1995 Volume 9 Issue 6 Pages 409-415
True malignant histiocytosis is rare and its cellular origin is still obscure. We reported two true cases of malignant histiocytosis with a review of the literature, and stress the cytogenetic aspects of this disorder. Case 1 was a boy, aged 11 months, diagnosed as having true malignant histiocytosis. Bone marrow cells which chiefly consisted of mature histiocytes that sometimes showed phagocytosis, and those chiefly consisted of histoblasts, had a similar chromosomal abnormality, 46, XX, -6, +mar. Surface marker analysis of the bone marrow cells showed was negative for T-cell and B-cell markers. Case 2 was a boy, aged 13 years, diagnosed as having true malignant histiocytosis. Blasts in the pleural fluid that showed phagocytosis did not have T-cell and B-cell markers, and showed clonal chromosomal abnormalities, 75 ?, XY, i (1q), der (12) t (1; 12) (q12; p13), add (12) (p13).We also reviewed the cytogenetic findings of previously reported cases with so-called malignant histiocytosis.2p 13 and 5q35 translocations, which have recently been suggested to be specific for Ki-1 lymphoma, 17p13 abnormalities, and hyperdiploidy (ploidy abnormalities) were frequently seen. Although various chromosomal abnormalities were seen, these findings showed cytogenetic heterogeneity of this disorder.
