Mucinous carcinomas of the colon and rectum. An analysis of 62 stage B and C lesions.

The significance of a large extracellular mucinous component in colorectal adenocarcinomas continues to be controversial. We studied 62 stage B and C mucinous carcinomas defined by 60% or greater mucinous component. Sixty of these patients had matched nonmucinous adenocarcinoma controls. Patients with mucinous carcinomas with a residual adenoma had a significantly greater survival than those who did not. Overall, no difference was noted in 5-year survival between patients with mucinous carcinoma and nonmucinous adenocarcinoma (64% each). However, when the stages were considered separately, patients with stage B mucinous carcinoma fared significantly worse and had more local sites of treatment failure. We speculate that patients with stage B mucinous carcinoma may have a worse prognosis owing to the extra-cellular mucin, which may make a complete surgical extirpation more difficult.