Colorectal cancer(CRC) is the 2^(nd) most common cancer in women and 3^(rd) most common cancer in men worldwide. Most CRCs develop from adenomatous polyps arising from glandular epithelium. Tumor growth is initiated b...Colorectal cancer(CRC) is the 2^(nd) most common cancer in women and 3^(rd) most common cancer in men worldwide. Most CRCs develop from adenomatous polyps arising from glandular epithelium. Tumor growth is initiated by mutation of the tumor suppressor gene APC and involves other genetic mutations in a stepwise process over years. Both hereditary and environmental factors contribute to the development of CRC. Screening has been proven to reduce the incidence of CRC. Screening has also contributed to the decrease in CRC mortality in the United States. However,CRC incidence and/or mortality remain on the rise in some parts of the world(Eastern Europe,Asia,and South America),likely due to factors including westernized diet,lifestyle,and lack of healthcare infrastructure. Multiple screening options are available,ranging from direct radiologic or endoscopic visualization tests that primarily detect premalignant or malignant lesions such as flexible sigmoidoscopy,optical colonoscopy,colon capsule endoscopy,computed tomographic colonography,and double contrast barium enema- to stool based tests which primarily detect cancers,including fecal DNA,fecal immunochemical test,and fecal occult blood test. The availability of some of these tests is limited to areas with high economic resources. This article will discuss CRC epidemiology,pathogenesis,risk factors,and screening modalities with a particular focus on new technologies.展开更多
AIM:To evaluate the efficacy of reduced cathartic bowel preparation with 2 L polyethylene glycol(PEG)-4000 electrolyte solution and 10 mg bisacodyl enteric-coated tablets for computed tomographic colonography(CTC).MET...AIM:To evaluate the efficacy of reduced cathartic bowel preparation with 2 L polyethylene glycol(PEG)-4000 electrolyte solution and 10 mg bisacodyl enteric-coated tablets for computed tomographic colonography(CTC).METHODS:Sixty subjects who gave informed consent were randomly assigned to study group A,study group B or the control group.On the day prior to CTC,subjects in study group A were given 20 mL 40% wt/vol barium sulfate suspension before 3 mealtimes,60 mL 60% diatrizoate meglumine diluted in 250 mL water after supper,and 10 mg bisacodyl enteric-coated tablets 1 h before oral administration of 2 L PEG-4000 electrolyte solution.Subjects in study group B were treated identically to those in study group A,with the exception of bisacodyl which was given 1 h after oral PEG-4000.Subjects in the control group were managed using the same strategy as the subjects in study group A,but without administration of bisacodyl.Residual stool and fluid scores,the attenuation value of residual fluid,and discomfort during bowel preparation in the three groups were analyzed statistically.RESULTS:The mean scores for residual stool and fluid in study group A were lower than those in study group B,but the differences were not statistically significant.Subjects in study group A showed greater stool and fluid cleansing ability than the subjects in study group B.The mean scores for residual stool and fluid in study groups A and B were lower than those in the control group,and were significantly different.There was no significant difference in the mean attenuation value of residual fluid between study group A,study group B and the control group.The total discomfort index during bowel preparation was 46,45 and 45 in the three groups,respectively,with no significant difference.CONCLUSION:Administration of 10 mg bisacodyl enteric-coated tablets prior to or after oral administration of 2 L PEG-4000 electrolyte solution enhances stool and fluid cleansing ability,and has no impact on the attenuation value of residual fluid or the discomfort展开更多
Computed tomographic colonography (CTC) is a promising emerging technology for imaging of the colon. This concise review discusses the currently available data on CTC technique,test characteristics,acceptance,safety,c...Computed tomographic colonography (CTC) is a promising emerging technology for imaging of the colon. This concise review discusses the currently available data on CTC technique,test characteristics,acceptance,safety,cost-effectiveness,follow-up strategy,and extracolonic findings. In summary,CTC technique is still evolving,and further research is needed to clarify the role of automated colonic insufflation,smooth-muscle relaxants,intravenous and oral contrast,soft-ware rendering,and patient positioning. Currently,full bowel preparation is still required to achieve optimal results. The sensitivity for detecting large polyps (> 1 cm) can be as high as 85%,with specificity of up to 97%. These test characteristics are almost comparable to those of conventional colonoscopy. Patient acceptance of CTC is generally higher than that for colonoscopy,especially in patients who have never undergone either procedure. CTC is generally safe,although uncommon instances of colonic perforation have been documented. In terms of cost-effectiveness,most decision analyses have concluded that CTC would only be cost-effective if it were considerably cheaper than conventional colonoscopy. The proper follow-up strategy for small polyps or incidental extracolonic findings discovered during CTC is still under debate. At present,the exact clinical role of virtual colonoscopy still awaits determination. Even though widespread CTC screening is not available today,in the future there may eventually be a role for this technology. Technological advances in this area will undoubtedly continue,with multi-detector row CT scanners allowing thinner collimation and higher reso-lution images. Stool-tagging techniques are likely to evolve and may eventually allow for low-preparation CTC. Perceptual and fatigue-related reading errors can potentially be minimized with the help of computer-aided detection software. Further research will define the exact role of this promising technology in our diagnostic armamentarium.展开更多
AIM:To investigate the perceived impact of computed tomographic colonography(CTC) on endoscopists' current and future practice.METHODS:A 21-question survey was mailed to 1570 randomly chosen American Society for G...AIM:To investigate the perceived impact of computed tomographic colonography(CTC) on endoscopists' current and future practice.METHODS:A 21-question survey was mailed to 1570 randomly chosen American Society for Gastrointestinal Endoscopy(ASGE) members.Participants reported socio-demographics,colonoscopy volume,percentage of colonoscopies performed for screening,and likelihood of integration of CTC into their practice.RESULTS:A total of 367 ASGE members(23%) returned the questionnaire.Respondents were predominantly male(> 90%) and white(83%) with an average age of 49 years.Most respondents(58%) had no plans to incorporate CTC into daily practice and only 7% had already incorporated CTC into daily practice.Private practice respondents were the least likely to incorporate this modality into their daily practice(P=0.047).Forty-three percent of participants were willing to take courses on CTC reading,particularly those with the highest volume of colonoscopy(P=0.049).Forty percent of participants were unsure of CTC's impact on future colonoscopy volume while 21% and 18% projected a decreased and increased volume,respectively.The estimated impact of CTC volume varied significantly by age(P=0.002).Respondents > 60 years felt that CTC would increase colonoscopy,whereas those < 40 years thought CTC would ultimately decrease colonoscopy.CONCLUSION:Practicing endoscopists are not enthusiastic about the incorporation of CTC into their daily practice and are unsure of its future impact on their practice.展开更多
基金Supported by An American College of Gastroenterology Junior Faculty Development Award to Linda C Cummings
文摘Colorectal cancer(CRC) is the 2^(nd) most common cancer in women and 3^(rd) most common cancer in men worldwide. Most CRCs develop from adenomatous polyps arising from glandular epithelium. Tumor growth is initiated by mutation of the tumor suppressor gene APC and involves other genetic mutations in a stepwise process over years. Both hereditary and environmental factors contribute to the development of CRC. Screening has been proven to reduce the incidence of CRC. Screening has also contributed to the decrease in CRC mortality in the United States. However,CRC incidence and/or mortality remain on the rise in some parts of the world(Eastern Europe,Asia,and South America),likely due to factors including westernized diet,lifestyle,and lack of healthcare infrastructure. Multiple screening options are available,ranging from direct radiologic or endoscopic visualization tests that primarily detect premalignant or malignant lesions such as flexible sigmoidoscopy,optical colonoscopy,colon capsule endoscopy,computed tomographic colonography,and double contrast barium enema- to stool based tests which primarily detect cancers,including fecal DNA,fecal immunochemical test,and fecal occult blood test. The availability of some of these tests is limited to areas with high economic resources. This article will discuss CRC epidemiology,pathogenesis,risk factors,and screening modalities with a particular focus on new technologies.
基金Supported by Grant from Guangdong Provincial Science and Technology Program,No. 2011B031800182
文摘AIM:To evaluate the efficacy of reduced cathartic bowel preparation with 2 L polyethylene glycol(PEG)-4000 electrolyte solution and 10 mg bisacodyl enteric-coated tablets for computed tomographic colonography(CTC).METHODS:Sixty subjects who gave informed consent were randomly assigned to study group A,study group B or the control group.On the day prior to CTC,subjects in study group A were given 20 mL 40% wt/vol barium sulfate suspension before 3 mealtimes,60 mL 60% diatrizoate meglumine diluted in 250 mL water after supper,and 10 mg bisacodyl enteric-coated tablets 1 h before oral administration of 2 L PEG-4000 electrolyte solution.Subjects in study group B were treated identically to those in study group A,with the exception of bisacodyl which was given 1 h after oral PEG-4000.Subjects in the control group were managed using the same strategy as the subjects in study group A,but without administration of bisacodyl.Residual stool and fluid scores,the attenuation value of residual fluid,and discomfort during bowel preparation in the three groups were analyzed statistically.RESULTS:The mean scores for residual stool and fluid in study group A were lower than those in study group B,but the differences were not statistically significant.Subjects in study group A showed greater stool and fluid cleansing ability than the subjects in study group B.The mean scores for residual stool and fluid in study groups A and B were lower than those in the control group,and were significantly different.There was no significant difference in the mean attenuation value of residual fluid between study group A,study group B and the control group.The total discomfort index during bowel preparation was 46,45 and 45 in the three groups,respectively,with no significant difference.CONCLUSION:Administration of 10 mg bisacodyl enteric-coated tablets prior to or after oral administration of 2 L PEG-4000 electrolyte solution enhances stool and fluid cleansing ability,and has no impact on the attenuation value of residual fluid or the discomfort
文摘Computed tomographic colonography (CTC) is a promising emerging technology for imaging of the colon. This concise review discusses the currently available data on CTC technique,test characteristics,acceptance,safety,cost-effectiveness,follow-up strategy,and extracolonic findings. In summary,CTC technique is still evolving,and further research is needed to clarify the role of automated colonic insufflation,smooth-muscle relaxants,intravenous and oral contrast,soft-ware rendering,and patient positioning. Currently,full bowel preparation is still required to achieve optimal results. The sensitivity for detecting large polyps (> 1 cm) can be as high as 85%,with specificity of up to 97%. These test characteristics are almost comparable to those of conventional colonoscopy. Patient acceptance of CTC is generally higher than that for colonoscopy,especially in patients who have never undergone either procedure. CTC is generally safe,although uncommon instances of colonic perforation have been documented. In terms of cost-effectiveness,most decision analyses have concluded that CTC would only be cost-effective if it were considerably cheaper than conventional colonoscopy. The proper follow-up strategy for small polyps or incidental extracolonic findings discovered during CTC is still under debate. At present,the exact clinical role of virtual colonoscopy still awaits determination. Even though widespread CTC screening is not available today,in the future there may eventually be a role for this technology. Technological advances in this area will undoubtedly continue,with multi-detector row CT scanners allowing thinner collimation and higher reso-lution images. Stool-tagging techniques are likely to evolve and may eventually allow for low-preparation CTC. Perceptual and fatigue-related reading errors can potentially be minimized with the help of computer-aided detection software. Further research will define the exact role of this promising technology in our diagnostic armamentarium.
文摘AIM:To investigate the perceived impact of computed tomographic colonography(CTC) on endoscopists' current and future practice.METHODS:A 21-question survey was mailed to 1570 randomly chosen American Society for Gastrointestinal Endoscopy(ASGE) members.Participants reported socio-demographics,colonoscopy volume,percentage of colonoscopies performed for screening,and likelihood of integration of CTC into their practice.RESULTS:A total of 367 ASGE members(23%) returned the questionnaire.Respondents were predominantly male(> 90%) and white(83%) with an average age of 49 years.Most respondents(58%) had no plans to incorporate CTC into daily practice and only 7% had already incorporated CTC into daily practice.Private practice respondents were the least likely to incorporate this modality into their daily practice(P=0.047).Forty-three percent of participants were willing to take courses on CTC reading,particularly those with the highest volume of colonoscopy(P=0.049).Forty percent of participants were unsure of CTC's impact on future colonoscopy volume while 21% and 18% projected a decreased and increased volume,respectively.The estimated impact of CTC volume varied significantly by age(P=0.002).Respondents > 60 years felt that CTC would increase colonoscopy,whereas those < 40 years thought CTC would ultimately decrease colonoscopy.CONCLUSION:Practicing endoscopists are not enthusiastic about the incorporation of CTC into their daily practice and are unsure of its future impact on their practice.
