Abstract
We studied 1103 cases with a positive immunochemical fecal occult blood test undergoing total colonoscopy at our hospital (Itabashi Chuo Hospital) during the period from January 2011 through December 2012. At first, we divided our subjects into two groups: the group less than 65 years of age and the group 65 years of age or older and compared them regarding the following aspects: the number and size of the polyps, detection rate and location of colorectal cancer and early cancer ratio, and location of colorectal adenoma. We also made the same comparisons between genders. With regard to the location of colorectal cancer and adenoma, we compared between the right (including the cecum, ascending and transverse colon) and left colon (including descending and sigmoid colon and rectum). As a result, we found that there were significantly larger and more multiple polyps were in the elderly. We also found the detection rates both of colorectal cancer and of adenoma in the right colon were significantly higher in the elderly. There was a significant difference in the early cancer ratio between the age groups, with the advanced cancer being more prevalent in the elderly. With regard to gender, we found there were more multiple polyps in males. There were no significant differences concerning the other aspects between genders. With the findings of a higher prevalence both of cancer and of adenoma in the right colon in the elderly, it is extremely important to complete TCS in the elderly with a positive immunochemical fecal occult blood test, to reduce the morbidity and mortality of colorectal cancer.
