[The morphological characteristics of hepatocyte dysplasia]

27 liver biopsies of patients with chronic hepatitis and liver cirrhosis of viral etiology were studied histologically, electron microscopically and morphometrically. Hepatocyte dysplasia is characterized by the disturbance of the liver lobule structure and alteration of the liver tissue regeneration. Dysplasia is manifested light microscopically by the three types of cells: large, "average" and small ones. Electron microscopically (EM) 4 varieties of dysplastic hepatocytes can be distinguished: (1) with developed cytoplasmic network, (2) with hyperplasia of mitochondria, (3) with underdeveloped organelles, (4) with highly atypical nuclei. There exists a correlation between the light microscopic and EM types of dysplasia: the 1st and the 2nd types are typical for the "average" cell dysplasia, the 3rd for the large cell and the 4th for the small cell dysplasia. The latter two ultrastructural varieties can be considered as manifestations of severe dysplasia. One of them is characterized by the large size of cells, the presence of two or three nuclei, nucleus-cytoplasmic ratio 0.3-0.4 and pronounced signs of atypical ultrastructural organization in the form of the underdevelopment and deformity of the cytoplasmic network and mitochondria. Another variety of dysplastic hepatocytes is represented by small basophilic cells with hyperchromic deformed nuclei, high nucleus-cytoplasmic ratio (greater than 0.4) and the signs of lowering the differentiation/underdevelopment of the granular cytoplasmic network, ribosome hyperplasia, the absence of the mature intercellular contacts.