Herpesvirus-like DNA sequences in classic Kaposi's sarcoma and angiosarcoma in Japan

Anaplastic Kaposi's Sarcoma of the Adrenal in an HIV-negative Patient With Literature Review

Kaposi's sarcoma (KS) is a peculiar tumor of viral etiology, with the HHV8 rhadinovirus playing a fundamental role in its development. Several epidemiological categories of KS have been identified, of which the sporadic, endemic, iatrogenic, and the epidemic are the main ones. Several histologic disease morphologies have been described, such as inflammatory, angiomatous, spindle cell, mixed, and the anaplastic (sarcomatous) subtypes. The skin of the limbs is most commonly affected, but any other organ or site may be involved. Microscopically KS may enter the differential diagnosis with several different entities, and for this purpose the immunohistochemical detection of the viral latent nuclear antigen-1 (LNA-1) may be crucial. Sporadic KS is usually benign, but rarely it may be aggressive. Anaplastic histology heralds an ominous course in any clinical context. We report a case of anaplastic retroperitoneal KS, occurring in an HIV-negative adult man. This patient presented with a huge left suprarenal mass, which was totally resected, and initially diagnosed as inflammatory leiomyosarcoma, because of the monomorphic spindle cell tumor morphology. After 12 years the tumor recurred locally as an unresectable mass, which was biopsied and examined. At the time of recurrence, the histologic slides of the primary tumor were reviewed, and the previous diagnosis was changed to that of atypical KS. Histologically the recurrent tumor showed both spindle cell and epithelioid appearances. Strongly diffuse HHV8/LAN-1 immunopositivity was documented in both tumors. The final diagnosis for the entire case was anaplastic KS. Then, the patient died in a few months.

Angiosarcoma in HIV-negative patients is not associated with HHV-8

BACKGROUND:

Angiosarcoma is an aggressive, malignant neoplasm of vascular or lymphatic origin. Herpes virus 8 (HHV-8) is a member of the herpes family with a tropism for endothelial cells and it has been proven to induce vascular neoplasms, such as Kaposi's sarcoma. The role of HHV-8 in the pathogenesis of angiosarcoma has not been well defined.

OBJECTIVE:

To investigate the relationship between the presence of HHV-8 and angiosarcoma.

METHODS:

In this study, the team investigated the relationship between the presence of HHV-8, as determined by polymerase chain reaction, and angiosarcoma, using samples from patients with epidemic Kaposi's sarcoma as controls.

RESULTS:

While all control cases with epidemic Kaposi's sarcoma were positive for HHV-8, none of the angiosarcoma cases was.

CONCLUSION:

These findings support most previous studies that found no association between HHV-8 and angiosarcoma.

Human herpesvirus 8 and angiosarcoma: analysis of 40 cases and review of the literature

AIMS

To prove a possible involvement of the endotheliotropic human herpesvirus 8 (HHV-8) in the pathogenesis of angiosarcoma in samples from patients in a low HHV-8 seroprevalence area.

METHODS

A comprehensive series of angiosarcomas (n = 40) as well as positive and negative control tissues from patients with Kaposi's sarcoma, human immunodeficiency virus (HIV)-associated multicentric Castleman's disease or juvenile haemangioma, respectively, was analysed with two sensitive methods: immunohistochemical staining for the HHV-8 latency-associated nuclear antigen 1 (LANA-1); and polymerase chain reaction (PCR) for HHV-8 VP23 DNA sequences.

RESULTS

None of the angiosarcoma cases and none of the negative control samples (juvenile haemangiomas) revealed positive immunohistochemical staining with the LANA-1 antibody. In contrast, HHV-8 LANA-1 was clearly detected in all analysed cases of Kaposi's sarcoma and multicentric Castleman's disease. These results were confirmed by PCR assay at the DNA level.

CONCLUSION

In conclusion, the great majority of angiosarcomas investigated to date, including the series of 40 angiosarcomas analysed here, does not contain HHV-8 DNA sequences or protein. This argues against a relevant role of the endotheliotropic HHV-8 in the pathogenesis of angiosarcoma and, for vascular diseases, speaks in favour of a relatively restricted pathogenic role of HHV-8 to Kaposi's sarcoma and multicentric Castleman's disease.

Kaposi's sarcoma and other manifestations of human herpesvirus 8

Kaposi's sarcoma (KS) was described by Moritz Kaposi in 1872 and was known for an entire century as a rare disorder of older men usually of Eastern European, Mediterranean, and/or Jewish origin. In the early 1980s, the prevalence of KS began to increase dramatically and soon became the most common malignancy in patients with AIDS, especially those who were male homosexuals. In 1994, a new human herpesvirus (HHV) was found to be present in almost 100% of KS lesions. This virus was found to be a gammaherpesvirus, closely related to Epstein-Barr virus, and was designated HHV-8. Subsequently, HHV-8 DNA was found in almost all specimens of classic KS, endemic KS, and iatrogenic KS, as well as epidemic KS (ie, AIDS KS). It is now believed that HHV-8 is necessary, but not sufficient, to cause KS and that other factors such as immunosuppression play a major role. The use of highly active antiretroviral therapy (HAART) since 1996 has markedly reduced the prevalence of AIDS KS in western countries, but because 99% of the 40 million patients with AIDS in the world cannot afford HAART, KS is still a very common problem. Primary effusion lymphoma and multicentric Castleman's disease are also thought to be due to HHV-8. Although HHV-8 DNA has been described in a number of other cutaneous disorders, there is little evidence that HHV-8 is of etiologic significance in these diseases. The mechanism by which HHV-8 causes KS, primary effusion lymphoma, and multicentric Castleman's disease is not well understood but is thought to involve a number of molecular events, the study of which should further our understanding of viral oncology. (J Am Acad Dermatol 2002;47:641-55.)

LEARNING OBJECTIVE

At the completion of this learning activity, participants should be familiar with Kaposi's sarcoma and other manifestations of human herpesvirus 8.

Serological and immunohistochemical detection of human herpesvirus 8 in Kaposi's sarcoma after immunosuppressive therapy for bullous pemphigoid

Kaposi's sarcoma (KS) developed in an 87-year-old human immunodeficiency virus-negative woman from Hokkaido island 4 months after oral administration of prednisolone for the treatment of bullous pemphigoid (BP), and rapidly disseminated to almost the entire body within 2 months. The open reading frame (ORF) 59 and ORF73 proteins encoded by human herpesvirus 8 (HHV-8) were detected immunohistochemically in the nuclei of the tumour cells of KS. The protein coded by ORF73, latent protein, was detected in most of the nuclei of the tumour cells, but only a few tumour nuclei were positive for the ORF59 protein, a lytic protein expressed during active infection. The antibodies against both lytic and latent proteins of HHV-8 were detected retrospectively in the serum 4 months before the appearance of KS and before prednisolone therapy had been started. Immunosuppression associated with the treatment for BP possibly activated latent HHV-8 infection and induced the development of KS.

Molecular characterization of strains of Human herpesvirus 8 from Japan, Argentina and Kuwait

Current genotyping systems for Human herpesvirus 8 (HHV-8) are based on the highly variable gene encoding the K1 glycoprotein. Most strains collected worldwide cluster into two subtypes (I/A and II/C). Sequenced African strains have belonged to subtypes I/A and IV/B. Members of all three of these subtypes can have either the M or P allele at the right-hand side (RHS) of the genome. Strains obtained predominantly from aboriginal or relatively isolated populations have formed clades that branch at a distance from subtypes I/A and II/C, all being of the RHS P allele. The characterization is reported here of 16 Japanese, two Kuwaiti and five Argentine HHV-8 strains obtained from human immunodeficiency virus-infected and non-infected patients with Kaposi's sarcoma (KS), primary effusion lymphoma, multicentric Castleman's disease or renal transplants. K1 sequences of five Japanese, one Kuwaiti and two Argentine strains were identified as subtype I/A and eight Japanese, one Kuwaiti and three Argentine strains were subtype II/C. Three strains from elderly classic KS patients originally from Hokkaido, a northern Japanese island, were relatively closely related to strains of subtypes III/D and E. Consistent with previous observations, both the M and P alleles were identified at the RHS of subgroup I/A and II/C genomes; only the P allele was detected among the three Hokkaido strains. Distances among the Hokkaido strains were similar to the distance between subtypes I/A and II/C, suggesting that the Hokkaido strains may represent two distinct subtypes and that, as more strains are analysed, the currently recognized III/D subgroups will probably emerge as independent subtypes.

A case of classic Kaposi's sarcoma in a Japanese man: detection of human herpes virus 8 (HHV-8) infection by means of polymerase chain reaction and immunofluorescence assay

The recently discovered human herpes virus 8 (HHV-8) has been implicated in the pathogenesis of Kaposi's sarcoma (KS). Because classic KS in Japan is rare and the detection of HHV-8 DNA by polymerase chain reaction (PCR) has been successful only in limited cases, the frequency and role of HHV-8 infection in KS in Japan remain unclear. Herein we report a case of classic KS in a Japanese man whose HHV-8 infection was confirmed by the detection of lesional viral DNA and serum antibodies against lytic antigen.

Spontaneously regressed Kaposi's sarcoma and human herpesvirus 8 infection in a human immunodeficiency virus-negative patient

Kaposi's sarcoma occurring in a 78-year-old woman, with the absence of the human immunodeficiency virus infection, was correctly diagnosed by immunohistochemistry using anti-human herpesvirus 8 (HHV8) antibody (PA1-73N) for the first time. The patient suffered from chronic respiratory failure and was treated with a low dose of steroids for 2.5 years. After her medication dosage was increased for the exacerbation of the respiratory failure, multiple skin tumors in her feet and legs suddenly developed. Histopathologically, skin tumors were suspected as Kaposi's sarcoma at the first biopsy and reactive angiomatosis at the second biopsy. Polymerase chain reaction and immunohistochemistry, however, revealed the presence of HHV8 DNA fragment and positive staining in the majority of spindle cells in the skin tumors. Serological examination confirmed the positivity of anti-HHV8 antibodies. HHV8 infection and steroid-induced immunosuppression, as well as environmental factors played a role in the development of Kaposi's sarcoma in this patient, because she was born in Okinawa, which is a well-known endemic area of Kaposi's sarcoma in Japan. As her general condition improved, the skin lesions regressed without any specific treatment, and disappeared completely 8 months later, in which regression may be associated with evidence of numerous CD8 cell infiltration in the second biopsy tissues. No recurrence was observed during the following 6 month follow up.

Detection of human herpesvirus 8 in Korean Kaposi's sarcoma cases by polymerase chain reaction and in situ polymerase chain reaction

Several infectious agents, including herpesvirus-like particles, had been suggested as possible candidates for the development of Kaposi's sarcoma (KS), and a new herpesvirus, human herpesvirus 8 (HHV-8), was recently identified in the vast majority of KS lesions, irrespective of their association with human immunodeficiency virus (HIV) infection. However, the etiologic role of HHV-8 in KS remains controversial. We undertook this study to screen for and localize the presence of HHV-8 in KS in Korea. A total of 46 paraffin-embedded specimens were studied, including KS, hemangioproliferative disorders, and 10 non-KS lesions from HIV-positive patients. We performed nested polymerase chain reaction (PCR) and in situ PCR with HHV-8 specific primers. HHV-8 DNA sequences were detected in 8 of 11 KS specimens. All specimens of hemangioproliferative disorders, non-KS lesions from HIV-positive patients, and other skin samples were negative for HHV-8. When sequencing PCR products, the sequences were almost identical with the prototypic sequence for HHV-8. In PCR-positive tissues, in situ PCR staining of HHV-8 localized to nuclei of endothelial cells and perivascular spindle-shaped tumor cells. The results of this study suggest that HHV-8 is not widespread and has a certain causative role in the development of KS. Further studies, including serological and animal studies, will be helpful to appreciate an epidermiological link and pathogenetic mechanism between HHV-8 and KS.

Unusual cutaneous malignancies

The most commonly occurring cutaneous malignancies are basal cell and squamous cell carcinoma. There are, however, other rare malignancies that are encountered and should be included in the differential, in which both the clinical and the histological diagnosis may be difficult. Here, the clinical and histological features, management, and prognostic factors of merkel cell carcinoma, microcystic adnexal carcinoma, leiomyosarcoma, dermatofibrosarcoma protuberans, and angiosarcoma are reviewed.

Human herpes virus 8 (Kaposi's sarcoma herpesvirus)

Human herpes virus 8 (HHV-8) is a recently discovered herpesvirus related to Herpesvirus saimiri and Epstein-Barr virus (EBV). It has been assigned to the Rhadinovirus genus (gamma-2 herpesvirus) on the basis of its genomic sequence and structure. HHV-8 is the first member of this genus known to infect humans and it is now evident that it is the likely cause of Kaposi's sarcoma (KS). The virus is present in endothelial and spindle cells of KS, and in HIV disease the presence of HHV-8 in peripheral blood, and/or serum IgG antibodies to HHV-8, predicts the development of AIDS-related KS. HHV-8 can also infect CD19 + B cells and is of aetiological significance in the development of body cavity B cell lymphomas of AIDS. Of note, the translation products of viral open reading frames (ORFs) reveal HHV-8 to be a molecular pirate, capable of producing homologues of several human gene products that may result in alterations in cell cycle arrest, inhibit apoptosis and cell-mediated immune responses, and thus provide the potential for tumour production.