High incidence of 17p13 chromosomal abnormalities in malignant histiocytosis

del(7q) in chronic B-cell lymphoid malignancies

Twelve patients with diagnosis of B-cell non-Hodgkin's lymphoma/leukemia and del[7q] were studied for their clinical, cytogenetic, and molecular characteristics. Eleven patients were classified as small cell lymphoma whereas one had a diffuse large cell lymphoma. Lymphoplasmacytic features were observed in six out of eleven small cell lymphomas. Morphologically and immunologically these small cell lymphomas could be classified as chronic lymphocytic leukemia (typical or atypical; 4 cases), marginal zone lymphoma (splenic lymphoma with villous lymphocytes; 1 case), mantle cell lymphoma (2 cases), or nonspecified, non-Hodgkin's lymphoma (4 cases). Eleven of twelve patients presented with peripheral blood and bone marrow involvement. Two of twelve cases showed del[7q] as the sole anomaly. Two different types of deletions were present: ten cases had del(7)(q21q31) and two cases had del(7)(q31q34). Cases that could be molecularly investigated did not show any involvement of BCL2, BCL3, or BCL6, and only one case had BCL1 rearrangement. The data indicate that del(7q) is associated with a subset of mature small B-cell lymphoproliferative disorders of which some but not all show lymphoplasmatic features.

A Case of Malignant Histiocytosis having Polyploid Clones Characterized by an Isochromosome of the Long Arm of Chromosome 17 [i(17q)] and t(9;22) Translocation

We report an interesting case of Malignant Histiocytosis (MH) with polyploid clones characterized by i(17q) and t(9; 22) translocation. A 47-year-old man had lymphadenopthy, splenomegaly and leukopenia at presentation. Bone marrow (BM) cytology showed 10.5% abnormal histiocytes. Karyotypic analyses with R- and G-banding techniques on BM cells revealed complex abnormalities: 88, XXYY, add(2) (p25), -4, -8, -11, i(17q), -21[4]/89, idem, t(9; 22) (q34; q11), +22[26]/46, XY [47], of which, t(9; 22) was confirmed by fluorescence in situ hybridization using a chromosome 22 paint wcp 22+. This patient was treated with interferon-alpha and COP regimen. 10 months later he achieved a complete hematologic and cytogenetic remission (CR). However, relapse occurred one year after achieving CR. At that time, cytogenetic examination showed a new polyploid clone characterized by add(1) (p36), add(2) (p25), -4, -8, t(9; 22), -11, i(17q), -21, +22 in addition to the other two polyploid clones observed previously. RT-PCR indicated that the BCR/ABL transcript (165bp) observed in classic chronic myeloid leukemia, was present, MH with t(9; 22) has not previously been described in the literature. This case may be the first one of MH with t(9; 22), and is likely a secondary event.

[Uni- and multifocal eosinophilic granulomas in adults. Diagnostic and therapeutic approaches. Apropos of 3 cases]

Unifocal and multifocal eosinophilic granuloma are Langerhans cell histiocytosis of unknown cause. Over the last 10 years, recent insights in pathogenesis and characterization of this pathology have been made. The authors report three cases of adult unifocal and multifocal eosinophilic granuloma. A review of literature underlines diagnostic features and therapeutic aspects of this disease.

Malignant histiocytosis: a reassessment of cases formerly classified as histiocytic neoplasms and review of the literature

Malignant histiocytosis (MH) and true histiocytic lymphoma (THL) are hematopoietic malignancies of the mononuclear phagocytic system distinguished from each other by clinical presentation and presumed cell of origin. THL present as a localized mass derived from the fixed tissue histiocyte which may or may not disseminate. MH originates from the circulating monocyte or tissue macrophage and is characterized by a syndrome of systemic symptoms, pancytopenia, adenopathy, hepatosplenomegaly, and wasting. The distinction between MH and THL is at times arbitrary and overlap exists between these syndromes. The clinicopathologic studies that defined these entities were performed prior to the development of immunophenotyping and other molecular techniques currently used to ensure proper classification of hematopoietic malignancies. Nine patients from the University of Minnesota originally diagnosed with MH were retrospectively analyzed using a panel of antibodies reactive against T cell, B cell, and myelomonocytic antigens. Only one patient was reclassified as a possible histiocytic malignancy after reevaluation. Similar immunophenotyping studies have also shown cases previously diagnosed as MH or THL express lymphoid antigens, and would now be classified as Ki-1 positive anaplastic large cell lymphoma (ALCL) or some other hematopoietic neoplasm. These results indicate true histiocytic neoplasms are extremely rare, and previous concepts concerning clinical presentation and therapeutic outcome of the entities are inaccurate. In this paper we summarize the results of multiple retrospective analyses of cases previously diagnosed as MH or THL, including our experience at University of Minnesota, to illustrate the overall rarity of these entities. The current literature on malignant histiocytic disorders is reviewed, and the clinical presentation of patients determined to have histiocytic malignancies using contemporary analytical techniques is discussed.

Bone marrow findings in malignant histiocytosis and/or malignant lymphoma with concurrent hemophagocytic syndrome

We examined bone marrow specimens from 19 patients with malignant histiocytosis (MH) and/or malignant lymphoma (ML) with concurrent hemophagocytic syndrome (HS) who suffered from high fever, hepatosplenomegaly, liver dysfunction, profound cytopenia, and erythrophagocytosis. There was little lymph-node enlargement or no tumor formation. The neoplastic cells in 3 patients exhibited histiocytes/macrophages phenotype with positive reactions for fluoride-sensitive nonspecific esterase, lysozyme and CD68 (KP1). Twelve other patients showed a T-cell (CD3) phenotype, in which 5 patients expressed CD30 (BerH2) as well. B-cell characteristics with CD20 (L26), CIg. nu lambda and gamma kappa were manifest in 2 patients, but indeterminate markers were found in the 2 remaining patients. Eighteen patients showed an infiltration of large neoplastic cells mainly with noncohesive interstitial growth pattern, ranging from 1.7% to 74.2% of the nucleated cells in the bone marrow. A large number of histiocytes/macrophages and dendritic cells was diffusely observed in 15 patients. Severely decreased hematopoiesis in all three series of hematopoietic cells was found in 16 patients. Bone marrow infiltration by the neoplastic cells and numerous reactive cells with erythrophagocytosis appears to be an important factor of profound cytopenia in patients of MH and/or ML with HS. The infiltrating pattern of the neoplastic and reactive cells in the bone marrow of MH and/or ML with HS was different from that of other types of peripheral T-cell ML, B-cell ML in high grade malignancy, and Hodgkin's disease. Cell characteristics and lineage of the neoplastic cells in MH and/or ML with HS are also discussed in this study.

A T-cell neoplasia showing clinicopathologic features of malignant histiocytosis with novel chromosomal abnormalities and N-ras mutation

Malignant histiocytosis (MH) is a distinct disease entity defined clinically and morphologically. However, the neoplastic origin of MH is not well established. The authors report a 26-year-old woman who showed the typical clinicopathologic features of so-called MH. Cytogenetic and molecular genetic examinations were performed in addition to the morphologic and immunologic approach. The expression of CD2 and T-cell receptor gene rearrangements indicated the T-cell origin of this case. CD30, which is positive for anaplastic large cell lymphoma (Ki-1 lymphoma), was not expressed. The cytogenetic study revealed a clonal chromosome abnormality involving 3q25, 6p21, 11p15, and 11q21. An N-ras point mutation within codon 12 (GGT----GCT) was also detected. These finding indicate that MH defined clinically and morphologically is not a tumor of true histiocytic origin and that it should be reclassified on the basis of immunologic, cytogenetic, and molecular genetic data.