Imaging studies are a major component in the evaluation of patients for the screening,staging and surveillance of colorectal cancer.This review presents commonly encountered findings in the diagnosis and staging of pa...Imaging studies are a major component in the evaluation of patients for the screening,staging and surveillance of colorectal cancer.This review presents commonly encountered findings in the diagnosis and staging of patients with colorectal cancer using computed tomography(CT)colonography,magnetic resonance imaging(MRI),and positron emission tomography(PET)/CT colonography.CT colonography provides important information for the preoperative assessment of T staging.Wall deformities are associated with muscular or subserosal invasion.Lymph node metastases from colorectal cancer often present with calcifications.CT is superior to detect calcified metastases.Three-dimensional CT to image the vascular anatomy facilitates laparoscopic surgery.T staging of rectal cancer by MRI is an established modality because MRI can diagnose rectal wall laminar structure.N staging in patients with colorectal cancer is still challenging using any imaging modality.MRI is more accurate than CT for the evaluation of liver metastases.PET/CT colonography isvaluable in the evaluation of extra-colonic and hepatic disease.PET/CT colonography is useful for obstructing colorectal cancers that cannot be traversed colonoscopically.PET/CT colonography is able to localize synchronous colon cancers proximal to the obstruction precisely.However,there is no definite evidence to support the routine clinical use of PET/CT colonography.展开更多
BACKGROUND Computed tomography colonography(CTC)may be superior to colonoscopy and barium enema for detecting diverticula.However,few studies have used CTC to diagnose diverticula.AIM To evaluate the current prevalenc...BACKGROUND Computed tomography colonography(CTC)may be superior to colonoscopy and barium enema for detecting diverticula.However,few studies have used CTC to diagnose diverticula.AIM To evaluate the current prevalence and distribution of colonic diverticula in Japan using CTC.METHODS This study was conducted as part of the Japanese National Computed Tomographic Colonography Trial,which included 1181 participants from 14 hospitals in Japan.We analyzed the prevalence and distribution of colonic diverticula and their relationships with age and sex.The relationship between the diverticula and the length of the large intestine was also analyzed.RESULTS Diverticulosis was present in 48.1%of the participants.The prevalence of diverticulosis was higher in the older participants(P<0.001 for trend).The diverticula seen in younger participants were predominantly located in the right-sided colon.Older participants had a higher frequency of bilateral type(located in the rightand left-sided colon)diverticulosis(P<0.001 for trend).The length of the large intestine with multiple diverticula in the sigmoid colon was significantly shorter in those without diverticula(P<0.001).CONCLUSION The prevalence of colonic diverticulosis in Japan is higher than that previously reported.The prevalence was higher,and the distribution tended to be bilateral in older participants.展开更多
According to the guidelines by the Japanese government, optical colonoscopy is the most strongly recommended diagnostic test after screening with the immunochemical fecal occult blood test (iFOBT), followed by double-...According to the guidelines by the Japanese government, optical colonoscopy is the most strongly recommended diagnostic test after screening with the immunochemical fecal occult blood test (iFOBT), followed by double-contrast barium enema (BE) or sigmoidoscopy. Our study was to assess patterns and trends of colorectal cancer (CRC) diagnostic testing within 2 years after iFOBT. We analyzed both iFOBT results and claims data provided by employee health insurance societies in Japan from 2005 to 2010. 25,596 enrollees underwent iFOBT screening. The positive rate was 5.1%. 32.3% of those positive underwent diagnostic tests and 1.0% (12 patients) were confirmed as having cancer. The most common test was optical colonoscopy (77.2% of total tests), followed by BE (16.2%). From 2006 to 2009, the rate of optical colonoscopy for females increased from 55% to 82% and that of BE declined from 36% to 12%, while no significant changes were seen for males. Only one-third of those who tested positive underwent diagnostic test in the 2 years following screening iFOBT. As official guidelines for diagnostic testing of CRC recommend, optical colonoscopy is now the most commonly used diagnostic test after positive iFOBT result for enrollees in employee health insurance societies in Japan.展开更多
文摘Imaging studies are a major component in the evaluation of patients for the screening,staging and surveillance of colorectal cancer.This review presents commonly encountered findings in the diagnosis and staging of patients with colorectal cancer using computed tomography(CT)colonography,magnetic resonance imaging(MRI),and positron emission tomography(PET)/CT colonography.CT colonography provides important information for the preoperative assessment of T staging.Wall deformities are associated with muscular or subserosal invasion.Lymph node metastases from colorectal cancer often present with calcifications.CT is superior to detect calcified metastases.Three-dimensional CT to image the vascular anatomy facilitates laparoscopic surgery.T staging of rectal cancer by MRI is an established modality because MRI can diagnose rectal wall laminar structure.N staging in patients with colorectal cancer is still challenging using any imaging modality.MRI is more accurate than CT for the evaluation of liver metastases.PET/CT colonography isvaluable in the evaluation of extra-colonic and hepatic disease.PET/CT colonography is useful for obstructing colorectal cancers that cannot be traversed colonoscopically.PET/CT colonography is able to localize synchronous colon cancers proximal to the obstruction precisely.However,there is no definite evidence to support the routine clinical use of PET/CT colonography.
文摘BACKGROUND Computed tomography colonography(CTC)may be superior to colonoscopy and barium enema for detecting diverticula.However,few studies have used CTC to diagnose diverticula.AIM To evaluate the current prevalence and distribution of colonic diverticula in Japan using CTC.METHODS This study was conducted as part of the Japanese National Computed Tomographic Colonography Trial,which included 1181 participants from 14 hospitals in Japan.We analyzed the prevalence and distribution of colonic diverticula and their relationships with age and sex.The relationship between the diverticula and the length of the large intestine was also analyzed.RESULTS Diverticulosis was present in 48.1%of the participants.The prevalence of diverticulosis was higher in the older participants(P<0.001 for trend).The diverticula seen in younger participants were predominantly located in the right-sided colon.Older participants had a higher frequency of bilateral type(located in the rightand left-sided colon)diverticulosis(P<0.001 for trend).The length of the large intestine with multiple diverticula in the sigmoid colon was significantly shorter in those without diverticula(P<0.001).CONCLUSION The prevalence of colonic diverticulosis in Japan is higher than that previously reported.The prevalence was higher,and the distribution tended to be bilateral in older participants.
文摘According to the guidelines by the Japanese government, optical colonoscopy is the most strongly recommended diagnostic test after screening with the immunochemical fecal occult blood test (iFOBT), followed by double-contrast barium enema (BE) or sigmoidoscopy. Our study was to assess patterns and trends of colorectal cancer (CRC) diagnostic testing within 2 years after iFOBT. We analyzed both iFOBT results and claims data provided by employee health insurance societies in Japan from 2005 to 2010. 25,596 enrollees underwent iFOBT screening. The positive rate was 5.1%. 32.3% of those positive underwent diagnostic tests and 1.0% (12 patients) were confirmed as having cancer. The most common test was optical colonoscopy (77.2% of total tests), followed by BE (16.2%). From 2006 to 2009, the rate of optical colonoscopy for females increased from 55% to 82% and that of BE declined from 36% to 12%, while no significant changes were seen for males. Only one-third of those who tested positive underwent diagnostic test in the 2 years following screening iFOBT. As official guidelines for diagnostic testing of CRC recommend, optical colonoscopy is now the most commonly used diagnostic test after positive iFOBT result for enrollees in employee health insurance societies in Japan.
