Mucinous component in colorectal carcinoma--prognostic significance: a study in a south Indian population.

One hundred eighteen specimens of colorectal carcinoma have been studied with a view to assess the clinicopathological significance of the mucinous component in these neoplasms. When 50% or more of high-power fields examined consisted of "mucinous" tumour tissue, the term mucinous carcinoma was applied. Such mucinous carcinomas (MCa) constituted 19% of the total neoplasms studied. Predilection for the younger age group, a higher incidence in the proximal colon as against the rectosigmoid, and a lower distribution in the rectosigmoid as against nonmucinous carcinomas in that region were some of the features that characterised MCa. Clinical and histological features suggestive of aggressive behaviour and poor prognosis were more frequently observed in MCa. These features correlated with the percentage of mucinous component independently of the histological grade. It is concluded that colorectal mucinous carcinomas form a distinct group of neoplasms with certain clinical and pathological characteristics. These neoplasms tend to follow an aggressive clinical course, which is directly influenced by the mucinous component.