AIM: To clarify the usefulness of the self-expanding metallic stents (SEMS) in the management of acute proximal colon obstruction due to colon carcinoma before curative surgery.METHODS: Eighty-one colon (proximal to s...AIM: To clarify the usefulness of the self-expanding metallic stents (SEMS) in the management of acute proximal colon obstruction due to colon carcinoma before curative surgery.METHODS: Eighty-one colon (proximal to spleen flex) carcinoma patients (47 males and 34 females,aged 18-94 years,mean = 66.2 years) treated between September 2004 and June 2010 for acute colon obstruction were enrolled to this study,and their clinical and radiological features were reviewed.After a cleaning enema was administered,urgent colonoscopy was performed.Subsequently,endoscopic decompression using SEMS placement was attempted.RESULTS: Endoscopic decompression using SEMS placement was technically successful in 78 (96.3%) of 81 patients.Three patients’ symptoms could not be relieved after SEMS placement and emergent operation was performed 1 d later.The site of obstruction was transverse colon in 18 patients,the hepatic flex in 42,and the ascending colon in 21.Following adequate cleansing of the colon,patients’ abdominal girth was decreased from 88 ± 3 cm before drainage to 72 ± 6 cm 7 d later,and one-stage surgery after 8 ± 1 d (range,7-10 d) was performed.No anastomotic leakage or postoperative stenosis occurred after operation.CONCLUSION: SEMS placement is effective and safe in the management of acute proximal colon obstruction due to colon carcinoma,and is considered as a bridged method before curative surgery.展开更多
AIM: To review the risk of proximal colon cancer in patients undergoing colonoscopy.METHODS: We estimated the risk of advanced proximal adenomas and cancers in 6 196 consecutive patients that underwent colonoscopy (me...AIM: To review the risk of proximal colon cancer in patients undergoing colonoscopy.METHODS: We estimated the risk of advanced proximal adenomas and cancers in 6 196 consecutive patients that underwent colonoscopy (mean age 60 years, 65% males,without prior history of colorectal examination). Neoplasms were classified as diminutive adenoma (5 mm or less),small adenoma (6-9 mm), advanced adenoma (10 mm or more, with villous component or high-grade dysplasia)and cancer (invasive adenocarcinoma). The sites of neoplasms were defined as rectosigmoid (rectum and sigmoid colon) and proximal colon (from cecum to descending colon).RESULTS: The trend of the prevalence of advanced proximal adenoma was to increase with severe rectosigmoid findings, while the prevalence of proximal colon cancer did not increase with severe rectosigmoid findings. Among the 157 patients with proximal colon cancer, 74% had no neoplasm in the rectosigmoid colon. Multivariate logisticregression analysis revealed that age was the main predictor of proximal colon cancer and existence of rectosigmoid adenoma was not a predictor of proximal colon cancer.CONCLUSION: Sigmoidoscopy is inadequate for colorectal cancer screening, especially in older populations.展开更多
Colonoscopy and polypectomy remain the gold standard investigation for the detection and prevention of colorectal cancer.Halting the progression of colonic adenoma through adequate detection of pre-cancerous lesions i...Colonoscopy and polypectomy remain the gold standard investigation for the detection and prevention of colorectal cancer.Halting the progression of colonic adenoma through adequate detection of pre-cancerous lesions interrupts the progression to carcinoma.The adenoma detection rate is a key performance indicator.Increasing adenoma detection rates are associated with reducing rates of interval colorectal cancer.Endoscopists with high baseline adenoma detection rate have a meticulous technique during colonoscopy withdrawal that improves their adenoma detection.This minireview article summarizes the evidence on the following simple operator techniques and their effects on the adenoma detection rate;minimum withdrawal times,dynamic patient position change and proximal colon retroflexion.展开更多
Understanding of the mechanism of colorectal carcinogenesis has been gaining momentum for some years on account of its high incidence and impact on the lives of individuals affected. Different genetic abnormalities ha...Understanding of the mechanism of colorectal carcinogenesis has been gaining momentum for some years on account of its high incidence and impact on the lives of individuals affected. Different genetic abnormalities have been found in colorectal cancers from different sites. For example, proximal colon cancer is usually related to the nucleotide instability pathway, as microsatellite instability (MSI). However, distal colon cancer is usually associated with specific chromosomal instability (CIN). The development of cancer at the rectum, though similar to that at the colon, displays its own unique features. These differences might be partially attributed to different embryological development and physiological circumstances. Environmental factors such as diet and alcohol intake also differ in their role in the development of tumors in the three segments, proximal colon, distal colon, and rectum. "Proximal shift" of colon cancer has been known for some time, and survival rates of colorectal cancer are higher when rectal cancers are excluded, both of which emphasize the three different segments of coloreetal cancer and their different properties. Meanwhile, colonic and rectal cancers are distinctive therapeutic entities. The concept of three entities of coloreetal cancer may be important in designing clinical trails or therapeutic strategies. However, the dispute about the inconsistency of data coneerning the site-specific mechanism of eolorectal carcinoma does exist, and more evidence about molecular events of carcinogenesis and targeted therapy needs to be collected to definitely confirm the conception.展开更多
Objective:To investigate the incidence and trends in colorectal cancer(CRC)among Asian American populations in the United States.Methods:CRC incidence data from 1994 through 2013 were obtained from 13 Surveillance,Epi...Objective:To investigate the incidence and trends in colorectal cancer(CRC)among Asian American populations in the United States.Methods:CRC incidence data from 1994 through 2013 were obtained from 13 Surveillance,Epidemiology,and End Results registries.SEER*Stat and IBM SPSS Statistics were used.Results:The age-adjusted incidence of CRC among Asian Americans decreased from 45.6 per 100,000 in 1994 to 33.0 per 100,000 in 2013,with the annual percent change being−1.8%(P<0.05).The incidences were higher for men,the elderly(aged 60 years or older),and several geographic areas.For those younger than 70 years,the rectal site was more affected compared with those aged 70 years or older,in whom the proximal site were more affected.Most patients presented with localized and regional stages.Men,80 years or older,in situ stage,and some geo-graphic areas such as Connecticut and California experienced significant incidence decreases in the 20-year observation period.Conclusion:Although CRC incidence has declined among Asian American populations in the United States in the past 2 decades,there are persistent differences by age and geographic areas.Further research is needed to guide the design and implementation of tailored strategies to reduce CRC outcome differences across Asian American populations.展开更多
基金Supported by Shanghai Science and Technology Committee,No.09411967100Shanghai Municipal Health Bureau,No.2007Y38
文摘AIM: To clarify the usefulness of the self-expanding metallic stents (SEMS) in the management of acute proximal colon obstruction due to colon carcinoma before curative surgery.METHODS: Eighty-one colon (proximal to spleen flex) carcinoma patients (47 males and 34 females,aged 18-94 years,mean = 66.2 years) treated between September 2004 and June 2010 for acute colon obstruction were enrolled to this study,and their clinical and radiological features were reviewed.After a cleaning enema was administered,urgent colonoscopy was performed.Subsequently,endoscopic decompression using SEMS placement was attempted.RESULTS: Endoscopic decompression using SEMS placement was technically successful in 78 (96.3%) of 81 patients.Three patients’ symptoms could not be relieved after SEMS placement and emergent operation was performed 1 d later.The site of obstruction was transverse colon in 18 patients,the hepatic flex in 42,and the ascending colon in 21.Following adequate cleansing of the colon,patients’ abdominal girth was decreased from 88 ± 3 cm before drainage to 72 ± 6 cm 7 d later,and one-stage surgery after 8 ± 1 d (range,7-10 d) was performed.No anastomotic leakage or postoperative stenosis occurred after operation.CONCLUSION: SEMS placement is effective and safe in the management of acute proximal colon obstruction due to colon carcinoma,and is considered as a bridged method before curative surgery.
文摘AIM: To review the risk of proximal colon cancer in patients undergoing colonoscopy.METHODS: We estimated the risk of advanced proximal adenomas and cancers in 6 196 consecutive patients that underwent colonoscopy (mean age 60 years, 65% males,without prior history of colorectal examination). Neoplasms were classified as diminutive adenoma (5 mm or less),small adenoma (6-9 mm), advanced adenoma (10 mm or more, with villous component or high-grade dysplasia)and cancer (invasive adenocarcinoma). The sites of neoplasms were defined as rectosigmoid (rectum and sigmoid colon) and proximal colon (from cecum to descending colon).RESULTS: The trend of the prevalence of advanced proximal adenoma was to increase with severe rectosigmoid findings, while the prevalence of proximal colon cancer did not increase with severe rectosigmoid findings. Among the 157 patients with proximal colon cancer, 74% had no neoplasm in the rectosigmoid colon. Multivariate logisticregression analysis revealed that age was the main predictor of proximal colon cancer and existence of rectosigmoid adenoma was not a predictor of proximal colon cancer.CONCLUSION: Sigmoidoscopy is inadequate for colorectal cancer screening, especially in older populations.
文摘Colonoscopy and polypectomy remain the gold standard investigation for the detection and prevention of colorectal cancer.Halting the progression of colonic adenoma through adequate detection of pre-cancerous lesions interrupts the progression to carcinoma.The adenoma detection rate is a key performance indicator.Increasing adenoma detection rates are associated with reducing rates of interval colorectal cancer.Endoscopists with high baseline adenoma detection rate have a meticulous technique during colonoscopy withdrawal that improves their adenoma detection.This minireview article summarizes the evidence on the following simple operator techniques and their effects on the adenoma detection rate;minimum withdrawal times,dynamic patient position change and proximal colon retroflexion.
基金supported by the Program of Science and Technology in the National "Eleventh 5-year Plan" of China (No. 2006BAI0214)the Foundation of Science and Technology of Hangzhou City, China (No. 20061123B02)
文摘Understanding of the mechanism of colorectal carcinogenesis has been gaining momentum for some years on account of its high incidence and impact on the lives of individuals affected. Different genetic abnormalities have been found in colorectal cancers from different sites. For example, proximal colon cancer is usually related to the nucleotide instability pathway, as microsatellite instability (MSI). However, distal colon cancer is usually associated with specific chromosomal instability (CIN). The development of cancer at the rectum, though similar to that at the colon, displays its own unique features. These differences might be partially attributed to different embryological development and physiological circumstances. Environmental factors such as diet and alcohol intake also differ in their role in the development of tumors in the three segments, proximal colon, distal colon, and rectum. "Proximal shift" of colon cancer has been known for some time, and survival rates of colorectal cancer are higher when rectal cancers are excluded, both of which emphasize the three different segments of coloreetal cancer and their different properties. Meanwhile, colonic and rectal cancers are distinctive therapeutic entities. The concept of three entities of coloreetal cancer may be important in designing clinical trails or therapeutic strategies. However, the dispute about the inconsistency of data coneerning the site-specific mechanism of eolorectal carcinoma does exist, and more evidence about molecular events of carcinogenesis and targeted therapy needs to be collected to definitely confirm the conception.
文摘Objective:To investigate the incidence and trends in colorectal cancer(CRC)among Asian American populations in the United States.Methods:CRC incidence data from 1994 through 2013 were obtained from 13 Surveillance,Epidemiology,and End Results registries.SEER*Stat and IBM SPSS Statistics were used.Results:The age-adjusted incidence of CRC among Asian Americans decreased from 45.6 per 100,000 in 1994 to 33.0 per 100,000 in 2013,with the annual percent change being−1.8%(P<0.05).The incidences were higher for men,the elderly(aged 60 years or older),and several geographic areas.For those younger than 70 years,the rectal site was more affected compared with those aged 70 years or older,in whom the proximal site were more affected.Most patients presented with localized and regional stages.Men,80 years or older,in situ stage,and some geo-graphic areas such as Connecticut and California experienced significant incidence decreases in the 20-year observation period.Conclusion:Although CRC incidence has declined among Asian American populations in the United States in the past 2 decades,there are persistent differences by age and geographic areas.Further research is needed to guide the design and implementation of tailored strategies to reduce CRC outcome differences across Asian American populations.