Kaposi's sarcoma: advances and perspectives

Treatments for AIDS/HIV-related Kaposi sarcoma: A systematic review of the literature

BACKGROUND

Treatment guidelines are not well established in AIDS-related Kaposi sarcoma (KS).

OBJECTIVE

We aim to review the evidence on efficacy of treatments for AIDS-related Kaposi sarcoma.

METHODS

We searched the Cochrane Library, PubMed, and Embase Database from date of database inception till July 2020. Randomized controlled trials reporting intervention consisting of any type of treatment compared to control/placebo to a different treatment modality or different combination of treatment/treatment doses with a diagnosis of AIDS-related KS are selected.

MAIN OUTCOMES AND MEASURES

Primary outcomes were response rates defined as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD). Secondary outcomes were cosmesis and adverse outcomes such as pain and erythema.

RESULTS

Thirteen out of 536 articles met our eligibility criteria. Three studies reported the efficacy of chemotherapy, two studies looked at different doses of radiotherapy regimes, and three studies compared different antiretroviral therapy (ART) and chemotherapy regimens. Other studies reported topical therapies such as alitretinoin gel, IM862, and bHCG injection which showed varied efficacies.

LIMITATIONS

Lack of standardization classification of disease activity and clinical outcomes and treatment modalities precluded meaningful comparison of studies.

CONCLUSION

The evidence of efficacy of any particular intervention is overall varied and there was insufficient evidence to recommend any particular intervention. We have provided an overview of treatments for KS but larger studies need to be carried out to verify the efficacy of treatment options reported in the literature.

Prevalence and Risk Factors of Kaposi’s Sarcoma-Associated Herpesvirus Infection among Han and Uygur Populations in Xinjiang, China

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi's sarcoma (KS), which is endangering human health worldwide, especially in Africa, Europe, the United States, and parts of Asia. The aim of this study was to investigate the prevalence of KSHV in Xinjiang. Three KSHV recombinant proteins (ORF65, ORF73, and K8.1) were used to detect KSHV infection. The serum samples to be tested were detected by an indirect ELISA method. The overall infection rate of KSHV in Xinjiang was 25.60%, with a higher infection rate in the Uygur population of 29.79%. After adjusting for possible confounders, Uygur (OR = 3.95, 95% CI 2.64–6.12, P < 0.001), agriculture and livestock (OR = 1.60, 95% CI 1.20–2.17, P = 0.002), age ≤ 50 years (OR = 1.50, 95% CI 1.13–2.00, P = 0.006), and predominantly meat-based diet (OR = 1.72, 95% CI 1.11–2.78, P = 0.018) were significantly associated with the odds of KSHV seropositivity correlation. Three unique sequences of KSHV were obtained in this study; genotypic analysis showed that the three unique sequences were all subtype A2.

Angiosarcoma secondary to postirradiation and chronic lymphedema: Case reports

INTRODUCTION

Angiosarcoma secondary to post-irradiation and lymphedema is rare, but it is aggressive with a poor prognosis. It is essential to understand these patients' clinical features and distinguish them from benign diseases or other malignant tumors.

PATIENT CONCERNS

Three patients who had radiotherapy for cancer treatment and chronic lymphedema admitted to the hospital with specific skin lesions at upper or lower extremities.

DIAGNOSIS

Excisional biopsies revealed prominent, highly atypical cells with a vasoformative area, composed of atypical, large epithelioid cells with vesicular nuclei, prominent nucleoli, and mitoses. Immunohistochemistry revealed diffuse expression of endothelial cell markers suggestive of angiosarcoma.

INTERVENTIONS

One patient had shoulder disarticulation with wide excision with adjuvant radiotherapy and chemotherapy and other 2 discontinued the treatment.

OUTCOMES

After the treatment, one patient was transferred to rehabilitation department for shoulder disarticulation prosthesis fitting without recurrence sign for 1 year. Two patient refused further treatment and was lost to follow-up.

CONCLUSION

In cases of patients with irratiation and chronic lymphedema, clinical findings suggestive of angiosarcoma, biopsy and imaging studies should be performed as soon as possible.

Extensive cutaneous iatrogenic Kaposi's sarcoma after bullous pemphigoid treatment with oral methylprednisolone: a rare Chinese case report

Bullous pemphigoid (BP) is an autoimmune disease that requires immunosuppressive therapy. Systemic corticosteroids are considered the standard treatment for moderate-to-severe BP. Kaposi’s sarcoma (KS) is a rare multifocal endothelial tumour that affects the skin, mucosa and viscera. As an angioproliferative disease of obscure aetiopathogenesis and histogenesis, KS is associated with human herpesvirus 8 (HHV-8). This current case report describes a rare occurrence of extensive cutaneous KS in a 60-year-old Chinese male patient after oral methylprednisolone treatment for BP with an emphasis on its pathological characterization. A total of more than 40 nodules were found on his trunk and lower limbs covering more than 20% of his body surface area. Immunohistochemical staining of biopsy samples from the lesion showed the patient was positive for HHV-8, CD31, CD34, XIIIa, ERG and Ki-67. The Epstein–Barr virus test showed the patient tested negative for immunoglobulin (Ig)A and IgM, but was positive for IgG. Immunosuppression associated with the treatment for BP may activate a latent HHV-8 infection and induce the development of KS.

Introduction of human gammaherpesvirus 8 genotypes A, B, and C into Brazil from multiple geographic regions

Variations in the open reading frame (ORF) K1 gene sequence of human gammaherpesvirus 8 (HHV-8) has led to the identification of 6 major genotypic clades (A, B, C, D, E, and F) in specimens isolated from around the world. These clades exhibit clear clustering among individuals in different ethnic groups and from different geographic regions. The human population of Brazil varies greatly in ethnicity because of multiple immigration events from Africa, Europe, Asia, and indigenous communities. However, there is scant information about the HHV-8 genotypes currently circulating in Brazil. Here, we describe HHV-8 genotypic diversity in isolates from Brazilian HIV-infected patients living with Kaposi's sarcoma (KS) by analysis of the complete ORF-K1 region. We also identified the most likely geographic origins of these different Brazilian genotypes. We extracted HHV-8 DNA (24 positive samples) from individuals with HIV/KS from the states of São Paulo and Rio de Janeiro, amplified the ORF-K1 gene using nested PCR (about 870 base pairs), performed sequencing and phylogenetic analysis, and then calculated the mean genetic distances of Brazilian sequences from sequences in other regions of the world (523 sequences analyzed). Phylogenetic analysis showed that genotypes C, A, and B were present in 45.8 %, 29.2 % and 25 % of the isolates from Brazil, respectively. These isolates grouped into separate clades, rather than a single monophyletic cluster. Mean genetic distance analyses suggested that these genotypes were introduced into the Brazil multiple times from different geographical regions. HHV-8/A isolates appear to be from Ukraine, Russia, and the Tartar ethnic group; HHV-8/B isolates appear to be from Congo and Democratic Republic of the Congo; and HHV-8/C isolates appear to be from Australia, Algeria, England, and French Guiana. These results contribute to a better understanding of the genetic diversity and origins of HHV-8 strains circulating in Brazil, and will provide a foundation for further epidemiological and evolutionary studies of HHV-8.

High-risk cutaneous malignancies and immunosuppression: Challenges for the reconstructive surgeon in the renal transplant population

Renal transplantation is the most frequently performed transplant procedure. Immunosuppressive therapies have dramatically increased survival rates in transplant recipients but are associated with an increased risk of skin cancers. Recent changes in immunosuppressive strategies have been adopted with the aim of reducing this challenging adverse effect. Despite these new strategies, cutaneous malignancies tend to be numerous, aggressive and associated with a higher risk of local and distant dissemination than in the non-transplant population. This represents a significant workload for transplant physicians, dermatologists, and head and neck and plastic surgeons. This review highlights key concepts in the pathogenesis of skin cancer in transplant patients, the impact current and evolving immunosuppressive strategies and regimens will have on the epidemiology, and the management of cutaneous malignancies in renal transplant patients, with particular focus on the implications for the plastic surgery community.

Genetic diversity of HHV8 subtypes in South Africa: A5 subtype is associated with extensive disease in AIDS-KS

Human herpes virus 8 (HHV8) is the etiological agent of all forms of Kaposi's sarcoma (KS). Six major subtypes (A-F), based on genetic variability of open reading frame (ORF)-K1, have been identified. Numerous studies point to differing tumorigenic and pathogenic properties of the HHV8 subtypes. The study objectives were to determine the HHV8 subtypes and their prevalence in a cohort of clinical and histologically confirmed KS in Cape Town, South Africa, and analyze associations between the different subtypes and clinical presentation of KS. Clinical records were prospectively reviewed to extract clinical presentation; demographic data were retrospectively collected and tissue biopsies were taken for ORF-K1 subtyping. Eighty six patients were subtyped; 81 AIDS (acquired immune deficiency syndrome)-KS and 5 African endemic-KS. Subtype A5 (42/86) and B2 (16/86) predominated. B1, B3, A1 and A4 subtypes were identified in 10/86, 9/86, 4/86 and 1/86 patients, respectively. A5 and B subtypes were found in African blacks and individuals of mixed ancestry, while subtypes A1 and A4 were found only in whites and individuals of mixed ancestry. Subtype A5 was associated with >10 KS lesions at presentation in the AIDS cohort (adjusted OR: 3.13; CI: 1.02-9.58). Subtypes A1 and A4 combined were less likely to be associated with poor risk tumor extension (P = 0.031) and A1 was associated with lower likelihood of lower limb involvement (P = 0.019). In conclusion, these results indicate that subtype A5 and B predominate in South Africa and A5 may be associated with more extensive disease.

Non-human immunodeficiency virus-related Kaposi's sarcoma of the oropharynx: a case report and review of the literature

INTRODUCTION

Kaposi's sarcoma is a malignant, slowly progressing, mesenchymal neoplasm characterized by a proliferation of connective tissue and capillaries. Clinical presentation is usually as nodules and red-purple plaques. This case report not only represents an uncommon presentation of Kaposi's sarcoma in a non-immunocompromised patient, but also supports the role of viral infection in the pathogenesis of this disease. It provides some interesting information about this rare disease, particularly in patients who are human immunodeficiency virus negative.

CASE PRESENTATION

A 48-year-old Caucasian man presented with a sensation of a foreign body in his throat, accompanied by stomatolalia. Maxillofacial and neck magnetic resonance imaging confirmed the presence of a voluminous solid mass at the base of his tongue with oropharyngeal space reduction. Histological analysis indicated that the lesion was compatible with ulcerated Kaposi's sarcoma of the oropharynx. Results of serological tests for human immunodeficiency virus infection were negative as was the result of the human herpesvirus-8 test, but the cytomegalovirus test result was positive.

CONCLUSIONS

This case is unusual because the patient had only oropharyngeal localization of disease, without evidence of immunosuppression or the typical background or risk factors suggesting the classic or endemic form of Kaposi's sarcoma. Isolated cases of Kaposi's sarcoma with oropharyngeal manifestations not associated with human immunodeficiency virus infection are rare, and only 15 cases have been reported to date. At present, its localization, microscopic and histological characteristics, and patterns of progression are the main tools used for differential diagnosis of Kaposi's sarcoma from other vascular neoplasms.

Classic Kaposi's sarcoma in Morocco: clinico-epidemiological study at the National Institute of Oncology

BACKGROUND

Classic Kaposi's sarcoma (CKS) is a rare disease likely associated with human herpes virus 8 (HHV-8) infection, and occurs predominantly in Jewish, Mediterranean and middle eastern men. There is a dearth of data in Moroccan patients with CKS regarding epidemiology, clinical characteristics and outcomes. This report examines a cohort of patients with CKS evaluated at the national institute of oncology over 11-year period.

METHODS

A retrospective analysis of patients referred to the national institute of oncology with classical Kaposi sarcoma, between January 1998 and February 2008, was performed. Reviewed information included demographics, clinical and pathological staging, death or last follow-up.

RESULTS

During the study period, 56 patients with a diagnosis of CKS have been referred to our hospital. There were 11 (19.7%) females and 45 (80.3%) males (male-to-female ratio: 4:1). Mean age at diagnosis was 61.7 ± 15 (range: 15-86 years). Nodules and/or plaques were the most frequent type of lesion. The most common location was the lower limbs, particularly the distal lower extremity (90%). In addition to skin involvement, visceral spread was evident in 9 cases. The most common visceral involvement sites were lymph nodes (44%), lung (22%), and gastrointestinal tract (22%). Associated lymphoedema was seen in 24 (42%) of the patients. There were 18 stage I patients (32.14%), 8: stage II (14.28%), 21 stage III (37.5%) and 9 stage IV (16.07%). A second primary malignancy was diagnosed in 6 cases (10.7%), none of the reticuloendothelial system. With a median follow-up of 45 months, 38 (67.8) patients are alive, of whom 25 (65.78%) patients with stable disease, five with progressive disease currently under systemic chemotherapy and 8 (21.05%) are alive and free of disease, over a mean interval of 5 years.

CONCLUSION

This is the largest reported series in our context. In Morocco, CKS exhibits some special characteristics including a disseminated skin disease at diagnosis especially in men, a more common visceral or lymph node involvement and a less frequent association with second malignancies.

Electrochemotherapy in the treatment of Kaposi sarcoma cutaneous lesions: a two-center prospective phase II trial

BACKGROUND

Electrochemotherapy (ECT) is an emerging treatment for cutaneous lesions of different tumor types. The combination of chemotherapy and electroporation enhances drug uptake into tumoral cells. However, its role in the treatment of Kaposi sarcoma (KS) has not yet been well defined, and to date, literature reports are scarce. We prospectively evaluated clinical activity and safety of ECT in KS patients.

METHODS

Twenty-three patients with histologically confirmed unresectable KS, not treatable by radiotherapy or intralesional vincristine therapy, were enrolled onto the study according to the European Standard Operating Procedures of Electrochemotherapy (ESOPE) guidelines and treated with a pulse generator.

RESULTS

A response to the first ECT session was obtained in all patients, with a complete response (CR) in 14 (60.9%) of 23 patients. A second ECT was performed in 5 (21.7%) and a third in 2, with a median interval between two sessions of 5.1 (range 2.5-25.5) months. Overall, a total of 15 patients (65%) experienced a CR. After a median follow-up of 1.5 years (range 2 months to 4.2 years), 16 patients maintained the response, 4 after repeated courses. Sustained local control of treated lesions was present in 20 of 23 patients. The overall survival rate was 74.4% at 2 years.

CONCLUSIONS

ECT represents an additional therapeutic tool for the management of KS cutaneous lesions, characterized by a definite clinical activity and long-lasting remissions. The absence of systemic side effects and the low impact on the immune system also make this treatment suitable for elderly people, even with repeated courses.

Lymphatic endothelial cells, lymphedematous lymphangiogenesis, and molecular control of edema formation

Lymphedema, defined as the abnormal accumulation of protein-rich fluid in soft tissues, results from the dysfunction of lymphatic system, an imbalance between lymph formation and its absorption into the initial lymphatics. Primary lymphedema occurs rarely on idiopathic or developmental abnormalities, especially hypoplasia or aplasia of lymphatics. Secondary lymphedema commonly develops when lymph transport is impaired due to lymphatic damage or resection of lymph nodes in surgery, infection, and radiation. Lymphatic endothelial cells (LECs) actively participate in the phenotypic consequences of a deranged lymphangiogenesis relating to tissue fluid accumulation in the pathogenesis of lymphedema. Recent insights into molecular genetic bases have shown an updated genotype-phenotype correlation between lymphangiogenesis, lymphatic function, and lymphedema. FOXC2, EphrinB2, VEGFR-3, VEGF-C, angiopoietin-2, Prox-1 and podoplanin have proved to be important factors of the genetic cascade linking to hereditary lymphedema, and embryonic and postnatal lymphatic development. FOXC2 may have a key role in regulating interactions between LECs and smooth muscle cells, and in the morphogenesis of lymphatic valves. Reduced VEGFR-3 tyrosine kinase activity and subsequent failure in transducing sufficient physiological VEGF-C/-D signals may affect LEC function and structure in the intercellular junctions and peri-lymphatic components. Identification of genetic markers in humans and animal models would facilitate the management of environmental factors influencing the expression and severity of lymphedema, and provide a basis for developing novel targeted therapies for the disease.

Kaposi sarcoma: a continuing conundrum

Kaposi sarcoma (KS) remains a challenge. Its classic or Mediterranean form tends to be benign. In transplant recipients it may be less so. As part of the AIDS pandemic, of which it was an original defining component, it may be life-threatening. It is due to human herpesvirus-8, which is necessary but not sufficient to produce the disease. KS has a low prevalence in the general population of the United States and United Kingdom, with an intermediate rate in Italy and Greece, and a high one in parts of Africa. In Italy, hot spots include its southern regions, the Po River Valley, and Sardinia, possibly related to a high density of blood-sucking insects. An important challenge is to treat KS patients without immunocompromising them. The potential of effective anti-herpes virus therapy and the use of sirolimus in transplantation recipients have added new opportunities for KS prevention.

LEARNING OBJECTIVES

At the conclusion of this learning activity, participants should be able to provide the most recent information about Kaposi sarcoma in the context in which it occurs. Its classic or Mediterranean form, its pattern in transplant recipients and others iatrogenically immunosuppressed, and its occurrence as a potentially life-threatening part of the AIDS pandemic will be stressed. Its etiology and transmission will be discussed in detail to facilitate understanding of Kaposi sarcoma and of human herpesvirus-8 infection in the general population of the United States and United Kingdom, in Italy and Greece, and in certain parts of Africa. Its therapy, including the concept of doing it without immunocompromising the patient, will be stressed. New opportunities for Kaposi sarcoma prevention will also be discussed.

HIV-associated Kaposi sarcoma: pathogenic mechanisms

Kaposi sarcoma (KS) is a multicentric angioproliferative disorder characterized by spindle cell proliferation, neo-angiogenesis, inflammation, and edema. Human herpesvirus (HHV)-8, a gamma-herpesvirus, is a critical factor, but is not alone sufficient for the initiation of KS. Other cofactors such as human immunodeficiency virus (HIV), host-derived cytokines, chemokines, and growth factors are required for the development of KS. Whether HIV-associated KS is a reactive hyperplastic inflammatory lesion or a true neoplasm is still controversial. It is likely that HIV-associated KS begins as a reactive disorder that in some cases progresses to a monoclonal, an oligoclonal, and a polyclonal neoplasm.

Kaposi's sarcoma in Nigeria

BACKGROUND

The prevalence of Kaposi's sarcoma (KS) in parts of Africa has been on the increase as a result of the human immunodeficiency virus (HIV) infection pandemic. However, there is a paucity of information for Nigeria.

OBJECTIVE

To describe the clinical and epidemiological characteristics of cutaneous KS in patients with HIV-infection in Benin City, Nigeria.

METHODS

All patients presenting to the dermatology and infectious diseases clinics of the University of Benin Teaching Hospital, or admitted to its medical wards, within the period July 2000-June 2005 were examined retrospectively in a chart review for KS. Diagnosis of HIV was based upon ELISA testing. The CD4(+) cell counts were performed using the Dyna Bead method and KS was diagnosed histologically.

RESULTS

In our survey, 31 patients, representing 0.84% of all new HIV patients seen during the study period, had cutaneous KS. There were 19 males and 12 females, giving a male to female ratio of 1.6 : 1. The mean age was 36.3 +/- 9 years; mean CD4(+) count was 127 +/- 14 cells/dl. The lower limbs (74.2%), trunk (48.4%) and the face (22.6%) were the most frequent sites affected. The lesions were solitary in three patients (9.7%) and multiple in 28 patients (90.3%).

CONCLUSION

The prevalence of HIV-related KS is increasing in Nigeria. There is an increase in the number of women being diagnosed with this form of KS, probably owing to more females having HIV disease.

Human herpesvirus 8--a novel human pathogen

In 1994, Chang and Moore reported on the latest of the gammaherpesviruses to infect humans, human herpesvirus 8 (HHV-8) [1]. This novel herpesvirus has and continues to present challenges to define its scope of involvement in human disease. In this review, aspects of HHV-8 infection are discussed, such as, the human immune response, viral pathogenesis and transmission, viral disease entities, and the virus's epidemiology with an emphasis on HHV-8 diagnostics.

Kaposi's sarcoma: An update

While there have been many important advances in the study of Kaposi's sarcoma (KS), it remains both a challenge and an enigma in many ways. Kaposi's original description of "multiple idiopathic hemorrhagic sarcoma[s]" in patients who died within 2-3 years resembles KS in AIDS more than classic KS in elderly men of Italian, Jewish, or Mediterranean lineage, in whom the disease is usually benign. KS had been evident in about one-third of those with early AIDS, often as its presenting sign, a pattern markedly reduced in recent times since the introduction of highly active anti-retroviral therapy (HAART). The most important advance has been the convincing etiologic linkage of KS with human herpesvirus 8 (HHV-8), which is necessary but not sufficient. It has a low prevalence in the general population of the USA and UK, with an intermediate rate in Italy and Greece, and a high one in Uganda. KS risk may be significantly lower in AIDS patients with a history of anti-herpes therapy. Many aspects of HHV-8, including its transmission pattern and different genospecies, are being scrutinized. The diagnosis of KS may be difficult. One should be aware of KS clinical variants, including telangiectatic, eccymotic, and keloidal KS. One must consider a number of other disorders, including bacillary angiomatosis. HHV-8 DNA sequences in dermatofibromas and other tumors should probably not be viewed as representing a marker for KS. Therapeutic options vary for KS. Intralesional and low-dose outpatient intravenous vinblastine may be valuable, as immunosuppression with KS is not a good idea if it can be avoided. Anti-herpes virus therapy may have potential for wide use, especially in preventing the development of KS in at risk populations, such as HHV-8 seropositive individuals undergoing transplantation surgery.

Molecular genetics of Kaposi's sarcoma-associated herpesvirus (human herpesvirus-8) epidemiology and pathogenesis

Kaposi's sarcoma had been recognized as unique human cancer for a century before it manifested as an AIDS-defining illness with a suspected infectious etiology. The discovery of Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus-8, in 1994 by using representational difference analysis, a subtractive method previously employed for cloning differences in human genomic DNA, was a fitting harbinger for the powerful bioinformatic approaches since employed to understand its pathogenesis in KS. Indeed, the discovery of KSHV was rapidly followed by publication of its complete sequence, which revealed that the virus had coopted a wide armamentarium of human genes; in the short time since then, the functions of many of these viral gene variants in cell growth control, signaling apoptosis, angiogenesis, and immunomodulation have been characterized. This critical literature review explores the pathogenic potential of these genes within the framework of current knowledge of the basic herpesvirology of KSHV, including the relationships between viral genotypic variation and the four clinicoepidemiologic forms of Kaposi's sarcoma, current viral detection methods and their utility, primary infection by KSHV, tissue culture and animal models of latent- and lytic-cycle gene expression and pathogenesis, and viral reactivation from latency. Recent advances in models of de novo endothelial infection, microarray analyses of the host response to infection, receptor identification, and cloning of full-length, infectious KSHV genomic DNA promise to reveal key molecular mechanisms of the candidate pathogeneic genes when expressed in the context of viral infection.

Lymphedema: an immunologically vulnerable site for development of neoplasms

Lymphedema is the result of accumulation of protein-rich interstitial fluid (lymph stasis) caused by a failure of lymph drainage in the face of a normal capillary filtration. Whether the origin is congenital or acquired from infection, radiation, trauma, or surgery, chronic lymph stasis impairs local immune surveillance by disrupting trafficking of the immunocompetent cells in the lymphedematous district and stimulates vicarious angiogenesis by promoting development of a collateral lymphatic and hematic network in the lymphedematous district. When the local mechanisms of immune surveillance begin to fail, the lymphedematous region becomes an immunologically vulnerable area, predisposed to malignancy, chiefly vascular tumors such as Stewart-Treves syndrome and Kaposi's sarcoma, because of the continual angiogenic stimulus.

AIDS-related tumors: integrating antiviral and anticancer therapy

The introduction of highly active antiretroviral therapy (HAART) has changed dramatically the landscape of HIV disease. Deaths from AIDS-related diseases have been reduced by 75% since protease inhibitor therapy and combination antiretroviral therapy came into use in late 1995. While KS is declining, the situation for non-Hodgkin's lymphoma is more complex with a reduced incidence of primary central nervous system lymphoma, but a relative stability in the number of patients developing systemic NHL. AIDS-related NHL appears not to be markedly decreased by the introduction of HAART and it is the greatest therapeutic challenge in the area of AIDS oncology. The emphasis has now shifted to cure while maintaining vigilance regarding the unique vulnerability of HIV-infected hosts. Furthermore, also for the prolongation of the survival expectancy of these patients, other non-AIDS-defining tumors, such as Hodgkin's disease, anal, head and neck, lung and testicular cancer, and melanoma have been recently reported with increased frequency in patients with HIV infection.

A case of Kaposi's sarcoma associated with pemphigoid nodularis

Pemphigoid nodularis is a rare variant of bullous pemphigoid. Bullous pemphigoid complicated by internal malignancy has been well documented. There have been only a few reported cases of bullous pemphigoid associated with Kaposi's sarcoma. We described a case of pemphigoid nodularis who later developed Kaposi's sarcoma that might be related to immunosupressive therapy, a situation that has not been reported previously.

The antiviral drug docosanol as a treatment for Kaposi's sarcoma lesions in HIV type 1-infected patients: a pilot clinical study

Docosanol inhibits a broad spectrum of lipid-enveloped viruses in vitro including HSV-1, HSV-2, VZV, CMV, HHV-6, and HIV-1. These observations led us to conduct a pilot clinical study with docosanol 10% cream as a topical treatment for Kaposi's sarcoma (KS) in HIV-1-infected patients. In this open-label study 28 cutaneous KS lesions in 10 HIV-1-infected patients were treated topically five times daily for 4 weeks with evaluation of lesion characteristics of area, edema, and color. All patients elected to enroll in an extended treatment protocol and continued to treat for up to 35 weeks. Within 28 days, 2 of 10 patients exhibited a partial response based on standardized criteria exhibiting 74 to 83% reductions in total target lesion areas. With extended treatment, a partial response was exhibited in two additional patients where total target lesion area was reduced by 52% in one patient and target lesions in another patient that had been large, swollen, and painful at study initiation were no longer visible. No patient experienced disease progression or signs of visceral disease. The average percent decrease in lesion area for all target lesions was 20% (p < 0.01). A patient's response to therapy appeared to be independent of anti-HIV regimen, HIV viral load, or previous KS treatments. These results suggest that docosanol merits further investigation as a potential topical therapy in the treatment of AIDS-associated Kaposi's sarcoma lesions.

An overview of sexually transmitted diseases. Part III. Sexually transmitted diseases in HIV-infected patients

The HIV epidemic has dramatically altered the field of sexually transmitted diseases (STDs). HIV infection is unique among sexually transmitted diseases because it can modify the clinical presentation and features of other STDs. Conversely, other STDs can affect the transmission of HIV. This review is the third part of a series that has provided a general overview of STDs. In this article, genital ulcer diseases (genital herpes, syphilis, chancroid, lymphogranuloma venereum, and granuloma inguinale), human papillomavirus infection (anogenital warts and subclinical infections), molluscum contagiosum, human herpesvirus 8 infection, viral hepatitis, and ectoparasitic infestations (scabies and pediculosis pubis) are discussed as they occur in HIV-infected hosts. Additional features as they relate to HIV-infected patients, such as epidemiology and transmission, are discussed when applicable.

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should improve their understanding of sexually transmitted diseases in the HIV-infected host.

Decreased immunoreactivity for cell-cycle regulator p27(Kip1) in Kaposi's sarcoma correlates with higher stage and extracutaneous involvement

A consistent relationship has been established between the development of Kaposi's sarcoma (KS) and human herpes virus-8 (HHV8) infection. HHV8-encoded v-cyclin, through its complexing with cyclin-dependent kinase 6, contributes to the phosphorylation and proteasome-mediated degradation of p27(Kip1). On the other hand, down-regulation of p27(Kip1) expression seems to facilitate metastatic dissemination in a variety of human neoplasms. Although the neoplastic nature of KS remains controversial, it has been repeatedly demonstrated that in some patients KS may behave as a malignant neoplasm and follow an ominous course, especially in HIV-positive patients and when associated with extracutaneous involvement. To determine whether decreased p27(Kip1) levels are also related to more aggressive behaviour in KS, it was decided to investigate p27(Kip1) immunoreactivity in KS biopsy specimens and its possible changes in relation to cutaneous versus extracutaneous involvement and HIV serological status. Forty-nine cases of KS (29 AIDS-related and 21 classical) corresponding to 30 cutaneous biopsy specimens (ten macules, seven plaques, and 13 tumours) and 19 extracutaneous biopsy specimens were immunostained to determine the expression of p27(Kip1) and the proliferation marker Ki-67 antigen. The mean percentages of p27(Kip1)-positive cells were significantly higher in biopsy specimens from skin lesions (77.8+/-21.1) than in those from extracutaneous locations (42.0+/-26.0). Amongst cutaneous lesions, p27(Kip1) expression was significantly higher in macules (83.8+/-18.5) and plaques (91.4+/-6.4) than in tumours (65.8+/-22.6). Ki-67 immunoreactivity showed no correlation with any of the variables studied. These results lend support to the hypothesis that decreased levels of p27(Kip1), which may have been brought about by HHV8 infection, play a role in KS progression through its various histopathological stages, to its eventual extracutaneous spread.

FGF4 and INT2 oncogenes are amplified and expressed in Kaposi's sarcoma

Kaposi's sarcoma (KS) is a vascular tumor, the pathogenesis of which has been suggested to include human herpesvirus 8 (HHV-8) as well as various cytokines and growth factors. Very little is known about cytogenetic and molecular genetic changes in KS. We studied DNA copy number changes in KS and found a recurrent gain at 11q13. We then analyzed the amplification and expression status of two known oncogenes, FGF4 and INT2, residing at 11q13. Comparative genomic hybridization, interphase fluorescence in situ hybridization with yeast artificial chromosome probes containing FGF4 and INT2, and immunoperoxidase immunostaining with anti-FGF4 and -INT2 antibodies were used on 12 KS samples. All samples tested were shown by polymerase chain reaction to be HHV-8 positive. A recurrent gain at 11q13 was shown by comparative genomic hybridization in 4 of 10 cases studied. Of six cases studied by interphase fluorescence in situ hybridization, four showed a 3- to 4-fold amplification with the probes containing FGF4 and INT2. Expression of FGF4 and INT2 was found in nine and three cases, respectively, of nine studied. Amplification and expression of these genes is particularly interesting in the context of oncovirus involvement, because INT2 is a homolog of mouse int2 which causes mammary carcinoma in mice when activated by integration of retrovirus mouse mammary tumor virus. This raises the question of whether HHV-8 represents an integrating oncovirus that causes amplification and activation of genomic oncogenes in humans.

Immunohistochemical detection of Bcl-2 in Kaposi's sarcoma lesions varies according to histopathologic stage, whereas expression of Bcl-x and Mcl-1 differs according to human immunodeficiency virus serologic status of patients

Expression of Bcl-2, Bcl-x, and Mcl-1 was immunohistochemically evaluated in 33 cases of Kaposi's sarcoma (KS) of the skin. Of these, classic KS (C-KS) accounted for 17 cases (10 in plaque stage and 7 in tumor stage) and acquired immunodeficiency syndrome-associated KS (AIDS-KS) accounted for 16 cases (8 in plaque stage and 8 in tumor stage). In both C-KS and AIDS-KS, Bcl-2 immunoreaction correlated with progression stage, its average score intensity being more than 2-fold in tumors than in plaques. In contrast, Bcl-x and Mcl-1 staining intensity was unrelated to progression stage but was dependent on human immunodeficiency virus infection status. Thus, whereas Bcl-x expression was stronger in C-KS cases, Mcl-1 immunostaining was more intense in AIDS-KS instances. These findings indicate that in cutaneous KS, some Bcl-2 family proteins exhibit differential expressions that are dependent on either progression stage or human immunodeficiency virus infection status.

c-Src mediates mitogenic signals and associates with cytoskeletal proteins upon vascular endothelial growth factor stimulation in Kaposi's sarcoma cells

Vascular endothelial growth factor (VEGF) appears to be a critical cytokine modulating the growth and spread of Kaposi's sarcoma (KS). Furthermore, infection with the KS herpes virus results in up-regulation of VEGF and triggering of VEGF receptor activation. The molecular mechanisms regulating such cytokine-driven proliferation of KS cells are not well characterized. We investigated the role of Src-related tyrosine kinases in VEGF-mediated signaling in model KS 38 tumor cells. VEGF stimulation specifically activated c-Src kinase activity but not that of other related Src kinases such as Lyn, Fyn, or Hck in KS cells. Pyrazolopyrimidine, a selective inhibitor of Src family tyrosine kinases, significantly blocked the VEGF-induced growth of KS cells. Further studies using mutants of c-Src kinase revealed that Src mediates mitogen-activated protein kinase activation induced by VEGF. We also observed that VEGF stimulation resulted in increased tyrosine phosphorylation of the focal adhesion components paxillin and p130cas. Furthermore, VEGF induction enhanced the complex formation between Src kinase and paxillin. Src kinase appears to play an important functional role in VEGF-induced signaling in KS cells and may act to link pathways from the VEGF receptor to mitogen-activated protein kinase and cytoskeletal components, thereby effecting tumor proliferation and migration.

Penile Kaposi's sarcoma preceded by chronic penile lymphoedema

Kaposi's sarcoma localized to the penis with striking lymphoedema is extraordinary. We report a middle-aged Haitian man who was human herpesvirus-8 seropositive, without evidence of immunosuppression or human immunodeficiency virus infection. He was first seen with Kaposi's sarcoma of 6 months duration localized to his penis, preceded by a 3-year history of chronic penile lymphoedema. His tumour regressed completely after radiotherapy. We propose that chronic lymphoedema in this patient predisposed to the development of Kaposi's sarcoma.

Kaposi's sarcoma. New treatment modalities

Over the last 20 years of experience with the AIDS epidemic, we have accumulated a great body of knowledge on Kaposi's sarcoma (KS), a major cause of morbidity and mortality in AIDS patients, especially among homosexual and bisexual men. New antiretroviral therapies, in particular the protease inhibitors, appear to be changing the clinical course of KS. Now, it is not unusual to observe a complete resolution and control of KS with the use of these new agents. As we have begun to unravel the pathogenesis of KS, new treatment modalities have merged targeting some of its pathogenic pathways. Although, chemotherapy remains the cornerstone of its treatment, in particular with the new liposomal preparations, new agents may soon change our approach to KS. Experimental therapies being evaluated in ongoing clinical trials include angiogenesis inhibitors, hormonal therapies, retinoic acid derivatives, and immune modulators such as interleukin 12. Better treatment for HIV, and new experimental therapies targeting the pathogenic mechanisms of KS allow us to envision the future treatment of KS with a certain degree of optimism.

Absence of Fas (CD95) and FasL (CD95L) immunohistochemical expression suggests Fas/FasL-mediated apoptotic signal is not relevant in cutaneous Kaposi's sarcoma lesions

It has been suggested that Fas ligand (FasL), expressed by several neoplastic cell lines and some tumors in vivo, is able to trigger the apoptotic process in activated T-lymphocytes and may constitute a key element of the immunological escape mechanisms used by many types of neoplasia. In order to evaluate the possible role of Fas-mediated apoptosis in Kaposi's sarcoma (KS), we have studied the immunocytochemical expression of Fas and FasL in biopsy specimens showing different histopathological stages of classic KS (C-KS) and AIDS-associated KS (AIDS-KS), as well as in cultured cells derived from C-KS lesions. KS biopsy tissue failed to show Fas expression in all epidemiologic forms and histopathologic stages studied, while FasL positivity was present in a small number of cells in just a few cases. Double immunostaining ruled out the lymphocytic nature of these cells, whose morphology in adjacent sections stained with hematoxylin and eosin was consistent with KS cells. In contrast, cultured KS cells exhibited strong immunocytochemical cytoplasmic expression of both Fas and FasL. These findings indicate that the Fas-FasL system does not play a major role as a trigger of apoptosis in KS cells in vivo and that the upregulation of these molecules observed in KS cells in vitro probably is the result of cell stress induced by growth in culture.

Expression of multiple matrix metalloproteinases and urokinase type plasminogen activator in cultured Kaposi sarcoma cells

Kaposi's sarcoma (KS) cells are considered to be of endothelial origin. KS lesions are characterized by hyperproliferation and an invasive phenotype. We have determined that KS cell cultures constitutively secrete multiple forms of several matrix metalloproteinases (MMPs) and an altered form of urokinase plasminogen activator (uPA) by zymogram and Western analysis of the culture media. MMPs are a family of secreted endoproteinases which degrade components of the extracellular matrix. Their enhanced expression and activity are strongly correlated with cellular processes involving tissue remodeling and invasion. The KS cells secrete increased levels of gelatinase A and B and a high molecular weight uPA in vitro when compared with non-KS endothelial or epithelial cells. Multiple forms of gelatinases A and B were observed on gelatin zymograms. Caseinolytic bands observed were confirmed by Western blot analysis to be due to stromelysin activity, whereas matrilysin was not detected by casein zymography. Western blot analysis also detected secretion of interstitial collagenase and high molecular weight uPA. Gelatinolytic activity with the mobility of gelatinase B was detected on gelatin zymograms, but not by Western analysis. This unusual constitutive expression pattern of MMPs and uPA by KS cells in vitro is characterized by elevated levels of gelatinase A, gelatinase B, interstitial collagenase, stromelysin and a high molecular weight form of uPA, and the lack of expression of matrilysin. These secreted MMPs, taken together, are capable of digesting a broad range of components of the extracellular matrix. This unusual pattern is likely to contribute to the characteristic hyperproliferative and invasive phenotype of KS lesions.

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.

Differential expression of c-Met in Kaposi's sarcoma according to progression stage and HIV infection status

Several cytokines, growth factors and the HIV transactivator Tat have been shown to be involved in the pathogenesis of Kaposi's sarcoma (KS). Hepatocyte growth factor/scatter factor (HGF) is an angiogenic cytokine that stimulates proliferation of spindle cells cultured from human KS lesions. The receptor for HGF, the c-Met protein, is expressed by endothelial cells, dermal dendrocytes and KS tumor cells both in vitro and in vivo. KS cells synthesize and secrete HGF and express the hepatocyte growth factor receptor (c-Met), thus providing an autocrine loop for tumor proliferation and neovascularization which can be enhanced by proinflammatory cytokines. We studied the immunohistochemical expression of c-Met in 40 cases of classical Kaposi's sarcoma (C-KS) and AIDS-associated cutaneous Kaposi's sarcoma (AIDS-KS), including 22 plaque stage lesions (12 AIDS-KS cases) and 18 tumor stage lesions (7 AIDS-KS cases). Statistically significant differences in the average intensity of immunohistochemical staining according to the type of lesions progression stages) and the serologic status of the patients were identified. The staining intensity of c-Met was stronger in tumors than in plaques. When only plaques were taken into consideration, the mean staining score was nearly twice as high in C-KS as in AIDS-KS.

Further confirmation of the association of human herpesvirus 8 with Kaposi's sarcoma

Recently, a new herpesvirus-like DNA sequence named Kaposi's sarcoma-associated herpesvirus (KSHV) or human herpesvirus 8 (HHV8) has been isolated from almost all cases of Kaposi's sarcoma (KS). It has not been found in most benign and malignant cutaneous hemangioproliferative disorders other than KS. To further verify the specificity of the association of this new viral DNA with KS, we examined in total 42 cases of vascular neoplasms of endothelial derivation using nested polymerase chain reaction (PCR) for the presence of a 233-bp segment of this KSHV/HHV8 on paraffin-embedded specimens. In our investigation, we added an additional step to conventional PCR protocol that uses UV light to pretreat all the PCR regeants except Taq DNA polymerase and the target DNA to eliminate the false positives caused by trace contamination. All 15 cases of typical KS, both AIDS and non-AIDS related, as well as 4 cases of atypical vascular tumors suspicious of KS, were positive for this KSHV/HHV8 DNA sequence. The remaining 23 cases of hemangioproliferative disorders other than KS, including angiosarcoma, capillary hemangioma, angiolymphoid hyperplasia with eosinophilia, epithelioid hemangioma, histiocytoid hemangioma, hemangioendothelioma, and microvenous hemangioma, were negative for HHV8. These results confirm the previous observation that KSHV/HHV8 is specific for KS within hemangioproliferative cutaneous disorders, and PCR for detection of KSHV/HHV8 might be used as an additional diagnostic tool in distinguishing KS.

AIDS-related malignancies

In the US over one million persons are currently infected with the HIV, over half a million have had AIDS, and over 300,000 have died from AIDS. Worldwide, it is estimated that more than 17 million people are currently infected with HIV, and over 1,200,000 cases of AIDS have been reported to the World Health Organization. By some estimates, up to 40% of patients with AIDS will ultimately develop some form of cancer. Non-Hodgkin's lymphoma, Kaposi's sarcoma and invasive cervical cancer have a higher incidence in persons with HIV infection and all three are AIDS-defining illnesses. In addition, several reports suggest that a number of other malignancies may occur at an increased incidence in persons with HIV infection, including squamous-cell carcinoma of the head, neck and anus, plasmacytoma, melanoma, small-cell lung cancer, basal-cell cancer, and germ-cell tumours. Clinicians should become familiar with HIV-related malignancies as their incidence is expected to further increase as more effective therapies for HIV and associated opportunistic infections allow patients to live longer in an advanced state of immunodeficiency. In the current article, we will review the clinical and therapeutic aspects of the most common AIDS-related malignancies including non-Hodgkin's and Hodgkin's lymphomas, Kaposi's sarcoma and anogenital epithelial neoplasias.

Human immunodeficiency virus tat modulates the Flk-1/KDR receptor, mitogen-activated protein kinases, and components of focal adhesion in Kaposi's sarcoma cells

Kaposi's sarcoma (KS) spindle cell growth and spread have been reported to be modulated by various cytokines as well as the human immunodeficiency virus (HIV) gene product Tat. Recently, HIV-1 Tat has been shown to act like a cytokine and bind to the Flk-1/KDR receptor for the vascular endothelial growth factor A (VEGF-A), which is expressed by KS cells. We have characterized signal transduction pathways stimulated by HIV-1 Tat upon its binding to surface receptors on KS cells. We observed that stimulation in KS 38 spindle cells resulted in tyrosine phosphorylation and activation of the Flk-1/KDR receptor. We also report that HIV-1 Tat treatment enhanced the phosphorylation and association of proteins found in focal adhesions, such as the related adhesion focal tyrosine kinase RAFTK, paxillin, and p130(cas). Further characterization revealed the activation of mitogen-activated protein kinase, c-Jun amino-terminal kinase (JNK), and Src kinase. HIV-1 Tat contains a basic domain which can interact with growth factor tyrosine kinase receptors and a classical RGD sequence which may bind to and activate the surface integrin receptors for fibronectin and vitronectin. We observed that stimulation of KS cells with basic as well as RGD sequence-containing Tat peptides resulted in enhanced phosphorylation of RAFTK and activation of MAP kinase. These studies reveal that Tat stimulation activates a number of signal transduction pathways that are associated with cell growth and migration.

Regression of Kaposi's sarcoma during therapy with HIV-1 protease inhibitors: a prospective pilot study

BACKGROUND

Early studies using HIV protease inhibitors (PI) showed regression of Kaposi's sarcoma (KS) lesions in some patients.

OBJECTIVE

Our purpose was to determine prospectively the influence of PI on HIV-related KS.

METHODS

KS lesions of nine patients with progressive cutaneous disease were prospectively evaluated clinically and by means of epiluminescence microscopy before and during PI therapy. HIV viremia and CD4 cell count were measured in parallel.

RESULTS

All patients experienced reduction or initial stabilization of KS lesions during the first 4 to 8 weeks of HIV-1 PI therapy. After a median follow-up of 7 months and according to AIDS Clinical Trials Groups criteria, six patients had a partial response, two showed stable disease, and in one noncompliant patient KS progressed, requiring chemotherapy. With epiluminescence microscopy, a reduction in skin surface alterations, lesional size, and color intensity was demonstrated in six of nine patients. PI induced a median decrease in viremia of 1.66 log and a median increase in the CD4 count of 49 cells/mm3.

CONCLUSION

In this series, HIV PI therapy reduced or stabilized KS. The efficacy of HIV-1 PI in KS may result from the improvement in cellular immunity. These results suggest the use of PI in AIDS-related KS regardless of the level of CD4 lymphocyte count and HIV viremia.