Extranodal T-cell lymphoma mimicking malignant histiocytosis

Hepatosplenic T cell lymphoma. A review on 45 cases since the first report describing the disease as a distinct lymphoma entity in 1990

Peripheral T cell lymphomas are a heterogeneous group of post-thymic, mature lymphoid malignancies, accounting for approximately 10-15% of all non-Hodgkin's lymphomas. A rare entity within this group is represented by hepatosplenic gammadelta T cell lymphoma, which is characterized by primary extranodal disease with typical sinusoidal or sinusal infiltration of the liver and the spleen, respectively, by expression of the T cell receptor gammadelta chain, and by a number of other frequent clinicopathological features including aggressive course of disease. In contrast to these common attributes some biologic characteristics such as expression of cytotoxic proteins and cytotoxic activity have been controversial. In this review, clinicopathological, immunophenotypical, molecular biological, cytogenetical and biological findings, and diagnostic and therapeutic difficulties in hepatosplenic gammadelta T cell lymphoma are discussed.

Hepato-splenic gammadelta T-cell lymphoma: a rare entity mimicking the hemophagocytic syndrome

Hepatosplenic gammadelta T-cell lymphoma is a rare histologic type of the peripheral T-cell lymphomas, clinically characterized by predominant involvement of liver and spleen, no or little adenopathy, and an often aggressive course; it affects mainly adolescents and young adults, with a male predominance. Postthymic T-cell malignancies are heterogeneous in their clinical and laboratory features. Among the gammadelta postthymic T-cell lymphomas, two distinct entities (cutaneous and hepatosplenic, respectively) are reported in the literature. The former shows predominant multiple involvement of the skin and subcutaneous tissue; it occurs mostly in older patients and the phenotype is CD3-, CD4-, CD8-. Because of the small number of reports, the course of the disease was unknown. The latter shows a clinical picture characterized by hepatosplenomegaly, no or little adenopathy, and sometimes systemic symptoms (fever, cytopenias likely due to hypersplenism); it presents a peculiar sinusoidal involvement of liver and spleen. The bone marrow histologic feature often reveals a little infiltration, especially sinusoidal and easily underestimated phenotype: CD2+, CD3+, CD7+, CD5-, CD4-, CD8-, CD44+. Few cases of this lymphoma associated by hemophagocytic syndrome are described (Sun, 1990; Kadin, 1981; Jaffe, 1983). We report a case of a young man with a rapid and fatal course in which the more important clinical feature was hemophagocytosis. The diagnosis of lymphoma was very difficult because of paucity of histologic involvement, and only the rearrangement of TCR gamma chain gene by polymerase chain reaction on paraffin sections confirmed a clonal T-cell proliferation.

Molecular evidence of bone marrow involvement in advanced case ot Tgammadelta lymphoma with secondary myelofibrosis

We describe the case of a middle-aged man with long indolent course of generalized Tgammadelta lymphoma. The onset of secondary myelofibrosis made cytological monitoring of the bone marrow infiltrates impossible. As during progression of the disease splenectomy revealed typical histological features of a high-grade hepatosplenic Tgammadelta lymphoma, the low-grade bone infiltrate was considered a secondary lymphoma. The use of the polymerase chain reaction helped to detect a constant and identical monoclonal rearrangement pattern of the T-cell receptor gamma-chain gene in both bone marrow and splenic T-cell infiltrates. The notion of a secondary spread of malignant T-cells to the bone marrow was thereby confirmed despite striking cytological differences between bone marrow and splenic infiltrates. This is the first report of a diagnostic DNA-based molecular approach using fixed decalcified bone marrow. This method may provide a major tool when dealing with myelofibrosis, which normally hampers sampling of cytological specimens.

T gamma/delta hepatosplenic lymphoma in a heart transplant patient after an Epstein-Barr virus positive lymphoproliferative disorder: a case report

BACKGROUND

An unusual case of a peripheral T-cell lymphoma of T gamma/delta hepatosplenic type (Tgamma/deltaHSL) that arose in a child 5 years after she received a heart transplant and 9 months after she developed Epstein-Barr virus (EBV) positive, B-cell lymphoid hyperplasia involving the tonsils is presented. The majority of the reported cases of Tgamma/deltaHSL have been described in young adult men without antecedent immunodeficiency; several well documented cases of Tgamma/deltaHSL in the posttransplant setting have been described previously, but none has been described in a child (or an adult) with a previously diagnosed EBV+ B-cell lymphoid hyperplasia.

METHODS

Standard histologic, immunohistochemical, flow cytometric, and molecular genetic techniques were used in the evaluation of diagnostic material.

RESULTS

The patient's Tgamma/deltaHSL involved the spleen in a predominantly cordal pattern, and infiltrated the liver in an exclusively sinusoidal distribution. Bone marrow involvement was focal and interstitial. In all locations, malignant cells were of intermediate or large size and had oval nuclei with coarse chromatin, with a scant or moderate amount of eosinophilic cytoplasm. This Tgamma/deltaHSL expressed the characteristic CD2+, CD3+, [CD4- CD8-], Tdelta1+ phenotype, and malignant cells also expressed the natural killer cell marker CD56. Cytogenetic studies demonstrated isochromosome 7q with the addition of trisomy 8 as the tumor progressed. Southern blot analysis demonstrated clonal rearrangements of the gamma, delta, and beta loci of the T-cell receptor but did not identify EBV DNA within the tumor cells.

CONCLUSIONS

This case highlights the fact that a full range of lymphoid proliferations is possible in the posttransplantation period, and that a prior diagnosis of a B-cell disorder does not preclude the development of a subsequent T-cell posttransplant lymphoproliferative disorder (PTLD), which should be formally evaluated, especially if clinical circumstances appear atypical for a PTLD of the "usual" (EBV-related, B-cell) type.

Large cell lymphoma with initial presentation in the bone marrow

This report describes 14 cases of large cell lymphoma with initial presentation as marrow involvement in the absence of peripheral lymphadenopathy. The disease affected mainly the middle-aged and elderly, with male predominance. Most patients presented with swinging fever and peripheral blood cytopenia. Reactive hemophagocytic syndrome was a common finding, causing significant morbidity and mortality. Peripheral lymphadenopathy was absent (by case selection), but involvement of the liver, spleen and paraaortic lymph nodes could be demonstrated in some cases. However, in some patients, the involvement was apparently restricted to the bone marrow. Involvement of the bone marrow was often subtle, and could be missed on causal examination. Immunohistochemical studies on eight cases showed that four exhibited a B-cell phenotype, three a T-cell phenotype and one a non-T non-B phenotype. The prognosis was poor, with survival being measured in days to weeks in most patients.

A study of lymphoma of large granular lymphocytes with modern modalities: report of two cases and review of the literature

Two cases of lymphoma of large granular lymphocytes are reported. The first case expressed natural killer (NK) cell, some T-cell (CD 2, CD 5, CD 8), and HLA-DR antigens, but was negative for other T-cell (CD 3, CD 4, CD 7), T-cell receptor (TCR), B-cell, and myeloid antigens. Germline configuration was demonstrated for TCR, and immunoglobulin heavy and light chain genes. The second case expressed NK cell, some T-cell (CD 3, CD 7, CD 8), and TCR antigens, but was negative for other T-cell (CD 4, CD 5), B-cell, myeloid, and HLA-DR antigens. Rearrangement of TCR alpha and beta chains were detected. Thus, the findings of case 1 were consistent with true NK cell lineage and case 2 with NK-like T-cell lineage. Our report underscores the heterogeneity of this newly recognized lymphoma, which nevertheless carries a consistently poor prognosis and is probably more prevalent in the Asian population. This study also provides information concerning immunophenotypes of cellular infiltrates in internal organs and cytogenetic abnormalities in this lymphoma; neither has been reported frequently in the literature. The importance of detecting cytoplasmic granules in tissue imprints or electron micrographs for differentiating other T-cell lymphomas is emphasized, and the classification of large granular lymphoproliferative disorders is discussed.