Colorectal carcinoma associated with schistosomiasis: a possible causal relationship.

The association between schistosomiasis and colorectal malignancy has long been suggested in the literature, but it is not uniformly accepted. In the Far East, considerable evidence supports an etiological link between Schistosoma japonicum and colorectal cancer. However, the available data regarding the role of Schistosoma mansoni in colorectal carcinogenesis are conflicting and most often do not show causality. We report on a patient with sigmoid colonic cancer coexisting with schistosomiasis, and we provide a comprehensive review of the literature regarding the epidemiology and pathobiology of this association.