalence of advanced adenomas was assessed by primary screening colonoscopy in 2210 consecutive adults at least 40 yr old, without known risk factors for CRC. Age, gender, and clinical and biochemical data were compared among people without adenomas, those with nonadvanced adenomas, and those with any advanced neoplasm. A combined score to assess the risk of advanced adenomas was built with the variables selected by multiple logistic regression analysis.RESULTS:Neoplastic lesions were found in 617 subjects (27.9%), including 259 with at least one neoplasm that was 10 mm or larger, villous, or with moderate-to-severe dysplasia, and 11 with invasive cancers. Advanced lesions were more frequent among men, older people, and those with a higher body mass index (BMI). These three variables were independent predictors of advanced adenomas in multivariate analysis. A score combining age, sex, and BMI was developed as a guide for identifying individuals more suitable for screening colonoscopy.CONCLUSIONS:Age, gender, and BMI can be used to build a simple score to select those average risk adults who might be candidates for primary screening colonoscopy.

Gastroduodenal Injury After Radioembolization of Hepatic Tumors

BACKGROUND:Radioembolization is a new tool for the treatment of hepatic tumors that consists in the injection of biocompatible microspheres carrying radioisotopes into the hepatic artery or its branches.METHODS:We have performed radioembolization in 78 patients with hepatic tumors using resin-based microspheres loaded with yttrium-90. All patients were previously evaluated to minimize the risk of hazardous irradiation to nontarget organs and to obtain the data needed for dose calculation.RESULTS:We report a complication found in three cases (3.8%) that consists of abdominal pain resulting from gastroduodenal lesions and that had a chronic, insidious course. Microscopically, microspheres were detected in the specimens obtained from all affected gastric areas. Since these gastroduodenal lesions do not appear when nonradiating microspheres are injected in animals, lesions are likely to be due to radiation and not to an ischemic effect of vascular occlusion by spheres.CONCLUSIONS:We believe that a pretreatment evaluation that includes a more thorough scrutiny of the hepatic vascularization in search of small collaterals connecting to the gastroduodenal tract can help prevent this awkward complication.

Diagnostic value of distal colonic polyps for prediction of advanced proximal neoplasia in an average-risk population undergoing screening colonoscopy

BACKGROUND For colorectal cancer screening, the predictive value of distal findings in the ascertainment of proximal lesions is not fully established. The aims of this study were to assess distal findings as predictors of advanced proximal neoplasia and to compare the predictive value of endoscopy alone vs. combined endoscopic and histopathologic data. METHODS Primary colonoscopy screening was performed in 2210 consecutive, average-risk adults. Age, gender, endoscopic (size, number of polyps), and histopathologic distal findings were used as potential predictors of advanced proximal neoplasms (i.e., any adenoma > or =1 cm in size, and/or with villous histology, and/or with severe dysplasia or invasive cancer). Polyps were defined as distal if located in the descending colon, the sigmoid colon, or the rectum. Those in other locations were designated proximal. RESULTS Neoplastic lesions, including 11 invasive cancers, were found in 617 (27.9%) patients. Advanced proximal neoplasms without any distal adenoma were present in 1.3% of patients. Of the advanced proximal lesions, 39% were not associated with any distal polyp. Older age, male gender, and distal adenoma were independent predictors of advanced proximal neoplasms. The predictive ability of a model with endoscopic data alone did not improve after inclusion of histopathologic data. In multivariate logistic regression analysis, the predictive ability of models that use age, gender, and any combination of distal findings was relatively low. The proportion of advanced proximal neoplasms identified if any distal polyp was an indication for colonoscopy was only 62%. CONCLUSIONS A strategy in which colonoscopy is performed solely in patients with distal colonic findings is not effective screening for the detection of advanced proximal neoplasms in an average-risk population.

⁎4500 Prevalence and risk factors of advanced colonic adenomas in average-risk population.

Evidence from controlled trials suggest that removing adenomatous polyps reduce the incidence of colorectal cancer. Nowadays, it is clear that only a small proportion of adenomas go on to develop into cancer. Advanced adenomas (AA; adenoma ≥ 1 cm in size, with villous component, or with moderate to high-grade dysplasia) are associated with an increased risk of malignancy. Aims: To establish independent predictive factors of AA in average-risk asymptomatic population. Methods: From 1988 to 1998 screening total colonoscopy was performed, as a part of a routine medical checking, in 2210 consecutive average-risk asymptomatic people, in whom strict exclusion criteria were applied. Clinical, biochemical, endoscopic and histologic data were recorded. Univariate comparisons were assessed using the Chi2 test and logistic regression. Backward stepwise logistic regression was used for multivariate analysis. Results: Colonic polyps were detected in 885 of 2210 patients and neoplastic lesions in 617 (27.9%). 11 subjects (0.5%) presented malignant polyps or carcinoma. AA were found in 268 patients (12.1%). The variables selected by univariate analyses to enter the multivariate model were: age (p

4503 Prevalence and risk factors for advanced proximal colonic adenomas in average-risk population.

Aims: To establish independent predictive risk factors for APA in averagerisk population. Methods: From 1988 to 1998 screening total colonoscopy was performed in consecutive average-risk people, with strict exclusion criteria. Clinical, biochemical, endoscopic and histologic data were recorded. The term advanced was used for adenomas with villous component, moderate-severe dysplasia or ≥1cm. Adenomas were defined as distal if they came from the descending colon or distally. Univariate comparisons were assesed using the Chi2 Test and logistic regression. Backward stepwise logistic regression was used for multivariate analyses. Results: APA were detected in 125 of 2210 subjects (5.66%); 56 (44.8%) had no index distal adenoma. Independent predictors for presenting APA, after adjustment for the endoscopist who performed the endoscopy, are shown in the table. Conclusions: Almost half cases with APA did not present a distal index lesion. Distal polyp characteristics which were independent risk factors for APA were villous component and moderate-severe dysplasia.This multivariate model offers guidelines for clinicians in the approach to patients with distal tubular adenomas.