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

EBV-Associated Smooth Muscle Tumor in the Malar Area of an HIV-Positive Patient: A Case Report

BACKGROUND

EBV-associated smooth muscle tumors (EBV-SMTs) are rare and typically develop in individuals with a compromised immune system, particularly those who have acquired immunodeficiency syndrome (AIDS) or who have undergone organ transplants.

METHODS

We document a case of EBV-SMT in an HIV-positive 25-year-old man. The lesion was incised and assessed histologically and a panel of immune markers were performed. EBV association was demonstrated by in situ hybridization for EBV-encoded RNA (EBER-ISH).

RESULTS

Microscopically, the tumor composed of mildly pleomorphic, ovoid to spindled cells with numerous slit-like vascular channels. The tumor cells exhibited diffuse and strong immunoreactivity for smooth muscle actin (SMA) and focal positivity for h-caldesmon. EBER-ISH of the tumor cells revealed strong positive nuclear signals.

CONCLUSION

The histopathological features of EBV-SMT do not conform to either benign or malignant SMTs and it has a peculiar predilection to develop at sites unusual for leiomyoma or leiomyosarcoma. The key diagnostic features of EBV-SMT include history of immunosuppression, histologic evidence of primitive and mildly pleomorphic cells maintaining blunt nuclear features in most areas, and positivity for EBER-ISH.

CARMIL2 Immunodeficiency with Epstein Barr Virus Associated Smooth Muscle Tumor (EBV-SMT). Report of a Case with Comprehensive Review of Literature

Background: Primary immunodeficiency (PID) having defects related to lymphocyte cytotoxic pathway or T-cell dysfunction are well known for developing opportunistic infections and Epstein-Barr virus (EBV)-associated diseases. CARMIL2 deficiency is a recently described combined immunodeficiency (CID) disorder characterized by defective CD28-mediated T cell co-stimulation, altered cytoskeletal dynamics, susceptibility to various infections and Epstein Barr Virus smooth muscle tumor (EBV-SMT). Case report: We report a homozygous CARMIL2 pathogenic variant presenting with recurrent infections and EBV associated smooth muscle tumor (SMT) in a child. Conclusion: The present study reports that EBV SMT may occur in a child with CARMIL2 deficiency.

Cutaneous Epstein-Barr virus-associated smooth muscle tumor in immunosuppression

A 36-year-old renal transplant recipient presented 15 months post-transplantation with a cutaneous spindle cell neoplasm with features of smooth muscle differentiation treated with local excision. 1.4 years later, a magnetic resonance imaging liver scan with gadolinium demonstrated multiple bilobar enhancing hepatic lesions, in keeping with metastases. A core biopsy revealed morphological appearances similar to the previous cutaneous spindle cell neoplasm. Epstein-Barr virus early RNA (EBER) in situ hybridization demonstrated strong diffuse staining of both cutaneous and liver tumor cells for EBER indicative of Epstein-Barr virus (EBV) infection. This is a rare presentation of multifocal EBV-associated smooth muscle tumors first presenting in the skin in an adult renal transplant recipient, which, despite being multifocal and involving the liver, may confer a better prognosis than predicted.

Treatment response with sirolimus for a pediatric patient with an EBV-associated smooth-muscle tumor after bone marrow transplantation

Epstein-Barr virus-associated smooth-muscle tumors (EBV-SMTs) are unique and rare neoplasms described in immunocompromised patients. The case describes a nine-year-old female with a history of acute lymphoblastic leukemia with relapse and subsequent allogeneic bone marrow transplantation who presented with multiple EBV-SMTs of the liver. EBV utilizes the mammalian target of rapamycin (mTOR) pathway for tumor growth, and sirolimus, a mTOR inhibitor, has shown to result in a short-term response. We now report an extended treatment response with sirolimus in a pediatric patient with an EBV-SMT.

Epstein-Barr virus (EBV) status in colorectal cancer: a mini review

Epstein-Barr virus (EBV) is a well-characterized oncovirus, associated with several malignancies. The complex and heterogeneous nature of colorectal cancer (CRC) has led to many epidemiological causal associations with CRC. However, a direct causal link between microbial infections and CRC has not been established yet. Our review indicates that the current evidence for the presence and role in EBV in CRC is insufficient and contradictory. The design of the analyzed studies, sample size as well as methodology used for EBV detection varied markedly and consequently may not lead to meaningful conclusions. The presence of EBV in other colorectal tumors (lymphomas, smooth muscle tumors) is in line with their status at other anatomic locations and may have therapeutic implications with EBV-specific vaccines. On the other hand, studies exploring EBV in colorectal adenoma-carcinoma sequence and its molecular genetic characteristics are largely missing and may significantly contribute to a better understanding of the role of EBV in CRC.

Resolution of Multifocal Epstein-Barr Virus-Related Smooth Muscle Tumor in a Patient with GATA2 Deficiency Following Hematopoietic Stem Cell Transplantation

We performed allogeneic hematopoietic stem cell transplantation in a patient with GATA2 deficiency and an Epstein-Barr virus (EBV)-related spindle cell tumor involving the liver and possibly bone. He received a matched-related donor transplant with donor peripheral blood stem cells following a myeloablative conditioning regimen. He achieved rapid and high levels of donor engraftment and had complete reversal of the clinical and immunologic phenotype of MonoMAC/GATA2 deficiency and eradication of the EBV tumors after 3 years of follow-up. Thus, allogeneic hematopoietic stem cell transplant results in reconstitution of immunologic function and cure of EBV-associated malignancy in MonoMAC/GATA2 deficiency.

Primary leiomyoma of the liver: a review of a rare tumour

Context. Primary leiomyoma of the liver is a rare tumour with uncertain pathogenesis with similar presentation with other tumours of the liver. Little is known about its clinical course. Objectives. To review the literature for case reports of primary leiomyoma of the liver. Methods. Extensive literature search was carried out for case reports of primary leiomyoma of the liver. Results. A total of 36 cases of primary leiomyoma of the liver were reviewed. The mean age of presentation is 43 years with slight female sex affectation; females accounted for 55.6% of the cases reported in the literature. The average size of the tumour is 8.7 cm. 34.4% of the cases reviewed were incidental finding with the mean follow-up time of 33 months with most cases reporting no evidence of disease. Conclusions. Primary leiomyoma of the liver is very rare tumour with complex pathogenesis which remains largely unknown. Imaging of the tumour does not allow for a tissue specific diagnosis; hence histological review of the tissue specimen and immunohistochemical stains are imperative for diagnosis. Surgical resection is both diagnostic and curative. The diagnosis of primary leiomyoma of the liver should be considered as a differential in the management of liver tumours.

A de novo unclassified malignant spindle cell neoplasm of liver allograft

Spindle cell neoplasms are rarely reported in liver allografts; most are benign and associated with Epstein-Barr virus infection. We present a case of a malignant spindle cell neoplasm arising in a liver allograft. The patient underwent orthotopic liver transplant for cirrhosis secondary to nonalcoholic steatohepatitis. After 2 years, he presented with vague abdominal complaints. Imaging studies revealed a 10-cm right hepatic lobe mass. The patient underwent right-sided hepatectomy. The tumor displayed areas of broad, relatively hypocellular fascicles, whorls, and perivascular clustering; spindle cells with mild to moderate nuclear pleomorphism; and relatively abundant eosinophilic cytoplasm. Mitotic activity ranged from 2 to 4 mitotic figures per 20 high-power fields. Immunostaining displayed positivity for epithelial membrane antigen, vimentin, CD99, BCL2, cytokeratin, and human herpesvirus 8. Interphase fluorescence in situ hybridization findings were negative for a translocation involving the SS18 gene (18q11). We believe the tumor represents the first reported case of a novel unclassified spindle cell malignant neoplasm in a liver allograft.

Epstein-Barr virus negative primary hepatic leiomyoma: Case report and literature review

Primary hepatic leiomyoma is a neoplasm of mesenchymal origin and occurs only rarely. Secondary to benign smooth muscle proliferation, it is usually found in adult women and is associated with Epstein-Barr virus (EBV) infection. Here, we report the 29^th case of primary hepatic leiomyoma with its unique features related to diagnosis, treatment and developmental biology. A 48-year-old man, with an immunocompromised status, complained of pain in the upper quadrant of the abdomen. Serological analysis indicated no presence of hepatitis virus, no human immunodeficiency virus, and no EBV infection. The levels of α-fetoprotein and carcinoembryonic antigen were normal. A mass was detected in segment III of the hepatic lobe by ultrasonography and an abdominal computed tomography scan. Endoscopy had negative findings. Exploratory laparotomy found no existing extrahepatic tumor and left lateral lobectomy was performed. Pathological examination showed the mass to be a typical leiomyoma. The cells were positive for α-smooth muscle actin and desmin, and negative for the makers of gastrointestinal stromal tumor (GIST), including CD117, CD34 and DOG1 (discovered on GIST1). In situ hybridization revealed negative status for EBV-encoded small RNA. After left lateral lobectomy, the patient was not given chemotherapy or radiotherapy. During a 2-year follow-up, no sign of local recurrence or distant metastasis was observed. In conclusion, we report a rare case of primary hepatic leiomyoma in a male patient without EBV infection. Hepatic resection was curative. This case presents data to expand our knowledge concerning the complex and heterogeneous nature of primary liver leiomyoma, indicating that EBV infection is important but neither necessary nor sufficient for the development of primary liver leiomyoma.

Extracellular circulating viral microRNAs: current knowledge and perspectives

MicroRNAs (miRNAs) are small non-coding RNAs responsible of post-transcriptional regulation of gene expression through interaction with messenger RNAs (mRNAs). They are involved in important biological processes and are often dysregulated in a variety of diseases, including cancer and infections. Viruses also encode their own sets of miRNAs, which they use to control the expression of either the host’s genes and/or their own. In the past few years evidence of the presence of cellular miRNAs in extracellular human body fluids such as serum, plasma, saliva, and urine has accumulated. They have been found either cofractionate with the Argonaute2 protein or in membrane-bound vesicles such as exosomes. Although little is known about the role of circulating miRNAs, it has been demonstrated that miRNAs secreted by virus-infected cells are transferred to and act in uninfected recipient cells. In this work we summarize the current knowledge on viral circulating miRNAs and provide a few examples of computational prediction of their function.

Bilateral adrenal EBV-associated smooth muscle tumors in a child with a natural killer cell deficiency

EBV-associated smooth muscle tumors are found in immunocompromised patients, most commonly HIV/AIDS. We present a 12-year-old girl with the first documented case of EBV-related smooth muscle tumors in the presence of a rare classic NK cell deficiency. This sheds light on the role of NK cells in controlling EBV-related smooth muscle tumors.

Human Immunodeficiency Virus–Related Gastrointestinal Pathology: A Southern Africa Perspective With Review of the Literature (Part 2: Neoplasms and Noninfectious Disorders)

Context.—Human immunodeficiency virus (HIV) infection is rife in sub-Saharan Africa and in southern Africa in particular. Despite the increasing availability of antiretroviral therapy in this region, HIV-associated neoplasms remain common and frequently involve the gastrointestinal tract, which may also demonstrate other noninfectious, HIV-related pathology.

Objective.—To review the histopathologic findings and distinguishing features of neoplastic and noninfectious, HIV-associated gastrointestinal disorders in southern Africa and relate those findings to the documented international literature.

Data Sources.—The available literature on this topic was reviewed and supplemented with personal experience in a private histopathology practice in South Africa.

Conclusions.—In southern Africa, a diverse range of HIV-related neoplasms and noninfectious gastrointestinal disorders is seen, but published data for the region are scarce. The gastrointestinal disorders include drug-associated pathology, gastrointestinal manifestations of the immune reconstitution inflammatory syndrome, idiopathic chronic esophageal ulceration, and the controversial entity of HIV enteropathy.

Dermal Epstein Barr virus--associated leiomyosarcoma: tocsin of acquired immunodeficiency syndrome in two children

Although rare in childhood, a relatively high incidence of smooth muscle tumors are recognized in patients with AIDS, mainly in association with Epstein Barr virus (EBV) infection. Although EBV-associated smooth muscle tumors have been documented rarely in the subcutis of AIDS patients, dermal involvement has not been described to date. This report describes dermal EBV-associated leiomyosarcomas (EBV-LMS) with a nodular but superficial plaque-like appearance on the lower limbs of 2 males, 9 and 12 years old. Histopathological assessment of the excised lesions demonstrated hypercellular mitotically active dermal tumors with hyperchromatic spindle and round cells, arranged in short fascicles and sheets, with microfoci of necrosis. A smooth muscle immunophenotype, including prominent desmin immunopositivity, and positive EBV-encoded RNA in situ hybridization investigation confirmed a diagnosis of EBV-LMS. Subsequent HIV seropositivity and AIDS were confirmed in both patients. Both patients also had pulmonary tuberculosis and received antituberculous therapy. Patient 1 had a 3 cm re-excision of the prior tumor site. He received highly active antiretroviral therapy, completed 6 months of antituberculous therapy, achieved immune reconstitution and viral suppression and is tumor-free 2 years after tumor excision. Patient 2 died before further therapy. The immune status, presence, and appropriate therapy of co-existent systemic infection and highly active antiretroviral therapy in AIDS patients with EBV-LMS are crucial to a favorable outcome.

Epstein-Barr virus-associated adrenal smooth muscle tumors and disseminated diffuse large B-cell lymphoma in a child with common variable immunodeficiency: a case report and review of the literature

This article reports the clinical and the histological features in a 7-year-old girl affected by common variable immunodeficiency (CVID) who developed multiple Epstein-Barr virus-associated tumors, represented by bilateral adrenal smooth muscle tumors (EBV-SMT) and multifocal diffuse large B-cell lymphoma. The EBV-SMTs showed features compatible with a benign or at least a low-malignant potential neoplasm. A peculiar feature observed in both EBV-SMTs was the occurrence of numerous lymphocytes intermingled with the spindle cells, which consisted of CD3+ CD5+ T-cells, with a predominant cytotoxic CD8+ component. Interestingly, EBV status differed in the neoplasms, since the EBV-SMTs were negative for LMP1 and positive for EBER, whereas the B-cell lymphoma expressed both EBV markers. Furthermore, EBV-LMP1 deletion was positive only in the EBV-SMTs, thus indicating that these tumors were the consequence of 2 distinct, EBV-dependent transformations. Similarly, lymphocyte clonality assay also showed different clonal bands in different sites (skin and nasal cavity), suggesting the development of intratumoral mutations. Finally, the authors review all 127 previously reported EBV-SMT, with discussion of their clinical and pathological features.

AIDS-Related EBV-Associated Smooth Muscle Tumors: A Review of 64 Published Cases

The number of reported cases of smooth muscle tumor (SMT) arising in patients with AIDS has been increasing since the mid-1990s. The aim of this study is to characterize the epidemiology, clinical manifestations, pathologic features, prognosis and, management of Epstein-Barr virus-related SMT (EBV-SMT) in patients with AIDS. An English language literature search identified 53 articles including 64 reported cases of EBV-SMT. The majority of these reports involved patients who were young, severely immunosuppressed, and had multifocal tumors. The central nervous system was the most common site to be involved. Histologically, tumors had smooth muscle features and were immunoreactive for muscle markers and all but two tumors demonstrated the presence of EBV by either immunohistochemistry, in situ hybridization, and/or PCR. While mitoses and/or necrosis were used to separate leiomyoma from leiomyosarcoma, these features did not correlate with clinical outcome. Treatment included primarily resection, and less often radiotherapy, chemotherapy and highly active antiretroviral therapy (HAART). Overall, EBV-SMTs appear to have variable aggressiveness and clinical outcome and may exhibit a more favorable prognosis compared to conventional leiomyosarcoma. Tumor-related death from EBV-SMT occurred in only 4 of 51 patients.

Leiomyosarcoma in an HIV-infected adult with renal and central nervous system involvement

We describe a case of leiomyosarcoma in an HIV-infected adult with renal and central nervous system involvement and possibly the lungs.

Dermatopathological challenges in the human immunodeficiency virus and acquired immunodeficiency syndrome era

The histopathological assessment of cutaneous lesions is critical to the definitive diagnosis of many human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome-associated dermatoses, infections and tumours. Dermatopathological challenges stem mainly from the altered histopathological profile of established cutaneous entities compared with that in the HIV-unaffected population, the emergence of new diseases and the impact of therapeutic modalities on cutaneous lesions. This review focuses on some of these diagnostic dilemmas, with emphasis on the following challenges: (i) infective diagnostic pitfalls; (ii) itchy papular skin lesions; (iii) co-lesional comorbid diseases; (iv) drug-induced disease alterations; and (v) neoplastic and pseudoneoplastic proliferations. The drug-induced alterations include highly active antiretroviral therapy-associated disease modifications.

Myopericytoma in patients with AIDS: a new class of Epstein-Barr virus-associated tumor

Myopericytoma is an uncommon, benign perivascular myoid cell tumor that occurs almost exclusively in somatic soft tissues. We report 2 cases occurring in patients with acquired immunodeficiency syndrome who show unusual clinical and biologic features. One patient presented with a bronchial mass and the other developed mass lesions of the tongue, vocal cord, and brain. Histologically, oval to plump spindly tumor cells with uniform nuclei and scanty cytoplasm formed sheets or cuffs around gaping or narrow vascular spaces. Focally, these areas merged into fascicles of more elongated cells with eosinophilic cytoplasm. The tumor cells were immunoreactive for actin but not desmin, and showed uniform labeling for Epstein-Barr virus (EBV) encoded RNAs on in-situ hybridization. Both patients were alive 5 years after incomplete excision of the lesions. In conjunction with another case reported in the literature, myopericytoma occurring in acquired immunodeficiency syndrome patients exhibits several features distinct from sporadic myopericytoma: presentation in anatomic sites other than somatic soft tissues, frequent presence of multifocal disease, and association with EBV. This tumor type therefore also broadens the spectrum of neoplasms associated with EBV.

Epstein-Barr virus-associated smooth muscle tumor of the iris in a patient with transplant: a case report and review of the literature

Epstein-Barr virus infection has been linked to the development of smooth muscle tumors in immunocompromised patients with organ transplants and acquired immunodeficiency syndrome. A 52-year-old female recipient of a renal transplant presented with enlarging masses of the left iris. Incisional biopsy of the mass revealed a smooth muscle tumor of the iris. Epstein-Barr virus infection was confirmed by in situ hybridization for Epstein-Barr virus-encoded, small RNA in tumor cells. Eight months after total iridectomy the patient was free of disease. Although the prognosis and classification of Epstein-Barr virus-associated smooth muscle tumors are controversial, mortalities caused by these tumors are rare.

EBV-associated smooth muscle tumour presenting as a parapharyngeal mass--a rare presentation

The Epstein-Barr virus-associated smooth muscle tumour (EBV-SMT) is a rare entity that has only recently been recognised. Since its first description in 1993, it has been reported only in immunocompromised patients, and generally presents as one or more non-specific mass lesions which may arise almost anywhere within the body. Because of its sporadic occurrence, non-specific presenting features and frequently unusual sites of occurrence, it often presents a diagnostic challenge for the clinician. We describe an interesting patient with an EBV-SMT which masqueraded as nasopharyngeal carcinoma, presenting with serous otitis media, nasopharyngeal mass and raised Epstein-Barr virus (EBV) serology.

Posttransplant Epstein-Barr virus-associated myogenic tumors: case report and review of the literature

Epstein-Barr virus (EBV) has been implicated in the pathogenesis of different types of malignancies. While nonmelanoma skin cancers, lymphomas and Kaposi sarcomas are the most frequently reported malignancies after solid organ transplantation, EBV-associated smooth muscle tumors (EBV-SMT) after transplantation are rare and thus far only 18 cases in kidney recipients have been reported. A case of a 51-year-old kidney transplant recipient diagnosed with EBV-SMT is reported together with a review of the literature.

Gastrointestinal malignancies in HIV-infected or immunosuppressed patients: pathologic features and review of the literature

The gastrointestinal (GI) tract is a common internal organ to be involved by human immunodeficiency virus (HIV)-related malignancies. It is the second most common site for Kaposi sarcoma after skin, and the commonest visceral site, for Kaposi sarcoma in AIDS patients. GI lymphomas have been documented in approximately 25% of AIDS patients with systemic lymphomas. Moreover, GI involvement of AIDS-lymphoma has been associated with poor prognosis and short survival. Several other malignancies that occur in the GI tract are also closely related to HIV-infected or immunosuppressed individuals; these include posttransplant lymphoproliferative disorder, Epstein-Barr virus-associated smooth muscle tumors, anal precancerous lesions, and squamous cell carcinoma. As a result of active antiretroviral therapy, patients infected with HIV are living longer and are consequently at increased risk for development of cancer. Therefore, it is possible that the number of AIDS-associated malignancies will rise and the pattern of tumors may change in the future. In this paper, the clinicopathologic features of GI malignancies associated with AIDS patients are reviewed and the differential diagnosis with other mimic lesions is discussed.

Cryptococcal Inflammatory Pseudotumors

"Inflammatory pseudotumors" (IPTs) embrace a heterogeneous spectrum of reactive, infective, and neoplastic entities, that are characterized by a clinical mass composed of a histologic proliferation of spindle cells in a background of inflammatory cells and collagen fibers. Although a spectrum of microorganisms have been identified in infective IPTs, mycobacterial infective IPTs are reported most commonly. We document 5 solitary cryptococcal IPTs, in 2 males and 3 females, aged 19 to 43 years, in the soft tissues of the anterior chest wall, thigh, and arm. All were HIV-positive and had been treated for disseminated cutaneous and/or meningeal cryptococcosis with antifungal therapy, 6 to 12 months earlier. The specimens demonstrated a storiform arrangement of plump spindle cells, in addition to spindle and polygonal cells that were arranged in a haphazard manner. Background lymphocytes, plasma cells, and fibrosis were noted, in addition to scattered giant cells and focal necrosis. On high-power examination, Cryptococcus neoformans yeasts were identified within and between vacuolated spindle and polygonal cells on routine and special stains, confirming cryptococcal IPTs. Immunophenotyping of the spindle cells confirmed a mixed histiocytic and myofibroblastic lineage, with a predominance of the former. In documenting 5, hitherto unreported, pseudotumoral spindle cell reactions to C. neoformans, we not only highlight the need for intense appraisal of all IPTs for infective agents on routine and special stains and investigations, but also postulate that a complex host-fungus interaction, coupled with an exuberant, myofibroblastic response to incomplete therapy, are the pathogenetic drive for the pseudotumoral presentation.

Epstein-Barr virus-associated smooth muscle tumour mimicking bilateral vocal process granuloma

A case is presented of a 36-year-old Chinese woman with a renal transplant for end-stage renal failure due to Goodpasture's syndrome. She presented with a year's history of throat discomfort and acid regurgitation into her throat. Videolaryngoscopy revealed bilateral vocal process granuloma, presumed to be due to gastroesophageal reflux. A four-week course of high dose omeprazole was prescribed. On follow up a month later, the granulomas had enlarged, and laser excision was undertaken. Histological and immunohistochemical staining was consistent with Epstein-Barr virus-associated smooth muscle tumour. This is believed to be the first reported case in the English literature of such a tumour affecting the vocal process. The aim of this paper is to present the pathogenesis, clinical behaviour and treatment of Epstein-Barr virus-associated smooth muscle tumour, and to review the literature concerning the differential diagnosis of polypoid vocal process lesions.

Epstein-Barr Virus-Associated Smooth Muscle Tumors Are Distinctive Mesenchymal Tumors Reflecting Multiple Infection Events

Epstein-Barr virus-associated smooth muscle tumors (EBV-SMT) are rare lesions that occur in immunocompromised patients. Because they have not been fully characterized pathologically or at the molecular level, we have studied 29 tumors from 19 patients, the largest series to date. Cases coded as EBV-SMT were identified in 19 patients from consultation files and from the renal transplant database at Singapore General Hospital. EBV-SMT occurred in adults (mean age 39 years; range, 21-57 years) and predominantly affected males (12 male, 7 female). Causes of immunocompromise were renal transplantation (10), AIDS (8), and steroid therapy (1). Tumors were located in soft tissue (5), lung (5), liver (4), and miscellaneous sites (15). In 13 patients (68%), the tumors were multiple. Infection with EBV was confirmed in all cases by in situ hybridization for EBV early RNAs (EBER). EBV-SMT were typically well-differentiated smooth muscle tumors with little atypia and usually a low level of mitotic activity. Unlike classic leiomyosarcomas, they lacked significant pleomorphism but frequently displayed primitive round cell areas and prominent intratumoral T lymphocytes. No consistent relationship between histologic features and clinical outcome was noted. All expressed actin (29 of 29) and less frequently desmin (14 of 26). Multiple tumors in a given patient were clonally distinct as assessed by the long terminal repeat region of the virus, supporting the view that multifocal tumors arise from multiple infection events rather than from metastasis. Strain typing by analysis of the EBNA-3C gene confirmed the presence of EBV type 2. Two of four tumors assessed were positive for a 30-bp deletion in the LMP1 gene. EBV copy number per cell ranged greatly between patients and between tumors from the same patient. Follow-up information was available in 18 of 19 patients (mean, 25 months; range, 1-105 months). Fifteen patients were alive: 11 with disease and 4 without. Three patients died, 1 due to disease. We conclude that EBV-SMT are histologically distinct from classic soft tissue smooth muscle tumors, are not readily evaluated by means of conventional histologic criteria, and in the case of multifocal tumors are the result of multiple infection events rather than metastasis. EBV-2 can transform smooth muscle cells, independent of the presence of the LMP1 deletion associated with greater virulence.

Epstein-Barr Virus Infection-Associated Smooth-Muscle Tumors in Patients with AIDS

BACKGROUND

The aim of our study is to describe the unusual clinical manifestations of smooth-muscle tumors (SMTs) in patients with acquired immunodeficiency virus (AIDS) and to demonstrate the association between Epstein-Barr virus (EBV) infection and SMTs.

METHODS

Nine patients with AIDS and SMTs were characterized at Chulalongkorn Hospital (Bangkok, Thailand) from 2001 through 2003. Tumor tissues suitable for immunohistochemical analysis and in situ hybridization were assayed for SMTs and EBV, respectively. Plasma and serum samples were tested for EBV by real-time quantitative polymerase chain reaction and serologic analysis.

RESULTS

The study included 8 adults and 1 child (3 males and 6 females). All patients had CD4 cell counts of <200 cells/microL. By the end of the study, 3 patients had died, and 6 patients had survived. The sites of SMTs were the epidura (5 intracranial and 4 intraspinal SMTs), vocal cords (2), adrenal glands (2), abdominal wall (2), iris (1), liver (1), lung (1), orbit (1), and thigh (1). Seven patients had multicentric SMTs involving intracranial sites only (4 SMTs), extra- and intracranial sites (3), or extracranial sites only (2), which occurred either concurrently or sequentially. We found evidence of EBV infection, as determined by in situ hybridization, in all SMTs. Furthermore, EBV DNA was detectable in plasma samples from 2 patients. The results of serologic analysis were consistent with past EBV infection.

CONCLUSIONS

SMTs in patients with AIDS typically arise in multiple and very unusual sites that are not often observed in SMTs among immunocompetent individuals. Our series also suggests association between EBV infection and SMTs in patients with AIDS. The exact role of EBV in smooth-muscle oncogenesis awaits further study.

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.

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.