| Theme |
Clinical Management of Colorectal Polyps |
| Title |
Surveillance after Endoscopic Treatment for Colorectal Tumors Considering Concept of Semi-clean Colon |
| Author |
Shiro Oka |
Department of Endoscopy, Hiroshima University Hospital |
| Author |
Shinji Tanaka |
Department of Endoscopy, Hiroshima University Hospital |
| Author |
Iwao Kaneko |
Department of Endoscopy, Hiroshima University Hospital |
| Author |
Hiroyuki Ueda |
Department of Medicine and Molecular Science, Graduate School of Biomedical Sciences, Hiroshima University |
| Author |
Masaharu Yoshihara |
Health Service Center, Hiroshima University |
| Author |
Kazuaki Chayama |
Department of Medicine and Molecular Science, Graduate School of Biomedical Sciences, Hiroshima University |
| [ Summary ] |
An appropriate surveillance method after endoscopic resection for colorectal tumors was explored based on the cumulative incidence rate of metachronous multiple lesions (adenomas and carcinomas) and the clinical characteristics of invasive carcinomas found during follow-up examinations on patients who had follow-up examinations after being diagnosed as having a semi-clean colon (cases without colorectal tumors over 5 mm in diameter). The cumulative incidence rate of metachronous multiple lesions was 60.0% for adenomas and 7.7% for carcinomas, showing a significantly higher rate for adenomas, compared to carcinomas. The average follow-up examination period, until the metachronous multiple lesions were found, was 26.3+-7.1 months for adenomas and 28.0+-5.3 months for carcinomas. Furthermore, on the basis of the primary lesions seen in these cases, the cumulative incidence rate for metachronous multiple carcinomas was significantly higher for cases of multiple carcinoma, compared to the cases of single carcinoma and the cases of carcinoma compared to cases of adenoma. Some of the clinical characteristics of invasive carcinomas found during follow-up examinations were that they were found more often in cases having had previous surgery for colorectal carcinoma. This was seen because they exist in blind spots, such as behind folds and in the flexures, and because they were surface lesions. Therefore, the surveillance method after achieving a semi-clean colon employs total colonoscopy, which should be conducted one year later for the prevention of overlooked cases and also conducted once every three years after that examination. After those examinations, it may be prudent to change the time of examination intervals in accordance with the risk of primary lesions in each case. |