Electron-microscopic study of the villous adenoma of the colon.

The author studied the electron-microscopic peculiarities of villous adenoma as illustrated by 12 cases. She found that the dominant cells of villous adenoma are undifferentiated epithelial cells. Electron-microscopic signs of malignant transformation were revealed by nuclear changes, by the changes in the cytoplasmic membrane and by the immaturity of cells. Leuchtenberger's inclusion bodies are assumed to develop by herniation of cytoplasmic processes of immature tumour cells. In one tumour associated with electrolyte loss, atypical cells were observed with an electronmicroscopic picture indicative of an intense secretory activity. However, the secretion drops differed from the normal mucus drops of the mature goblet cells of the colonic mucosa. The author believes it to be possible that the tumour cells of atypical morphological appearance secrete mucus of abnormal composition which could be responsible for the syndrome of electrolyte loss.