| Theme |
Prevalence of the IIc type colorectal neoplasm |
| Title |
Estimated incidence of colorectal de novo cancer among people in average risk category |
| Author |
Hideyo Goto |
Hattori GI Endoscopy and Gastroenterology Clinic |
| Author |
Yasushi Oda |
Hattori GI Endoscopy and Gastroenterology Clinic |
| Author |
Yoshitaka Murakami |
Epidemiology and International Health Research Section Environmental Health Sciences Division National Institute for Environmental Studies |
| Author |
Sayoko Goto |
Hattori GI Endoscopy and Gastroenterology Clinic |
| Author |
Tomofumi Tanaka |
Hattori GI Endoscopy and Gastroenterology Clinic |
| Author |
Kiwamu Hasuda |
Hattori GI Endoscopy and Gastroenterology Clinic |
| Author |
Kazuya Nakahara |
Hattori GI Endoscopy and Gastroenterology Clinic |
| Author |
Masahiro Hattori |
Hattori GI Endoscopy and Gastroenterology Clinic |
| [ Summary ] |
Although it is well known that colorectal cancer can originate from a pre-existing adenoma or a de novo condition, the relative importance of these two theories is still controversial and rarely quantified. The aim of this study is to estimate the proportion of colorectal de novo cancer among people in the average risk category.
The subjects were 15,327 persons over 40 years of age who met the conditions of having no history of advanced neoplasia and not having been previously consulted. We diagnosed 212 colorectal cancers (96 early and 116 advanced cancers) in endoscopically or surgically resected specimens. There were 111 early stage cancers, of which origins could be diagnosed and were used for this study. The percentage of de novo cancer in the patient lifetime was 30.6%, and the age group with the highest incidence was 41.7% for people in their 60s', followed by 32% for people in their 50s'. The lifetime risk for colorectal cancer, based on the data in this study, was 7.67% in men and 5.42% in women, compared to that based on the SEER data in the United States which was 6.31% in men and 5.94% in women. The incidence rate of colorectal cancer for people aged 40-60 in this study correspond to that for people aged 50-70 years in the SEER data. From these results, we suggest total colonoscopy every 3 to 5 years, which is acceptable for medical costs in Japan, and can detect most colorectal cancer in the early stages. |