[Electron microscopic study of mucus secretion in gastric carcinoma and its pathologic significance]

The genesis, ultrastructure and fate of mucin granule in cancer cells are described, and lysosomal degradation (crinophagy) was confirmed by demonstration of cytidine monophosphatase activity. Mucin granules usually appeared as those in the goblet cell, but were heterogenous. The chemical nature of mucin or the histogenesis of tumor should not be determined simply by depending on certain features of mucin granule, because these mucin granules might be influenced by the direction of cell differentiation, the maturity of mucin granule, and the abnormalities in its development. In this paper, different patterns of mucus secretion in various histologic types are described, and their pathologic significance is discussed.