Epstein-Barr virus-associated primary central nervous system lymphoma in a patient with adult T-cell leukemia / lymphoma

Diagnosis, prevention and treatment of central nervous system involvement in peripheral t-cell lymphomas

Non-Hodgkin lymphomas with T-cell immunophenotype encompass a heterogeneous group of infrequent neoplasms that follow variable clinical courses but prevalently include aggressive behavior and high mortality rates. The involvement of the central nervous system (CNS) is an uncommon event in T-cell lymphomas, with wide variability among the different disease entities. CNS can be affected either at initial diagnosis or at recurrence, and both forms are considered "secondary CNS T-cell lymphoma". Given the low incidence of secondary CNS T-cell lymphoma, related literature is sparse, contradictory, and primarily constituted by small case series and single case reports. However, reported studies uniformly suggest high mortality rates related to this event. Therefore, to improve our ability to identify high-risk patients and offer them successful CNS prophylaxis or timely and effective treatment once the event has occurred may prevent CNS-related T-cell lymphomas deaths. For example, some entities like aggressive adult T-cell leukemia/lymphoma, extranodal natural killer/T-cell lymphoma, and other peripheral T-cell lymphomas with involvement of two or more extranodal organs are prone to CNS dissemination and should be considered for personalized CNS prophylaxis. The level of evidence suggesting an increased risk of CNS recurrence for other T-cell lymphomas and for other risk factors is lower. Published case series show that, following the example of aggressive B-cell lymphomas, patients with T-cell lymphomas and putative increased CNS risk receive different forms of prophylaxis, mostly methotrexate and cytarabine delivered by intrathecal and/or intravenous routes, with varied success. To date, achievements in the treatment of CNS involvement in patients with aggressive B-cell lymphoma were not replicated in secondary CNS T-cell lymphomas, and identification of effective therapies remains an urgent research target. This review is focused on clinical findings, diagnosis, treatment, and prognosis of patients with T-cell lymphoma experiencing CNS dissemination either at presentation or relapse. It aims to provide logical and, oftentimes, evidence-based answers to the most common questions on the most probable risk factors to CNS involvement in patients with T-cell lymphoma, the indications and strategies to prevent this life-threating event, and the management of patients with CNS disease.

Epstein-Barr Virus Infection in the Development of Neurological Disorders

Epstein-Barr Virus (EBV) is a ubiquitous human herpesvirus that contributes to the etiology of diverse human cancers and auto-immune diseases. EBV establishes a relatively benign, long-term latent infection in over 90 percent of the adult population. Yet, it also increases risk for certain cancers and auto-immune disorders depending on complex viral, host, and environmental factors that are only partly understood. EBV latent infection is found predominantly in memory B-cells, but the natural infection cycle and pathological aberrations enable EBV to infect numerous other cell types, including oral, nasopharyngeal, and gastric epithelia, B-, T-, and NK-lymphoid cells, myocytes, adipocytes, astrocytes, and neurons. EBV infected cells, free virus, and gene products can also be found in the CNS. In addition to the direct effects of EBV on infected cells and tissue, the effect of chronic EBV infection on the immune system is also thought to contribute to pathogenesis, especially auto-immune disease. Here, we review properties of EBV infection that may shed light on its potential pathogenic role in neurological disorders.

Epstein-Barr virus-related diffuse large B-cell lymphoma in mogamulizumab-treated adult T-cell leukemia with incomplete T-cell reconstitution

Adult T-cell leukemia (ATL) is an aggressive mature T-cell malignancy with a poor prognosis. The anti-C-C motif chemokine receptor 4 (CCR4) antibody mogamulizumab (moga) reduces ATL cells and induces reconstitution of polyclonal T cells; however, ATL cases often remain resistant and moga sometimes causes fatal immunopathology. Epstein-Barr virus (EBV)-related B-cell lymphoma develops in severely immunocompromised subjects, and is particularly associated with impaired T-cell immunity. Here, we report an ATL patient who had received conventional chemotherapy plus moga, and subsequently developed EBV-related diffuse large B-cell lymphoma (DLBCL) of the central nervous system. Next-generation sequencing-based T-cell receptor repertoire analyses identified residual abnormal clones and revealed that reconstitution of polyclonal T cells was incomplete, even after moga treatment. Furthermore, a skin rash that developed after moga treatment was found to contain ATL clones. This case suggests that the limited therapeutic effects of moga and incomplete T-cell reconstitution are associated with severely impaired T-cell immunity and subsequent development of EBV-related DLBCL.

Adult T-cell lymphoma/leukemia presenting as isolated central nervous system T-cell lymphoma

Adult T-cell leukemia/lymphoma (ATLL) is a T-cell neoplasm, associated with infection by the retrovirus human T-lymphotropic virus type 1 (HTLV-1). Central nervous system (CNS) involved by ATLL is often occurred in advanced disease, such as acute and lymphomatous variants. On the other hand, isolated CNS lymphoma is rare. We repot a 50-year-old woman who presented with multiple infiltrative brain lesions on the magnetic resonance (MR) imaging. Results of initial biopsy of brain tumor indicated CNS vasculitis. The patient received one course of high-dose methotrexate and MR imaging of brain revealed remission of infiltrative lesions. Two years later, new brain lesions were detected. Histopathologic examination of specimens via craniotomy revealed T-cell lymphoma. The patient responded poorly to subsequent chemotherapy, and salvage whole-brain irradiation was performed. Six months later, the patient had hepatosplenomegaly, hypercalcemia, and multiple lymphocytes with a cloverleaf appearance in circulation. Results of flow cytometry analysis of peripheral blood indicated ATLL and antibodies to human T-lymphotropic virus type 1 (HTLV-1) were detected. Clinicians should screen HTLV-1 infection when patients are diagnosed with peripheral T-cell lymphoma. Combined antiviral therapy and intensive chemotherapy may improve the outcomes of ATLL.

Primary central nervous system lymphoma in Miyazaki, southwestern Japan, a human T-lymphotropic virus Type-1 (HTLV-1)-endemic area: clinicopathological review of 31 cases

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive brain tumor. The aim of this study was to clarify the prevalence of T-cell-type PCNSL (T-PCNSL) in a human T-lymphotropic virus type-1 (HTLV-1)-endemic area of Southwestern Japan. We retrospectively investigated 31 PCNSL cases diagnosed between 1996 and 2013 at the University of Miyazaki Hospital. These cases accounted for 4.4% of all nodal or extranodal malignant lymphomas. Histologically, most of these cases were diagnosed as diffuse large B-cell lymphoma, while only two cases were considered to be low-grade and high-grade B-cell lymphoma (not otherwise specified). No T-PCNSL was found in this series. In addition, Epstein-Barr virus-encoded RNAs were not detected by in situ hybridization in any of the cases. Overall, no T-PCNSL cases were found in 18 years in a region with a high frequency of HTLV-1 seropositivity, namely, Southwestern Japan. This suggests that PCNSL and lymphomas of other anatomical sites are biologically distinct.

Extended lifespan of normal human B lymphocytes experimentally infected by SV40 or transfected by SV40 large T antigen expression vector

SV40 footprints were detected in different lymphoproliferative disorders and in blood specimens of healthy donors. However, little is known on the ability of SV40 to infect/transform normal human B-lymphocytes. In this in vitro study, experimental SV40 infection and SV40 Tag transfection of normal human B-lymphocytes from healthy blood donors were carried out. In SV40 infected/transfected purified B-cells, during the time course analyses, viral DNA sequences were detected by PCR, while Tag mRNA and protein were revealed by RT-PCR and immunocytochemistry, respectively. Trypan blue and Alamar blue assays showed an increase in number of cells and cell viability of infected/transfected B-cells up to day 50, then a drastic and constant cell number reduction was observed in cultures. Approximately 50% of both infected and transfected B-cells appeared morphologically transformed. SV40 viral progeny and its titer from infected B-cells was determined by plaque assay in permissive CV-1 cells. Our data indicate that human B-cells can be efficiently infected by SV40, release a viral progeny, while at the same time are transformed. SV40 infected/Tag transfected B-cells may represent an experimental model of study for investigating new biomarkers and targets for innovative therapeutic approaches in human B-cell malignancies.

Diffuse large B-cell lymphoma in human T-lymphotropic virus type 1 carriers

We describe the clinical and pathological characteristics of seven patients who were human T-lymphotropic virus type 1 (HTLV-1) carriers and had a pathological diagnosis of de novo diffuse large B-cell lymphoma. Interestingly, three of our cases showed positive expression of Epstein-Barr-virus, (EBV-) encoded RNA within the tumor cells indicating a possible interaction between these two viruses. Furthermore, our three EBV-positive cases presented with similar clinical characteristics such as early clinical stage and low-risk indices. To the best of our knowledge, this is the first case series describing the characteristics of HTLV-1-positive DLBCL patients. The potential relationship between HTLV-1 and EBV should be further explored.