UNIQUE CYTOPLASMIC STRUCTURE IN PAPULAR HISTIOCYTOMA

[摘要] Intracytoplasmic granules with a unique and highly complex ultrastructure were observed within the cellular infiltrate of the lesions of 2 patients with papular histiocytoma. Examination of serial sections enabled construction of a 3 dimensional model of these granules, which appear to be composed of an elaborate arrangement of membranes and vesicles. Two hypotheses (endocytosis and exocytosis) are proposed for the mode of formation of these unique cytoplasmic structures.