대한대장항문학회

To assess the clinico-pathological characteristics of patients with multiple primary colorectal cancer, 458 patients who underwent curative surgery and being followed-up at our institution between Jan. 1987 and Dec. 1993 were evaluated in this study.<br>The median follow-up period was 42 months. Synchronous cancer was defined as distinct lesions separated by a distance of greater than 4cm with the invasion of the tumor below the muscularis mucosa at the time of diagnosis or within 6 months after<br>initial treatment, and metachronous cancer was defined as the development of colon cancers more than 6 months after the initial treatment without evidence of the recurrence or metastases from primary tumor. There were 29 cases of multiple primary<br>colorectal cancer(6.3%). Eighteen cases(3.9%) of them were synchronous, 11 cases(2.4%) were metachronous cancers. Seven cases(1.5%) were related to 5 hereditary non-polyposis colorectal cancer(HNPCC) families. During the follow-up period, 11<br>patients(2.4%) developed cancers in other organs. Adenomatous polyps were identified 14 cases of 29 patients with multiple primary colorectal cancers(48.3%), compared to 43 cases(10%) in 429 patients with solitary colorectal cancer(p＜0.01). After<br>initial curative surgery, there were 8 recurrences in 29 patients with multiple primary colorectal cancers(23.6%), compared to 100 recurrences in 429 patients with solitary primary colorectal cancer(23.3%)(p＞0.05). In aspect of family history, there<br>was close-relationship with this regarding in the group of multiple primary colorectal cancers. However, authors were unable to make analysis this regarding in the group of solitary primaries because of lack of the information. Conclusively, authors<br>guess the frequent association of the adenomatous polyps in multiple primary colorectal cancers as the evidence of the adenoma-carcinoma sequence. In addition, authors emphasized the importance of the total colonoscopic examinations in pre-and<br>post-operation in order to make diagnosis of the multiple primary colorectal cancers and paying attention as to the family history of colorectal cancer patients because we have good therapeutic results after operation of early stage in synchronous<br>cancers and co-existent adenomatous polyps.<br>