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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previously diagnosed cases of hepatosinusoidal T-cell lymphoma and malignant histiocytosis (MH) may include lymphoid neoplasms of natural killer (NK) cell lineage associated with Epstein-Barr virus (EBV). Such hepatosinusoidal neoplasms were found to demonstrate hepatomegaly but not lymphadenopathy, and all were diagnosed by a liver biopsy. Sixteen adult patients diagnosed with hepatosinusoidal leukaemia/lymphoma (six NK-cell leukaemia/lymphomas [NKLLs], five instances of MH, three T-cell malignant lymphomas [T-MLs], and two adult T-cell leukaemia/lymphomas [ATLLs] were examined for EBV by in situ hybridization, then were studied immunohistochemically and subjected to a DNA analysis. Among our five patients with MH, neoplastic cells showed T-cells, but no histiocytic markers, and they were considered to have either a T-cell or NK-cell lineage. All NKLLs, MHs and T-MLs, except for ATLLs accompanied by reactive hemophagocytic histiocytes, varied in number in each case. In situ hybridization revealed the presence of EBV in the nuclei of atypical cells in all of the six lymphoid neoplasms of NK-cell lineage. Each case of MH and each T-ML which represented EBV demonstrated no definite T-cell or histiocytic markers. Patients with ATLL did not reveal EBV. In all patients with hemophagocytosis, EBV was present in the nuclei of the neoplastic lymphocytes, but not in the hemophagocytic cells. Finally, the 16 cases were reclassified into eight cases with EBV-containing NKLLs, six T-MLs, and two ATLLs. In addition, no true histiocytic neoplasms were observed. The mechanism of hemophagocytosis may be therefore the production of lymphokines (macrophage-activating factors) by neoplastic lymphocytes. EBV-associated hepatosinusoidal leukaemia/lymphoma may thus contain a lymphoid neoplasm of NK-cell lineage, which made it difficult to be distinguished from the previously designated malignant histiocytosis.
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PMID:Hepatosinusoidal leukaemia/lymphoma consisting of Epstein-Barr virus-containing natural killer cell leukaemia/lymphoma and T-cell lymphoma; mimicking malignant histiocytosis. 779 96

Expression of the natural killer (NK) cell antigen CD56 is uncommon among lymphomas, and those that do are almost exclusively of non-B-cell lineage and show a predilection for the nasal and nasopharyngeal region. This study analyzes 49 cases of nonnasal CD56+ lymphomas, the largest series to date, to characterize the clinicopathologic spectrum of these rare neoplasms. All patients were Chinese. Four categories could be delineated. (1) Nasal-type NK/T cell lymphoma (n = 34) patients were adults 21 to 76 years of age (median, 50 years), including 25 men and 9 women. They presented with extranodal disease, usually in multiple sites. The commonest sites of involvement were skin, upper aerodigestive tract, testis, soft tissue, gastrointestinal tract, and spleen. Only 7 cases (21%) apparently had stage I disease. The neoplastic cells were often pleomorphic, with irregular nuclei and granular chromatin, and angiocentric growth was common. The characteristic immunophenotype was CD2+ CD3/Leu4- CD3epsilon+ CD56+, and 32 cases (94%) harbored Epstein-Barr virus (EBV). Follow-up information was available in 29 cases: 24 died at a median of 3.5 months; 3 were alive with relapse at 5 months to 2.5 years; and 2 were alive and well at 3 and 5 years, respectively. (2) Aggressive NK cell leukemia/lymphoma (n = 5) patients presented with hepatomegaly and blood/marrow involvement, sometimes accompanied by splenomegaly or lymphadenopathy. The neoplastic cells often had round nuclei and azurophilic granules in the pale cytoplasm. All cases exhibited an immunophenotype of CD2+ CD3/Leu4- CD56+ CD16- CD57- and all were EBV+. All of these patients died within 6 weeks. (3) In blastoid NK cell lymphoma (n = 2), the lymphoma cells resembled those of lymphoblastic or myeloid leukemia. One case studied for CD2 was negative and both cases were EBV-. One patient was alive with disease at 10 months and one was a recent case. (4) Other specific lymphoma types with CD56 expression (n = 8) included one case each of hepatosplenic gammadelta T-cell lymphoma and S100 protein+ T-cell lymphoproliferative disease and two cases each of T-chronic lymphocytic/prolymphocytic leukemia, lymphoblastic lymphoma, and true histiocytic lymphoma. All of these cases were EBV-. Six patients died at a median of 6.5 months. Nonnasal CD56+ lymphomas are heterogeneous, but all pursue a highly aggressive clinical course. The nasal-type NK/T-cell lymphoma and aggressive NK cell leukemia/lymphoma show distinctive clinicopathologic features and a very strong association with EBV. Blastoid NK cell lymphoma appears to be a different entity and shows no association with EBV.
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PMID:Nonnasal lymphoma expressing the natural killer cell marker CD56: a clinicopathologic study of 49 cases of an uncommon aggressive neoplasm. 919 74

The classification of natural killer (NK)-cell and NK-like T-cell malignancies has undergone significant evolution in recent years. Although examples of NK-cell tumors resembling acute leukemia have been described anecdotally as blastic, blastoid, or monomorphic NK-cell leukemia/lymphoma (NKL/L), the clinical and pathologic features of these tumors have not been systematically defined. We report four patients with blastic NKL/L and describe the clinical, pathologic, and immunophenotypic findings in these cases. All patients were elderly (58-82 years) and presented with cutaneous plaques. Two patients also had adenopathy, and three patients had marrow involvement at presentation. Biopsy of cutaneous lesions showed atypical superficial and deep dermal lymphoid infiltrates. Involved lymph nodes were architecturally effaced by an interfollicular infiltrate with blastic cytologic features. In Wright-Giemsa-stained blood or marrow smears, tumor cells had finely distributed nuclear chromatin, many with nucleoli, and variable amounts of cytoplasm. In contrast to many NK and NK-like T-cell disorders, azurophilic cytoplasmic granules were absent or inconspicuous. The tumor cells were immunophenotypically distinctive. They expressed intermediate density CD45, as is characteristic of blasts; in addition, the cells were positive for HLA-DR, CD2, CD4, and the NK-associated antigen CD56. Surface CD3, cytoplasmic CD3, and CD5 were negative in all cases tested, whereas CD7 was expressed in two cases. In formalin-fixed tissue, tumor cells marked with antibodies to CD43, but not with other T- or B-lineage-related antibodies. All three cases studied for Epstein-Barr viral RNA by in situ hybridization were negative. Although treatments varied, all three patients with clinical follow-up died within months of the diagnosis. The clinical course in two patients culminated in an overtly leukemic phase. These findings suggest that blastic NKL/L represents a distinct clinicopathologic entity, characterized by cutaneous, nodal, and marrow involvement by blastic cells with immunophenotypic characteristics of true NK cells. The disease afflicts elderly patients, pursues an aggressive course, and may culminate in overt leukemia.
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PMID:Blastic natural killer cell leukemia/lymphoma: a clinicopathologic study. 1043 71

We studied the morphologic and immunohistochemical features of 10 peripheral T-cell lymphomas of a cytotoxic phenotype (CD3+/CD4-/CD8+), encountered among 98 peripheral T-cell lymphomas (PTCLs). Nine tumors were positive for both cytotoxic molecules, namely perforin (Pf) and granzyme B (GrB), and strong positivity was seen in the majority of the malignant cells. We also studied the expression of these molecules in 92 other cases of T-cell and natural killer (NK) cell neoplasms; 18 anaplastic large cell lymphomas (ALCLs); 63 CD4+ PTCLs; 10 CD56+ nasal lymphomas; and 1 NK-cell leukemia. Most of the CD4+ PTCLs (62 of 63) were negative for GrB, but all of the nasal lymphomas and the NK cell leukemia were positive for both Pf and GrB. Variable expression was seen among the 18 ALCLs. Within the 10 CD8+ PTCLs, 4 involved the skin, 3 of which were diagnosed as primary cutaneous lymphomas. Five patients died within 1 year of diagnosis. According to the Revised European-American Classification of Lymphoid Neoplasms, seven cases were categorized as "PTCL, unspecified," and three as "angioimmunoblastic T-cell lymphoma," "adult T-cell lymphoma/leukemia," or "small cell lymphoma," respectively. Three cases had characteristic morphologic features consisting of large lymphomatous cells with massive necrosis and nuclear fragmentation. Epstein-Barr virus mRNA was detected by in situ hybridization in three cases. Although the degree of apoptosis varied, apoptotic cells were detected in all cases by terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate-biotin nick end labeling. We conclude that CD8+ PTCLs are relatively rare, often involve extranodal sites, have an aggressive clinical course, and are often associated with Epstein-Barr virus. Compared with ALCLs, which have recently been considered as neoplasms of cytotoxic T-cells, we think that CD8+ PTCLs are more lineage-specific neoplasms of mature, cytotoxic, T lymphocytes.
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PMID:Perforin and granzyme expression in cytotoxic T-cell lymphomas. 957 80

We describe a 74-year-old woman with the diagnosis of natural killer (NK)-cell leukaemia and autoimmune pathology. Four years previously, a diffuse large B cell non-Hodgkin's lymphoma had been diagnosed and treated effectively. Although NK-cell leukaemia has been thought to be a distinct highly aggressive clinicopathological entity, our case shows no further evolution at the present time. As far as we know, this association has not been previously described in the literature.
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PMID:Natural killer (NK) cell leukaemia in a patient with a B cell non-Hodgkin's lymphoma. 1079 3

In the normal developmental pathway of natural killer (NK) cells, pre-NK cells express CD161, immature NK cells express CD161 and CD56, and mature NK cells express CD161, CD56 and CD94. To identify the normal counterpart of NK cells from which neoplastic cells originate, surface antigens were analysed. Blastic NK-cell lymphoma/leukaemia lacked CD94 and CD161 but had CD56. Aggressive NK-cell leukaemia/lymphoma and nasal NK-cell lymphoma, although morphologically immature, expressed both CD56 and CD94 and strong NK activity. Cells from chronic NK lymphocytosis expressed CD56 and CD94.
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PMID:Differentiation stage of natural killer cell-lineage lymphoproliferative disorders based on phenotypic analysis. 1172 37

Blastic natural killer (NK)-cell leukemia/lymphoma is a neoplasm of NK origin with aggressive behavior. The disease affects mainly elderly people and often presents with skin lesions and overt leukemia. Blastic morphology, an NK-cell immunophenotype, and lack of association with Epstein-Barr virus are the clues for the diagnosis. We report herein, the case of a patient with a blastic NK-cell leukemia/lymphoma with overt leukemia at diagnosis, who achieved a complete response after CHOP (cyclophosphamide/doxorubicin/vincristine/prednisone) chemotherapy. However, the patient relapsed a few months later and died due to disease progression. Cases of blastic NK-cell leukemia/ lymphoma previously reported are briefly reviewed.
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PMID:Blastic natural killer cell leukemia/lymphoma presenting as overt leukemia. 1177 95

Natural killer (NK) cell neoplasms, which include extranodal NK/T-cell lymphoma (nasal and extranasal) and aggressive NK cell leukemia, are generally rare, but they are more common in people of Oriental, Mexican and South American descent. These neoplasms are highly aggressive, and show a strong association with Epstein-Barr virus. Extranodal NK/T-cell lymphoma most commonly affects the nasal cavity and other mucosal sites of the upper aerodigestive tract. Patients present with nasal obstruction or midfacial destruction. Despite the early stage of disease at presentation, overall survival is poor. Patients with the extranasal form of the lymphoma often present with high-stage disease, commonly involving the skin, gastrointestinal tract, testis, and soft tissue, and the prognosis is even worse. Histologically, the lymphoma can show a broad cytologic spectrum, but apoptosis, necrosis, and angioinvasion are common. The most common immunophenotype is CD2(+), surface CD3(-), cytoplasmic CD3(+), CD56(+). Based on currently available data, treatment of nasal NK/T-cell lymphoma should consist of radiotherapy, with or without multiagent chemotherapy. More research is required to ascertain the role of high-dose chemotherapy with stem cell rescue and that of non-multidrug resistance-related chemotherapeutic agents. Aggressive NK cell leukemia affects younger patients, who present with poor general condition, fever, and disseminated disease; they often die within a short time from systemic disease or complications such as multi-organ failure. The peripheral blood and bone marrow show atypical large granular lymphocytes, which exhibit an immunophenotype similar to that of extranodal NK/T-cell lymphoma. Aggressive NK cell leukemia must be distinguished from T-cell large granular lymphocyte leukemia and indolent NK cell lymphoproliferative disorder, both of which are indolent.
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PMID:Natural killer cell neoplasms: a distinctive group of highly aggressive lymphomas/leukemias. 1287 71

Natural killer (NK) cell leukemia and lymphoma represent rare conditions with heterogeneity of biologic behavior, prognosis, and responsiveness to therapy. The initial diagnosis of NK-cell malignancies can be difficult because of the lack of immunophenotypic clonality markers, morphologic heterogeneity, and a poor correlation between cytomorphology and prognosis. Therapeutic recommendations for NK-cell malignancies are derived from retrospective studies or case reports. Immature NK-cell malignancies often have aggressive behavior with poor prognosis, despite administration of acute myeloid leukemia or acute lymphocytic leukemia induction chemotherapy. The use of high-dose chemotherapy with stem cell rescue resulted in a prolonged survival in a small series of patients. NK-cell malignancies originating from cells with mature phenotypes form a spectrum of diseases with distinct prognosis. Patients with aggressive NK-cell leukemia invariably die within several months. Nasal and nasal-like NK/T-cell lymphomas with limited stage disease often respond to radiation therapy alone or combination with chemotherapy and radiation therapy, with 5-year disease-free survival rates ranging from 30% to 75%. Patients with T-cell large granular lymphocyte leukemia or chronic NK-cell lymphoproliferative disease of granular lymphocytes can have an indolent clinical course with long survival without therapy. However, approximately 66% of patients with T-cell large granular lymphocyte leukemia require low-dose chemotherapy with methotrexate or cyclophosphamide or immunosuppressive therapy with glucocorticosteroids or cyclosporine A for symptomatic cytopenias during the course of their disease.
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PMID:Large granular lymphocyte leukemia and natural killer cell leukemia/lymphomas. 1294 9

Epstein-Barr virus (EBV)-associated T/NK-cell lymphoproliferative disorders (LPD) of children and young adults are sometimes termed as severe chronic active EBV infection (CAEBV), and are associated with an aggressive clinical course. However, these clinicopathological states and the role of EBV have not been clarified. A retrospective study was performed on 43 children and adult patients, who manifested EBV-associated T/NK-cell lymphoproliferative disorders (EBV-T/NK-LPD) and most of whom had experienced general illness with CAEBV for several months or years. Clinicopathologically, 43 patients were classified into four groups: group A (smoldering state) (n=7), morphological non-neoplastic LPD with chronic clinical course (several years); group B (chronic state) (n=10), non-neoplastic LPD with clonal EBV-infected cells and a chronic course; group C (leukemia/lymphoma state) (n=22), neoplastic LPD with a subacute course (years to months); group D (fulminant state) (n=4), neoplastic LPD with a fulminant course (weeks to days). The 43 patients comprised 21 males and 22 females. The median age of group A was 14 years, group B 12 years, group C 17 years, and group D 1 year. Four of 7 patients in group A, 3 of 10 in group B, 12 of 22 in group C, and all 4 in group D have died. Causes of death included hemophagocytic syndrome and/or tumor death. Genotypically and phenotypically, group C was composed of peripheral T-cell lymphoma (PTCL), and NK-cell leukemia/lymphoma (NKLL), and group D comprised cases of PTCL. Groups A and B exhibited increased NK- or T-cells (CD8>CD4), and rare B-cells. Serologic titers of EBV were only modestly elevated or not elevated in almost all cases. EBV early RNA-1 (EBER-1)-expressing EBV-infected cells were frequently encountered in each group, but the number of infected cells varied between the cases. The EBV genotype did not differ between the groups. Our findings support an important pathogenic role for EBV-infected T/NK-cell infection, rather than the EBV state, in CAEBV and consequent EBV-associated NK/T-neoplasia.
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PMID:Clinicopathological states of Epstein-Barr virus-associated T/NK-cell lymphoproliferative disorders (severe chronic active EBV infection) of children and young adults. 1506 38


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