Epstein-Barr virus-associated multicentric leiomyosarcoma in an adult patient after heart transplantation: case report and review of the literature

Successful Management of Recurrent Epstein-Barr Virus-Associated Multilocular Leiomyosarcoma After Cardiac Transplantation

BACKGROUND

In contrast to Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disorders (PTLD), EBV-associated leiomyomatous tumors have thus far only rarely been described.

CASE REPORT

Two years after heart transplantation with ATG induction, cyclosporine (CsA; trough levels of 250 ng/mL)-based triple drug immunosuppression), a 23-year-old patient developed a small round lesion within the left lateral liver segment. The patient underwent ultrasound-guided biopsy followed by liver resection. Histological and immunohistological examination showed a leiomyosarcoma. In situ hybridization using EBV-specific EB endoplasmic reticulum-RNA showed an intensive signal in almost all tumor cells. The tumor stained for EB nuclear antigen (EBNA)-2-protein. Immunosuppression was drastically reduced, namely, CsA levels <100 ng/dL, prednisolone 5 mg, azathioprine withdrawn, and antiviral chemotherapy initiated with 10 days of IV gancyclovir and acyclovir followed by oral famcyclovir. During the follow-up, anti-EBV-IgM, anti-early antigen antibodies, and anti-EBNA antibodies were continuously monitored excluding significant EBV replication. Eighteen months post-liver resection, and high-resolution computed tomography scan demonstrated two paravertebral tumors. These lesions and a small nodule at the left ankle were resected revealing identical leiomyosarcomata. Immunosuppression was further reduced (CsA levels 75 ng/dL) and famcyclovir maintenance therapy started. Nevertheless, 2 years later the patient again developed tumor recurrence (perirectal, liver, and right adrenal gland); the tumors were surgically removed. The therapy was switched to Rapamycin and famcyclovir was continued. Three years after the last surgical intervention, the patient is well and recurrence-free.

CONCLUSION

Long-term survival in patients with posttransplant EBV-associated leiomyosarcoma can be achieved by combined surgical intervention, reduction of immunosuppression, switch to Sirolimus, and antiviral chemotherapy.

Viral interactions with the Notch pathway

The Notch signaling pathway influences cell fate decisions, proliferation versus differentiation and cell survival. Viruses both utilize and manipulate the differentiation state of infected cells, promote or block cell cycling and employ a variety of mechanisms to evade innate cellular anti-viral responses and promote cell survival. In light of these commonalities, it is perhaps not surprising that several viruses have tapped into the Notch pathway to advance their own life cycles. This first became apparent from studies showing targeting of Epstein-Barr virus proteins to the nuclear effector of Notch signaling CSL (CBF1/RBPJk). More recently the Kaposi's sarcoma-associated herpesvirus RTA protein has been found to bind CSL. Notch pathway interactions have also been described for adenovirus SV40 and human papilloma virus. This review focuses on the herpesvirus protein interactions with the Notch pathway and the insights that these interactions have provided.

Brain involvement in multicentric Epstein-Barr virus-associated smooth muscle tumours in a child after kidney transplantation

Epstein-Barr virus (EBV)-associated smooth muscle tumours (SMT) have been reported in young patients with induced immunosuppression associated with organ transplantation, acquired immunodeficiency syndrome or congenital immunodeficiencies. EBV-associated SMT are frequently multicentric or multifocal and often occur in unusual locations. We are reporting a case of EBV-associated multicentric SMT that occurred after kidney transplantation in a 2-year-old boy with a history of oligomeganephrony. Headaches and left VIth cranial nerve paralysis led to the discovery of a brain tumour 3 years after transplantation. There were multiple pulmonary, hepatic and splenic nodules and enlarged mesenteric lymph nodes. Histological examination revealed multicentric SMT of uncertain malignant potential. Further investigations using in situ hybridisation demonstrated EBV early RNAs in the nucleus of most tumour cells. The immunosuppressive therapy was reduced, and the child was treated with chemotherapy, but died 2 months later, due to neurological complications.

Inhibition of Epstein-Barr virus-induced growth proliferation by a nuclear antigen EBNA2-TAT peptide

Epstein-Barr virus (EBV) causes infectious mononucleosis and is associated with cancers in immunocompromised populations. Antiviral drugs targeted against lytic viral replication have limited efficacy in these disease settings. EBV infection of peripheral blood mononuclear cells induces growth proliferation and the EBV latency Epstein-Barr virus-encoded nuclear antigen (EBNA)2 transcriptional transactivator (TAT) is essential for this response. EBNA2 targets the cellular DNA-binding protein CBF1 to mimic activated Notch signaling. A 10-aa peptide from the CBF1 interaction domain of EBNA2 was synthesized as a fusion with the protein transduction domain of HIV-1 TAT. The EBNA2-TAT peptide blocked EBNA2-CBF1 interaction in an in vitro GST affinity assay and labeling with fluorescein confirmed that the EBNA2-TAT peptide efficiently entered cultured B cells. Neither EBNA2-TAT, nor a mutant peptide with a 2-aa substitution that was unable to block the EBNA2-CBF1 interaction, significantly affected the growth of non-EBNA2-expressing EBV(-) B cells or Burkitt's lymphoma Akata cells. However, treatment of an EBV-immortalized lymphoblastoid cell line with the EBNA2-TAT peptide stopped cell growth and reduced cell viability. RT-PCR analyses of gene expression in the peptide-treated lymphoblastoid cell line cultures revealed that EBNA2-TAT treatment down-regulated the EBNA2-responsive viral LMP1 and LMP2 genes and cellular CD23, intercellular adhesion molecule 1, BATF, and Cdk1 genes while up-regulating expression of the cyclin-dependent kinase inhibitor p21. EBV-induced outgrowth of B cells from cultured peripheral blood mononuclear cells was also blocked in a dose-responsive manner by the EBNA2-TAT peptide. This study suggests that cell-permeable EBNA2 peptides may have potential as novel anti-EBV therapeutics.

[Epstein-Barr virus associated central nervous system leiomyosarcoma occurring after renal transplantation: case report and review of the literature]

Central nervous system leiomyosarcomas are extremely rare, however, they became more frequent among immunodeficient patients, either in a patients infected with human immunodeficiency virus (HIV), or after organ transplantation. The data of the literature indicate that the infection by Epstein-Barr virus (EBV) plays a causal role in the development of these tumours but its precise role in the oncogenesis remains unresolved. We report a new case of EBV associated leiomyosarcoma of the left cavernous sinus occurring after renal transplantation. The epidemiological, clinical, pathological and therapeutic characteristics of these tumours are discussed.

Complex genomic rearrangement of ALK loci associated with integrated human Epstein-Barr virus in a post-transplant myogenic liver tumor

Epstein-Barr virus (EBV) is a ubiquitous viral agent, well known to be associated with lymphoid, epithelial, and smooth-muscle malignancies in immunocompromised individuals. This report describes a 10-year-old patient with an EBV-related liver tumor occurring after kidney transplantation. The neoplasm presented a phenotypic spectrum, ranging from a smooth-muscle tumor to an inflammatory pseudotumor (IPT). The neoplastic cells failed to disclose CD21, CD35, or ALK expression, the latter confirmed by reverse-transcription polymerase chain reaction. Cytogenetic analysis revealed a single clonal cell population showing 46,XY,del (2)(p23),der(3)t (2;3)(p23;q29),der(21) t(Y;21)(q12;p13) karyotype. By metaphase FISH analysis, the neoplastic cells demonstrated the presence of two molecularly different but related aberrant clones, one with the loss of one ALK allele and the second with translocation of the 3'end of ALK kinase domain on the der(3) chromosome. Using FISH with an EBV-specific and 3'end ALK DNA probes, a co-localization of the viral DNA and the ALK sequences was found on the der(3) chromosome. Metaphases with loss of rearranged ALK did not show integrated virus; instead, viral particles together with an associated 3'end ALK domain formed an ex-chromosomal, episomal-like type configuration. The interphase study, using dual-color 5'/3' end ALK FISH assay, revealed 30% of nuclei with only one fused signal, confirming the total loss of one ALK allele in the subset of tumor cells. A combined immunofluorescence and FISH study indicated this separate clonal variant to correspond to desmin-positive smooth-muscle cells. In contrast, desmin-negative myofibroblasts showed the presence of both normal and rearranged ALK alleles. Our results indicate that ALK locus may be a target of EBV integration, a hitherto unreported finding. Although the sustained clonal expansion in EBV-related smooth-muscle tumors/IPTs may depend on functions provided by the EBV oncogenic proteins, the tumor phenotype may be further modified by the secondary genomic rearrangements imposed by the virus during and/or after the integration event. In this respect, the observed phenotypic heterogeneity most likely reflects divergence during neoplastic progression, with the subsequent expansion of morphologically and molecularly distinct but cytogenetically related clones.

Epstein-Barr virus-associated leiomyomatosis and posttransplant lymphoproliferative disorder in a child with severe combined immunodeficiency: case report and review of the literature

The occurrence of smooth muscle neoplasms and lymphoproliferative disorders in immunocompromised patients is well recognized. We report the case of an 8-year-old girl with adenosine deaminase (ADA)-deficient severe combined immunodeficiency (SCID) status post-bone marrow transplant (BMT), in whom Epstein-Barr virus (EBV) was detected in innumerable leiomyomas involving the gallbladder (leiomyomatosis), and multifocal leiomyomas in liver, spleen, pancreas, intestinal tract, and lung. The leiomyomas of the gallbladder, liver, spleen, and lung were asymptomatic, while those located in the colon became clinically manifest by recurrent lower intestinal hemorrhage. The patient also developed extensive EBV-associated polymorphic lymphoproliferative disorder (PTLD) in nodal and extranodal sites. In addition, there were pulmonary and gastric adenovirus and small and large intestine cryptosporidum infections. Our case appears to be the first example of leiomyomatosis of the gallbladder coexisting with multifocal leiomyomas of the liver, spleen, pancreas, intestinal tract, and lung, as well as EBV-derived lymphoproliferative disorder in a young girl with ADA-deficient SCID. Awareness of the pattern of involvement and of the coexistence of benign leiomyomatous proliferations with lymphoproliferative disorder is of value when gallbladder, pancreatic, biliary tree, lung, and intestinal lesions become clinically manifest in these patients. The demonstration of EBV infection in both leiomyomata and the PTLD suggests a common pathogenesis that may have therapeutic and prognostic implications.

Biological aspects of Epstein-Barr virus (EBV)-infected lymphocytes in chronic active EBV infection and associated malignancies

Most primary Epstein-Barr virus (EBV) infections are clinically inapparent, but occasionally EBV infection can cause acute infectious mononucleosis. EBV has been linked to a variety of hematologic and non-hematologic malignancies. Chronic active EBV (CAEBV) infection designates a recently identified EBV-associated syndrome characterized by a variety of serious hematological disorders, including malignant lymphoma. EBV was found to infect circulating T- and/or NK-cells in patients with CAEBV infection. These EBV-infected T- and/or NK-cells express EBNA-1, LMP-1, and LMP-2A, a type II form of EBV latency, which is also observed in nasopharyngeal carcinoma (NPC), Hodgkin's disease (HD), and peripheral T-cell lymphoma. CAEBV infections may thus represent a subset of EBV-associated T- and/or NK-cell lymphoproliferative disorders.

Smooth muscle tumors of soft tissue

This paper presents an overview of smooth muscle tumors occurring in deep soft tissue. Although the existence of leiomyomas of soft tissue has been questioned in the past, it appears that they do exist but are rare, and must be diagnosed using stringent histologic criteria that include no atypia and minimal or no mitotic activity. They segregate into two distinct clinicopathologic groups, one group occurring in patients of either sex in deep somatic soft tissue and the second occurring primarily in women in the pelvic retroperitoneum. The latter bear a histologic similarity to uterine leiomyomas. Leiomyosarcomas occur in retroperitoneum followed by deep somatic soft tissue and are diagnosed by the presence of nuclear atypia and essentially any level of mitotic activity. Leiomyosarcomas of deep somatic tissue commonly arise from small veins and their behavior can be predicted by a number of factors including age, grade, and "disruption" of tumor. Conversely, few factors have proved to be prognostically useful for leiomyosarcomas of the retroperitoneum, as nearly all prove fatal. Epstein Barr virus (EBV)-associated smooth muscle tumors are a recently emerging entity that occur in the setting of immunocompromise. Their behavior is closely tied to the immune status of the patient rather than to specific histologic features.

Epstein-Barr virus-associated smooth muscle tumour: a distinctive mesenchymal tumour of immunocompromised individuals

immunosuppressed patients are predisposed to the development of smooth muscle tumours which show near consistent association with Epstein-Barr virus (EBV). This report describes a 37-year-old patient with acquired immunodeficiency syndrome who initially presented with two masses in the liver. Image-guided core biopsy revealed a spindle cell tumour with histological and immunological features of smooth muscle neoplasm which was shown by in situ hybridisation for EBV early RNAs to be EBV-associated. The literature on this uncommon entity is critically reviewed and the differential diagnosis is also discussed.