| [ Summary ] |
It is widely known that sessile or pedunculated adenoma progress to early and advanced cancer of the colon. For a long time, clinicians have focused on the advantages of polypectomy in the treatment of colorectal neoplasm. However, colorectal cancer has not decreased statistically. On the other hand, the presence of depressed lesions of early colorectal cancer has been reported. Now there are two theories in development of colorectal neoplasm. The "adenoma-carcinoma sequence" theory and "de novo" theory. Thus, we are greatly concerned with the "de novo" theory and depressed lesions of early colorectal cancer. However, there are few case of depressed lesions statistically. This is probably because many clinicians either overlooked them, or have little knowledge about their characteristic findings on colonoscopic examination. This paper deals with five viewpoints on colonoscopic examination for depressed lesions of colorectal neoplasm, pretreatment (preparation), the insertion technique, the scope control technique, a finding characteristic of depressed lesions, and magnifying endoscopic findings. All colonoscopists must be conscious of depressed lesions seen on endoscopic examination. |