[Comparative ultrastructure of the normal mucosa and the adenocarcinoma cells of the human large intestine].

This paper presents the comparative observation by transmission electron microscopy (TEM) of ten cases of adenocarcinoma of the large intestine and the normal colon mucosa. The ultrastructural features of the carcinoma cells were as follows: The basement membrane was perforated by cytoplasmic projections of the carcinoma cells, extending into the lamina propria. The membrane of the neighbouring cells was quite smooth, the interdigitation appeared sparse and the intercellular space was often dilated. The phenomenon of desmosome separation was found. Therefore, careful observation of the changes in the cell membrane is helpful in the diagnosis of colonic adenocarcinoma.