Faculty Bibliography

PURPOSE: To compare thin-section multi-detector row computed tomographic (CT) colonography with conventional colonoscopy in the evaluation of colorectal polyps and cancer in asymptomatic average-risk patients. MATERIALS AND METHODS: Sixty-eight asymptomatic men (age > 50 years) scheduled to undergo screening colonoscopy were enrolled in this study. CT colonography was followed by conventional colonoscopy, performed on the same day. Supine and prone CT colonography were performed after colonic insufflation with room air. A gastroenterologist measured all polyps, which were categorized as 1-5, 6-9, or over 10 mm. Biopsy and histologic evaluation were performed of all polyps. CT colonography and colonoscopy results were compared for location, size, and morphology of detected lesions. Point estimates and 95% CIs were provided for specificity and sensitivity of CT by using results at conventional colonoscopy as the reference standard. RESULTS: At colonoscopy, 98 polyps were identified in 39 patients; 21 (21.4%) of 98 were detected at CT colonography. Sensitivity was 11.5% (nine of 78) for polyps 1-5 mm, 52.9% (nine of 17) for polyps 6-9 mm, and 100% (three of three) for polyps over 10 mm. Results at colonoscopy were normal in 29 (42.6%) of 68 patients; at CT colonography, results were correctly identified as normal in 26 of these 29 patients. In one of these patients, a lesion larger than 10 mm was detected at CT colonography. The per-patient specificity of CT was 89.7% (26 of 29; 95% CI: 72.7%, 97.8%). The mean time for CT image interpretation was 9 minutes. CONCLUSION: In patients at average risk for colorectal cancer, CT colonography is a sensitive and specific screening test for detecting polyps 10 mm or larger; the sensitivity for detecting smaller polyps is decreased. Examination findings can be interpreted in a clinically feasible amount of time

BACKGROUND: Testing stool for occult blood at the time of digital rectal examination (DRE) has been discouraged because it is thought to increase the number of false-positive test results. OBJECTIVE: To compare the diagnostic yield of colonoscopy and the cost per cancer detected in asymptomatic patients with a positive fecal occult blood test result obtained by DRE with that obtained from spontaneously passed stool (SPS) samples. METHODS: We reviewed the medical records of consecutive asymptomatic patients at average risk for colorectal cancer who were referred for colonoscopy to evaluate a positive fecal occult blood test result obtained by DRE (n = 282) or SPS samples (n = 390). The cost of colonoscopy was estimated by adding the physician fee under Medicaid reimbursement, the facility fee for endoscopy, and the pathology fee for the biopsy specimens. RESULTS: During the 5-year study period, 672 patients were evaluated and a colonic source of occult bleeding was identified in 145 patients (21.6%). The predictive value of a positive fecal occult blood test result (22.0% vs 21.3%, P = .85) and the cost per cancer detected ($7604.80 vs $7814.54) were no different in the DRE and SPS groups, with carcinomas being detected in 11.7% and 11.3% of patients, respectively. CONCLUSIONS: Testing stool for occult blood at the time of DRE does not increase the number of false-positive test results or the cost per cancer detected in asymptomatic patients at average risk for colorectal cancer. In this patient population, all individuals should be evaluated by full colonoscopy regardless of the method of stool collection

PURPOSE: There are no recommendations as to whether endoscopic evaluation of the upper gastrointestinal tract is indicated in asymptomatic patients who have a positive fecal occult blood test and a negative colonoscopy. SUBJECTS AND METHODS: All asymptomatic patients with a positive fecal occult blood test who were referred for diagnostic endoscopy were identified. Patient charts, endoscopy records, and pathology reports were reviewed. RESULTS: During the 5-year study period, 498 asymptomatic patients with a positive fecal occult blood test and negative colonoscopy were evaluated. An upper gastrointestinal source of occult bleeding was detected in 67 patients (13%), with peptic ulcer disease being the most common lesion identified (8%). Four patients were diagnosed with gastric cancer and 1 had esophageal carcinoma. In addition, 74 patients (15%) had lesions that were not considered a source of occult bleeding; these findings prompted a change in management in 56 patients (11%). Anemia was the only variable significantly associated with having a clinically important lesion identified (multivariate odds ratio = 5.0; 95% confidence interval 2.9 to 8.5; P <0.001). CONCLUSIONS: Upper gastrointestinal endoscopy yields important findings in asymptomatic patients with a positive fecal occult blood test and negative colonoscopy. Our data suggest that endoscopic evaluation of the upper gastrointestinal tract should be considered, especially in patients with anemia

The hepatitis C virus (HCV) and the human immunodeficiency virus (HIV) often co-infect the same individuals because they share comparable routes of transmission. Co-infection with HIV in those patients infected with HCV influences the accuracy of HCV diagnostic testing, levels of HCV viremia, severity of liver histopathology, and rate of progression to cirrhosis. By contrast, the effect of HCV co-infection on HIV disease is unclear. Nevertheless, the combination therapy containing recombinant interferon alfa-2b (rIFN-alpha 2b) plus ribavirin has been shown to be efficacious in the treatment of chronic hepatitis C, whereas alpha interferon monotherapy has been shown to be efficacious in patients co-infected with HCV and HIV. It is therefore logical to propose and test the hypothesis that combination rIFN-alpha 2b/ribavirin therapy will also benefit patients who are co-infected with HCV and HIV. A double-blind, placebo-controlled study is presently under way to investigate this hypothesis