Clinicopathologic Characteristics of Colorectal Mucinous Carcinoma

Purpose: The aim of this study was to assess the clinicopathological characteristics and prognosis of colorectal mucinous carcinomas. Methods: 1,809 patients who underwent curative resection, between January 1989 and December 1999, for colorectal carcinomas, were enrolled in this study. Of these, 128 patients had more than 50% mucin secreting acini that could be classified as the mucinous type. These mucinous carcinoma patients were compared with 1,681 non-mucinous carcinoma patients, in order to evaluate differences in their clinicopathological characteristics, recurrence pattern and prognosis. Results: The incidence of mucinous carcinomas was 7.1%. The mean age of the mucinous carcinoma patients was younger than the non-mucinous carcinoma patients (P=0.001). The mucinous carcinomas occurred in the right colon more frequently than non-mucinous carcinoma, and the size of the tumor was larger (P＜0.001). There were no significant differences in the loco-regional and systemic recurrence rates, but the systemic recurrence pattern of the mucinous carcinomas was different from those of the non-mucinous carcinomas. With a mucinous carcinoma, the most common site for systemic recurrence was the peritoneal metastasis, whereas in a non-mucinous carcinoma, was the liver. There was no significant difference in the 5-year survival rate between the two groups. Conclusion: In a mucinous carcinoma, the most common pattern of treatment failure was a peritoneal recurrence. The hepatic recurrence rate of the mucinous carcinomas was less than that of the non-mucinous carcinoma. Therefore, more aggressive diagnostic and therapeutic approaches, under the consideration of peritoneal recurrence in mucinous carcinomas, will be required.ope