Prognosis and Recurrent Patterns of Sporadic Primary Colon Cancers According to Location

ABSTRACT

PURPOSE: We aimed to compare the prognosis and the recurrence patterns of sporadic primary colon cancers according to the location of the cancer. METHODS: One thousand four-hundred eighty-three (1,483) stage II, III colon cancer patients who had undergone a consecutive curative resection between January 1989 and December 2003 were analyzed. Hereditary, synchronous, metachronous, and recurrent colon cancers were excluded. The right colon was defined as being from the cecum to the transverse colon, and the left colon was defined as being from the splenic flexure colon to the rectosigmoid colon. The median follow-up time was 63 (3-228) mo. RESULTS: Poorly differentiated and mucinous cell type tumors were more frequent in the right colon. T3 tumors were more frequent in the right colon. Lymph-node-positive tumors were more frequent in the left colon. The recurrence rate was higher in the left colon, but the patterns of recurrence were not different according to the tumor's location. By univariate analysis, age, preoperative serum CEA level, T-stage, N-stage, lymphovascular invasion, postoperative chemotherapy, and tumor location were significant prognostic factors associated with recurrence. By multivariate analysis, sex, preoperative serum CEA level, T-stage, N-stage, postoperative chemotherapy, and tumor location were significant prognostic factors associated with recurrence. The 5-yr disease-free survival rates were 84.0% for right colon cancer and 77.1% for left colon cancer (P=0.005). The recurrence rates for cancers in the sigmoid colon and the rectosigmoid colon were higher than those for cancers in the cecum and the ascending colon. CONCLUSION: The tumor's location was an independent prognostic factor for recurrence, but the pattern of recurrence did not vary with the tumor's location.