Abstract: | The analysis of peculiarities of clinical course and morphology of malignant (acute) histiocytosis in 50 pediatric patients made a case for identification of the disease as separate pathology of histiocytic sarcoma type. Clinical course features include: lymphadenopathy, involvement of bones and--less frequently--lungs, skin and subcutaneous fat, marked fever and weight loss. Cytologic and histologic examination show polymorphic tumor cells of varying degree of differentiation, with blasts predominating. Well-developed Golgi complex, presence of lysosomes, phagosomes and erythrophagocytosis are among the characteristic ultrastructural features of the disease. |