muramidase and Mediastinal-Neoplasms

A 24-year-old Japanese man was admitted due to bloody phlegm in May 2002. A diagnosis of mediastinal germ cell tumor, mixed type involving seminoma, immature teratoma and embryonal carcinoma, was made by transthoracic needle biopsy. Three months later, his complete blood counts revealed pancytopenia with high fever. Examination of bone marrow revealed increased atypical large histiocytes (5.6%) with hemophagocytosis, and thus, hemophagocytic syndrome related to germ cell tumor was diagnosed. In addition, chromosomal analysis of the bone marrow cells revealed a 47, XY, +9 genotype. Chemotherapies for germ cell tumor and hemophagocytic syndrome were performed without any improvement, and he died of diffuse alveolar damage. Autopsy revealed diffuse infiltration of immature histiocytes with hemophagocytosis in the liver, spleen and bone marrow. The atypical histiocytes were positive for CD68 and lysozyme and negative for lymphoid markers, and the diagnosis of true malignant histiocytosis associated with mediastinal germ cell tumor was made. The rare chromosomal abnormality of trisomy 9, a marker for benzene-related leukemia, was seen in the present case without apparent benzene exposure.

Topics: Adult; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Biopsy, Needle; Bone Marrow; Chromosomes, Human, Pair 9; Histiocytes; Histiocytic Sarcoma; Humans; Japan; Liver; Lymphohistiocytosis, Hemophagocytic; Male; Mediastinal Neoplasms; Muramidase; Neoplasms, Germ Cell and Embryonal; Neoplasms, Second Primary; Pulmonary Alveoli; Time Factors; Treatment Failure; Trisomy

A myeloid cell line, designated PL-21, was established from the peripheral blood of a patient with acute promyelocytic leukemia. The PL-21 cell line grew in single-cell suspension, with a doubling time of 48-64 hr, and consisted of promyelocytes with fine immature nuclei and prominent azurophilic granules in the cytoplasm. PL-21 cells were positive for peroxidase, naphthol AS-D chloroacetate esterase, and Sudan Black B staining. Under the usual culture conditions, a small proportion of these cells differentiated into mature granulocytes, and this differentiation was enhanced by the addition of dimethyl sulfoxide in the culture medium. PL-21 cells had receptors for the Fc portion of IgG and complement, intracytoplasmic lysozyme and phagocytic activity, but lacked Epstein-Barr virus-associated nuclear antigen. Chromosome analysis of this cell line revealed a human male polyploid karyotype with 13q+ and double minute chromosomes. This new myeloid cell line may provide useful material for the study of proliferation and differentiation of human leukemia cells.

Topics: Adult; Cell Differentiation; Cell Line; Cells, Cultured; Dimethyl Sulfoxide; Humans; Immunoenzyme Techniques; Karyotyping; Leukemia, Myeloid, Acute; Leukocytes; Male; Mediastinal Neoplasms; Muramidase; Phagocytosis; Rosette Formation