Search

Objective: To examine effects of a common mutation (2-base insertion in exon 5) of the TP53 gene on biological function of p53 protein in canine histiocytic sarcoma cells., Sample: Canine histiocytic tumor cell lines DH82 with deletion of TP53 and CHS-3 with the wild-type TP53 and canine wild-type and mutant TP53 fragments., Procedures: Wild-type or mutant TP53 with a polyprotein peptide tag at the N-terminus was transduced into DH82 and CHS-3 cells. Expression of p53 protein, changes in function as a transcription factor, and susceptibility to doxorubicin and nimustine were compared., Results: Transduced p53 protein was detected in wild-type TP53 -transduced DH82 and CHS-3 cells, whereas expression was not detected in mutant TP53 -transduced cells. There were significant increases in expression of target genes of p53 protein, including p21 and MDM2 , in wild-type TP53 -transduced cells, compared with results for native and mock-transfected cells, but not in mutant TP53 -transduced cells. There was no significant difference in drug susceptibilities among native and derivative cells of CHS-3. However, cell viabilities of wild-type TP53 -transduced DH82 cells incubated with doxorubicin were significantly lower than viabilities of native, mock-transfected, and AT insertion mutation- TP53 -transduced DH82 cells; susceptibility to nimustine did not differ significantly among cells., Conclusions and Clinical Relevance: Expression of p53 protein and its function as a transcription factor were lost after addition of a 2-base insertion in the TP53 gene in canine histiocytic tumor cells. Additional studies are needed to investigate the clinical relevance of this mutation in histiocytic sarcomas of dogs.

A 7-year-old female domestic rabbit suffered from labored respiration, poor appetite, mild anemia and thrombocytopenia. Radioscopic examination revealed masses in multiple locations including the intrapleural cavity and spleen. Forty-three days after the first visit to a private veterinary clinic, the rabbit died of severe respiratory distress. Microscopically, all of the masses were composed of round to polygonal neoplastic cells with distinct cell borders that were arranged in a sheet pattern. Multinucleated giant neoplastic cells were often observed. Some neoplastic cells had phagocytozed one or more erythrocytes. Immunohistochemical staining revealed that the neoplastic cells expressed vimentin, CD204, Iba-1 and lysozyme, but not CD163. Based on the morphological and immunohistochemical findings, this case was diagnosed as disseminated histiocytic sarcoma with hemophagocytosis.

Histiocytic sarcoma is a rapidly progressive and fatal neoplastic disease in dogs. It is unclear whether costimulatory molecules, including CD28, cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), and programmed death-1 (PD-1), are expressed on peripheral blood lymphocytes (PBLs) of canine patients with histiocytic sarcoma. The objective of this study was to evaluate the expression of CD28, CTLA-4, and PD-1 molecules on PBLs of patients with histiocytic sarcoma, patients with other tumors, and healthy controls. Twenty-six dogs were included in the study, with eight, ten, and eight dogs in the histiocytic sarcoma, other tumor, and healthy control groups, respectively. PBLs and serum were prospectively obtained from patients diagnosed histopathologically with histiocytic sarcoma, other tumors and healthy controls. The surface expression of CTLA-4, CD28, and PD-1 on T lymphocytes was examined using flow cytometric analysis. Serum samples were frozen at -30°C until serum interferon-γ (IFN-γ) was measured by enzyme-linked immunosorbent assay. The expression level of CTLA-4 on CD4+ lymphocytes was significantly higher in the histiocytic sarcoma group than in the control group. The expression of CTLA-4 on CD8+ lymphocytes was significantly higher in the histiocytic sarcoma group than in the other two groups. In addition, the expression of PD-1 on CD8+ lymphocytes was significantly higher in the histiocytic sarcoma group than in the control group. However, no significant differences in CD28 expressions and serum IFN-γ levels were observed. The present results provided evidence showing that the expression levels of CTLA-4 on both CD4+ and CD8+ lymphocytes and PD-1 on CD8+ lymphocytes in peripheral blood obtained from dogs with histiocytic sarcoma were upregulated. The overexpressions of CTLA 4 and PD-1 suggested that antitumor immunity may be suppressed in dogs with histiocytic sarcoma.

Introduction: Histiocytic sarcoma (HS) of the central nervous system (CNS) is exceptionally rare in pediatric patients, historically associated with an exceptionally poor prognosis. Here, the authors present a novel case of protracted progression-free survival following surgical excision, radiotherapy and temozolomide., Case Report: A 15-year-old Caucasian girl presented with a two-month history of headache, diplopia, vomiting, lethargy, weight loss and neurocognitive deterioration without gross neurological deficit on physical examination. Magnetic resonance imaging (MRI) of the brain identified a 5.8 × 4.7 × 4.0 cm lesion in the right frontal lobe with associated mass effect and no dissemination. Following two surgical procedures, gross total resection was achieved. Histology and immunohistochemistry confirmed HS, with strong CD163 staining. After focal radiotherapy with concomitant temozolomide, and a further seven cycles of temozolomide, the patient made an excellent recovery and is recurrence free without neurological deficit, 23 months following presentation., Conclusion: To the authors' knowledge, this is the first incidence of a prolonged, functionally preserved and recurrence-free outcome following a diagnosis of HS within the CNS of a pediatric patient. We suggest early diagnosis prior to dissemination and complete surgical resection as an essential treatment goal in this rare disease.

This report of an 82-year-old man who presented with a 3-week history of an enlarging left axillary mass and mild fevers, highlights the usefulness of both gallium-67 and F-18 FDG PET/CT imaging in the staging of histiocytic sarcoma. While PET/CT was superior in determining the extent of the disease, gallium can be used to help stage the disease in centers where PET/CT is not available.

Background: Histiocytic malignancies in both humans and dogs are rare and poorly understood. While canine histiocytic sarcoma (HS) is uncommon in the general domestic dog population, there is a strikingly high incidence in a subset of breeds, suggesting heritable predisposition. Molecular cytogenetic profiling of canine HS in these breeds would serve to reveal recurrent DNA copy number aberrations (CNAs) that are breed and/or tumor associated, as well as defining those shared with human HS. This process would identify evolutionarily conserved cytogenetic changes to highlight regions of particular importance to HS biology., Methods: Using genome wide array comparative genomic hybridization we assessed CNAs in 104 spontaneously occurring HS from two breeds of dog exhibiting a particularly elevated incidence of this tumor, the Bernese Mountain Dog and Flat-Coated Retriever. Recurrent CNAs were evaluated further by multicolor fluorescence in situ hybridization and loss of heterozygosity analyses. Statistical analyses were performed to identify CNAs associated with tumor location and breed., Results: Almost all recurrent CNAs identified in this study were shared between the two breeds, suggesting that they are associated more with the cancer phenotype than with breed. A subset of recurrent genomic imbalances suggested involvement of known cancer associated genes in HS pathogenesis, including deletions of the tumor suppressor genes CDKN2A/B, RB1 and PTEN. A small number of aberrations were unique to each breed, implying that they may contribute to the major differences in tumor location evident in these two breeds. The most highly recurrent canine CNAs revealed in this study are evolutionarily conserved with those reported in human histiocytic proliferations, suggesting that human and dog HS share a conserved pathogenesis., Conclusions: The breed associated clinical features and DNA copy number aberrations exhibited by canine HS offer a valuable model for the human counterpart, providing additional evidence towards elucidation of the pathophysiological and genetic mechanisms associated with histiocytic malignancies. Extrapolation of data derived from canine histiocytic disorders to human histiocytic proliferation may help to further our understanding of the propagation and cancerization of histiocytic cells, contributing to development of new and effective therapeutic modalities for both species.

Three dogs (two Rottweilers and a Flat-coated retriever) showed various neurological signs, including apathy, depression, circling, a partial decrease in functions associated with cranial nerves, seizures, hyperaesthesia, proprioceptive deficits, and increased spinal reflexes. In all three cases, necropsy revealed a solid, distinct, white mass in the brain and multiple, poorly demarcated, firm nodular proliferations in the lung; in one case the liver was also affected. Histopathological examination showed loosely aggregated, pleomorphic cells, with abundant eosinophilic cytoplasm. The neoplastic cells sometimes contained vacuoles or phagocytized cells. Binucleated and multinucleated giant cells, and mitotic figures, were common. Immunohistochemically, the tumour cells reacted strongly for lysozyme and vimentin, but there was no reaction for S-100 protein, cytokeratin, CD3 or CD79a. The histological and immunohistochemical examinations indicated a histiocytic origin of the tumour cells and malignant histiocytosis was therefore diagnosed.

A 3-year-old boy with multiple sulphatase deficiency, complicated by a haemophagocytic syndrome, recovered with conventional treatment. Haemophagocytic syndrome can be a complication of many disorders including metabolic diseases, frequently triggered by intracellular viral and bacterial infections or even by drug administration.

Although myelomonoblastic leukemia is thought to originate from a malignant transformation of the stem cell of the mononuclear phagocyte system, malignant histiocytosis (MH) is classically assumed to represent a malignant change of the terminal and fixed elements of this system. Indeed, MH is characterized by the proliferation of large, clear, pleomorphic, "histiocytic-like" HLADR and CD30+ cells resulting in a nodal and extranodal disseminated neoplasm affecting preferentially and severely children and young adults. Although there is broad agreement on the clinicopathologic presentation of this condition, there is currently quite a controversy over the T-lymphoid or histiocytic origin of the proliferative cells that results in a nosologic discussion between the anaplastic large cell lymphoma (ALCL) advocates and the MH supporters. This article has dealt mainly with this nosologic discussion and with the contributions provided by the investigations performed on MH permanent cell lines. These in vitro studies have demonstrated that the proliferation is characterized by a unique chromosomal abnormality, the 5q35bp usually associated with a t(2;5) translocation generating a fusion gene NPM/ALK and the subsequent translation of p80 protein. Although it is known that no single chromosomal abnormality is strictly restricted to a cell lineage, this 5q35bp and associated translocations seem today to represent the hallmark for this condition. In view of these chromosomal aberrations, the CD30+ ALCLs represent a heterogeneous group because 15% to 50% express the NPM/ALK fusion gene. In addition, these in vitro investigations have shown that 5q35bp proliferative cells are glass-adherent, can develop an immunodependent phagocytosis, and are able to reduce NBT and produce TNF-alpha. More significantly, they express constitutively the c-fms (the receptor of the macrophage growth factor) and, under TPA stimulation, are able to modulate the expression of this receptor and its ligand, as well as TNF-alpha and IL-1. None of these cell lines express CD3, but several express CD68 and CD71. In contrast, genomic investigations have shown the underlying existence of monoallelic and even biallelic gene rearrangements for TCR beta and IgJH. In view of these discrepancies between the genomic and phenotypic features of these cells, the histogenetic debate should remain open but must take into account these new chromosomal and molecular data.

Malignant histiocytic disorders, other than leukemias, are extremely rare in childhood. Despite unresolved nosologic and terminologic difficulties, they should be classified according to the lineage of the aberrant cells in a given tumor. There are no common and typical clinical presentations, nor are there established treatment modalities available. For the disseminated forms, aggressive systemic treatment modalities--similar if not identical to those used for large cell anaplastic lymphomas--appear to be the best treatment option. For the localized forms, which are primarily dendritic cell sarcomas, a more localized and individualized therapy is appropriate.

Objective: To observe the efficacy and side effects of allogeneic bone marrow transplantation (allo-BMT) in the treatment of malignant histiocytosis (MH)., Methods: After conditioning with chemotherapy and total body irradiation, HLA-A, B, DR, DQ compatible allo-BMT was performed in a patient with MH., Results: DNA fingerprinting showed engraftment on day 22, bone marrow aspiration showed hypercellularity on day 50, and no abnormal cell was found. The patient developed acute graft-versus-host disease ( II degrees) on day 40 and herpes zoster 6 months post-transplantation, and the patient has survived disease-freely for 24 months after allo-BMT., Conclusion: This is the first report of treatment of MH with allo-BMT in China, showing that allo-BMT may significantly prolong the survival of MH.

Malignant histiocytosis, as defined by Rappaport, is now known as a manifestation of malignant lymphoma, the majority of which is the T-cell type. However, unlike the typical presentation of most non-Hodgkin lymphomas, this condition presents with atypical features mimicking acute hepatitis or infectious mononucleosis. The latter diagnosis is often made because of the occurrence of atypical mononuclear cells on the peripheral blood films. This is clearly seen in the seven patients we report where the initial diagnoses were that of viral fever or hepatitis. Some characteristics were found in these patients to differentiate the condition from infectious mononucleosis (IMS) and acute hepatitis (AH): paucity of lymph nodes, cholestasis and prolonged prothrombin time (PT) which is atypical IMS; persistent fever, thrombocytopaenia and disproportionately high aspartate aminotransferase which is unusual in AH in the absence of any drug or alcohol history. The PT is the most important prognosis factor. Early diagnosis and treatment led to improved survival in an otherwise aggressive and rapidly fatal condition.

A 53-year-old woman was admitted with fever and general fatigue in December, 1988. A diagnosis of malignant histiocytosis (MH) was made based on her high level of LDH, thrombocytopenia, mild splenomegaly without systemic lymphadenopathy. There was also bone marrow infiltration large atypical cells and erythro-phagocytosis. VEPA therapy resulted in complete remission. Visual disturbance and left lagophthalmos were recognized in March 1990. These signs indicated central nervous system (CNS) relapse which disappeared after intrathecal methotrexate injection. The same symptoms and signs appeared after another, 5 months. Tumor cells were found not only in the central spinal fluid but also in bone marrow. CNS and bone marrow recurrence were treated with intrathecal methotrexate injection VEPA therapy and cranial irradiation. We diagnosed this case as MH, based on the clinical features which did not include systemic lymphadenopathy and laboratory findings although TcR-gamma rearrangement was observed in bone marrow cells. Only one case of CNS infiltration diagnosed when alive has previously been reported in Japan. We report here a very rare case in which by medical treatment CNS infiltrations was improved twice.

The authors report a case of acute myeloblastic leukemia in which erythrophagocytosis by the leukemic cells was so extensive as to mimic malignant histiocytosis at postmortem. It is postulated that premature expression of phagocytic function in leukemic cells and disseminated intravascular coagulopathy, which accompanied the initial clinical presentation, explained the unusually prominent erythrophagocytosis.

Diagnosis of malignant histiocytosis (MH) often resembles the solving of an intricate puzzle consisting of clinical symptoms such as lymphadenopathy, splenomegaly, fatigue, fever, and rapid progression, and hematopathological findings such as the presence of atypical histiocytes, especially in blood and bone marrow smears. The lack of one or more of these criteria may greatly impede diagnosis, as in the case of a 45-year-old male with an unusual hematopathological manifestation of MH. The major clinical findings included panhemocytopenia, splenomegaly, and signs of liver dysfunction with severe jaundice. During life, a definite diagnosis could not be established. Histological and cytological evaluation of the spleen following splenectomy revealed a marked increase in histiocytes/macrophages with pronounced hemophagocytosis. These findings were interpreted as a (benign) hemophagocytic syndrome, possibly related to a viral infection. Extensive serological investigations, however, furnished no evidence of a so-called virus- or infection-associated hemophagocytic syndrome. The patient died 5 months after the onset of disease with symptoms of progressive liver failure. Meticulous histological examination of bone marrow revealed a few patchy tumorous infiltrates consisting of dense pleomorphic histiocytes. Thus, a diagnosis of MH was established. This case of MH was unusual with particular regard to its pronounced hemophagocytosis, slight cytological atypia of the histiocytes, and absence of infiltration of lymph nodes.

Ten children, four males and six females, with malignant histiocytosis were treated from July 1980 to July 1984. None of them had an affected sibling with a similar disorder. Septic-type fever, hepatosplenomegaly, lymphadenopathy, pulmonary infiltration, and disseminated intravascular coagulation were common signs and symptoms, and convulsion occurred in four cases. The diagnosis was made from bone marrow smears in all cases. In five cases, biopsy or autopsy specimens confirmed the diagnosis. In five cases studied, proliferating histiocytes in lymph nodes were demonstrated to be S100 protein-positive. All patients were treated with adriamycin, cyclophosphamide, vincristine, and prednisone (ACOP). Complete response was achieved in four patients after two to three courses of ACOP, and another case attained complete remission after further drug treatment. The five complete responders are now alive without evidence of disease after 23-48 months from the onset. Among partial and no responders, four died within 3 months and one has been alive with disease for 2 months. Bone marrow aspiration is useful for prompt diagnosis, and early treatment with intensive combination chemotherapy improves the prognosis of malignant histiocytosis in childhood.

The hematopoietic disregulation in adult mice induced by the malignant histiocytosis sarcoma virus (MHSV) and the Harvey murine sarcoma virus (Ha-MuSV), which both possess c-Ha-ras-related oncogenic sequences, was investigated. Spleen focus formation induced by MHSV and Ha-MuSV was not restricted by the Fv-2 resistance locus in congenic DDD and C57BL/6 mice, unlike leukemogenesis induced by Friend virus, Rauscher virus, and the myeloproliferative sarcoma virus (MPSV). C57BL/6 mice were much more resistant to MHSV and Ha-MuSV-induced spleen focus formation than DDD mice regardless of their Fv-2 state. Infection of DDD mice with MHSV caused a systemic histiocytic neoplasia, best described as murine malignant histiocytosis. Transformed histiocytic cells proliferated excessively in the bone marrow, spleen, and lymph nodes and, in the final stages of the disease, in all major parenchymal organs. The Ha-MuSV caused a strikingly different benign histiocytic tumor in DDD mice and, unlike MHSV, did not induce a rapid, progressive splenomegaly in C57BL/6 mice. Infection of DDD mice with MHSV induced a rapid and synchronized depletion of early and late erythroid precursor cell pools. In MHSV-infected C57BL/6 mice comparable changes were observed with dissimilar kinetics. Macrophage colony-forming cells of MHSV-infected mice were increased in number and proliferated independently of stimulating growth factors. The disease induced by MHSV in mice can thus serve as a model for malignant histiocytosis in humans.