Abstract
Liver biopsy was performed under laparoscopic observation of our 24 cases of sarcoidosis. Noncaseating epithelioid cell granulomas were histologically demonstrated in the liver biopsy specimens in 20 cases (83%). Ten cases were examined by electron microscope. Ultrastructurally, epithelioid cell granulomas consisted of four cell type: epithelioid cells (large and small mononuclear epithelioid cells and multinuclear giant cells), histiocyte-like cells, lymphocytes and fibroblasts. Epithelioid cells seemed to be highly active cells with abundant cytoplasmic organelles: large amounts of Golgi apparatus, dense vacuoles of varing sizes and numerous mitochondria. It was peculiar not to find lysosomes in the cytoplam. Elongated cytoplasmic processes had developed an interdigitating cytoplasmic processes. Multinuclear giant cells were assumed to be formed by the fusion of large mononuclear epithelioid cells. Because of the presence of lysosomes in the cytoplasm, histiocyte-like cells were thought to be phagocytized type of highly active cells. Intermediate cells between histiocyte-like cells and epithelioid cells were not ultrastructurally evident in epithelioid cell granulomas in the liver.
