[Light and electron microscopic studies of relationship between colon carcinoma and schistosomiasis]

The light and electron microscopic observations were carried out in 50 cases of colon specimens. No remarkable morphologic differences were found between the epithelial cells of the mucosa with schistosomiasis, colitis and the normal specimens. Cells of the colon carcinoma also showed no significant difference from those of the colon carcinoma associated with schistosomiasis. Atypical changes in the epithelial cells were not seen in the areas both adjacent to and remote from the carcinoma and in the egg deposit areas. Under LM, changes were manifested in various degrees in degeneration and disassociation of mucosal cells in colitis (1), schistosomiasis (1) and carcinoma associated with schistosomiasis (8). Under EM, changes in mucosal muscle cells were seen in colon carcinoma (2) and carcinoma associated with schistosomiasis (5). Proliferation of fibroblasts and hyperchromasia of the nuclei were noted in 3 cases of carcinoma associated with schistosomiasis. The pathological changes mentioned above were more prominent in cases of carcinoma associated with schistosomiasis than in those of colon carcinoma alone. The authors believed that the cause was non-specific changes induced by the toxin of the egg mechanical effects rather than a direct carcinogenic action of the eggs, and that the non-specific changes implied no direct relationship between the development of colon carcinoma and schistosomiasis.