Kaposi sarcoma: a continuing conundrum

Kaposi's sarcoma: imaging overview

Kaposi's sarcoma (KS), a low-grade malignancy that is associated with human herpesvirus-8 (HHV-8), is a multifocal tumor that most commonly affects mucocutaneous sites. It might also involve lymph nodes and visceral organs, in particular of the respiratory and gastrointestinal tract, but it can affect every organ system. Four forms of the disease have been recognized: the classic, the endemic, the transplant-associated, and the epidemic form. The endemic form, or African KS, currently accounts for 10%-50% of all cancers in adults and up to 25% of cancers in children in certain parts of Africa. The epidemic form or acquired immune deficiency syndrome (AIDS)-associated KS is a frequent neoplasm in bisexual and homosexual men with AIDS in the United States. Even though in North America and Europe the incidence of KS in men with AIDS has decreased significantly after the introduction of highly active antiretroviral therapy (HAART), in some developing countries, the incidence of KS keeps growing. The pathophysiology, clinical manifestations, imaging findings, and more relevant differential diagnoses are reviewed.

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.

Isolated Kaposi Sarcoma in two HIV negative patients

BACKGROUND

Kaposi sarcoma (KS) is a neoplasm of the endothelial cells. It often manifests with multiple vascular nodules on the skin and other organs. It is a systemic, malignant and multifactorial disease and has a variable course. There are four types: classic, endemic, iatrogenic and HIV-associated. The primary presentation on the penis and face is uncommon and is mainly observed in HIV-positive patients. Multiple treatment modalities are used including surgery, cryotherapy, electrosurgery, laser and radiation therapy.

MAIN OBSERVATION

The authors present two cases of isolated Kaposi sarcoma in HIV negative, human herpes virus 8 (HHV-8) positive non immunocompromised patients. One case with facial KS and the other one with penile KS. Both were treated surgically with no recurrence in the following 6 months of the follow up period.

CONCLUSIONS

Kaposi sarcoma is rare in HIV negative patients and is associated with HHV-8 infection. Lesions are usually solitary and can be treated surgically. It should be included in the differential diagnoses of penile and facial lesions that are clinically suspecious and resistent to therapy.

Treatment of Disseminated Classic Type of Kaposi's Sarcoma with Paclitaxel

Classic Kaposi sarcoma (KS) is a rare human herpes virus 8-associated angioproliferative disease, and the disseminated classic type of KS in Korea is even rarer. The treatment options for classic KS vary and range from surgical excision to ionizing irradiation or chemotherapy. Recently, there have been a few reports of treating classic KS with paclitaxel, which has been used to treat AIDS-associated KS and post-transplant KS. We herein report a case of disseminated classic type KS in a 78-year-old Korean male patient who showed dramatic response after only two cycles of paclitaxel treatment.

Seroprevalence of Human herpesvirus 8 (HHV-8) and incidence of Kaposi's sarcoma in Iran

Seroepidemiological surveys show that the prevalence of human herpesvirus 8 (HHV-8) infection mostly varies in various geographical areas and reflects the local incidence of classic and endemic KS, being widespread in sub-Saharan Africa and Mediterranean countries and uncommon in the USA and Northern Europe. In the Middle East only few populations, such as Ashkenazi and Sephardic groups in Israel, have been adequately evaluated for HHV-8 seroprevalence. Among Iranian population a striking higher seroprevalence of HHV8 has been reported among haemodialysis (16.9%), renal transplant recipients (25%) and HIV (45.7%) patients compared to blood donors (2%). Kaposi's sarcoma (KS) is the rarest cancer in Iran, with an annual age-standardized incidence varying from 0.10 to 0.17 per 100,000 in males and from 0.06 to 0.08 per 100,000 in females. KS, however, is one of the most important malignancies in Iranian renal transplanted patients affecting up to 2.4% of organ recipients. The epidemiology of HHV8 and KS in Iran needs further evaluation. While the high prevalence of HHV-8 antibodies in HIV positive and haemodialysis individuals may be attributed to high-risk sexual behavior and polytransfusions, respectively, unknown determinants may be responsible for high seroprevalence of HHV8 and high incidence of KS in solid organ recipients. A global survey on HHV8 seroprevalence in Iran is mandatory to define co-factors associated with HHV8 infection and KS risk in the general Iranian population and in specific patient groups.

Non-AIDS associated Kaposi's sarcoma: clinical features and treatment outcome

Background

Kaposi's sarcoma (KS) in HIV negative patients is rare and has to be distinguished from AIDS associated KS. Two groups are at risk to develop non-AIDS related KS: elderly men mainly of Mediterranean origin and persons with iatrogenic immunosuppression.

Patients and Methods

In order to define risk-groups and major clinical features we retrospectively evaluated clinical data of all patients with non-AIDS associated KS presenting to the Department of Dermatology, University Hospital Tuebingen between 1987 and 2009. Data were extracted from the tumor registry of the Comprehensive Cancer Center Tuebingen and from patient records.

Results

20 patients with non-AIDS KS have been identified. The average age at KS onset was 66.6 years; the male-to-female-ratio was 3∶1. Most of the patients were immigrants from Mediterranean or Eastern European countries (60%). 15 cases of classic KS versus 5 cases of iatrogenic KS were observed. In 95% of the cases, KS was limited to the skin, without mucosal, lymph node or visceral manifestation. KS lesions were in all cases multiple and mostly bilateral, the most common localization was the skin of the lower extremities. Tumor control was achieved in nearly all cases by the use of local or systemic therapy. No patient died from KS.

Conclusions

Unlike KS in AIDS patients, non-AIDS associated KS is a rather localized process which rarely involves lymph nodes or organs. It is mostly seen in elderly males from Mediterranean or Eastern European countries and in most cases responsive on local or systemic therapeutic strategies.

Kaposi sarcoma and quinine: a potentially overlooked triggering factor in millions of Africans

Kaposi sarcoma (KS)-associated herpesvirus, also known as human herpesvirus 8, is necessary but not sufficient for the development of KS. Lytic reactivation of human herpesvirus 8 may be important in KS pathogenesis. KS and its causative agent, KS-associated herpesvirus, have distinctive largely unexplained geographic distributions. We note the recent "oncoweed" hypothesis of biologic plants in the environment accounting for this reactivation. We believe that quinine and its derivatives might better explain the epidemiology of KS than oncoweeds. Indeed, we propose an "oncodrug" hypothesis, specifically with regard to quinine and its derivatives, a linkage first advanced by one of us (V. R.) and associates in 1984.

Clinical challenge: cutaneous Kaposi's sarcoma of the lower extremity

Kaposi's sarcoma (KS) typically presents as multiple bilateral cutaneous patches or plaques of the lower extremities. This malignancy, however, can evolve with atypical presentation masquerading as a chronic wound. Lesions can mimic venous stasis ulcers, arterial insufficiency, vascular ulcers or chronic-infected wounds. With acquired immune deficiency syndrome (AIDS)-associated KS, lesions are even more widespread, and can affect the respiratory tract, lymph nodes, gastrointestinal tract, spleen, liver and, rarely, bone. As the initial diagnosis of KS is generally determined clinically, a high index of suspicion is necessary for all patients with a known or suspected history of HIV/AIDS. Tissue biopsy with histological analysis is essential for all wound types in this patient subset, regardless of wound presentation. The purpose of this report is to review the pathogenesis as well as the typical and atypical presentations of KS with an example of a diagnostic dilemma.

MDM2 and CDKN1A gene polymorphisms and risk of Kaposi's sarcoma in African and Caucasian patients

A single-nucleotide polymorphism in the MDM2 promoter (SNP309; rs2279744) causes elevated transcription of this major negative regulator of p53 in several cancer types. We investigated MDM2 SNP309 and CDKN1A (p21/Waf1/Cip1) codon 31 (rs1801270) polymorphisms in 86 cases of cutaneous Kaposi's sarcoma (KS) from African and Caucasian patients, and 210 healthy controls. A significant increase of the MDM2 SNP309 T/G genotype was observed among classic KS cases (odds ratio 2.38, 95% confidence interval 1.0-5.5). Frequencies of CDKN1A codon 31 genotypes were not significantly different between cases and controls. The results suggest that the MDM2 SNP309 G allele may act as a susceptibility gene for the development of classic KS in Caucasian patients.

Fatal outcome in classic Kaposi's sarcoma

First described in 1872, Kaposi's sarcoma is defined as a rare multifocal tumor that originates in the endothelial cells and presents with cutaneous and extracutaneous manifestations. The classic form is most common in elderly men and progression is slow. This tumor responds well to chemotherapy and radiotherapy. This report describes a classic case of Kaposi's sarcoma in a woman with skin and visceral manifestations in whom the disease rapidly progressed to a fatal outcome.

HIV/AIDS-associated Kaposi's sarcoma with multiple skin-mucosal disseminations following ultraviolet (puva) photochemotherapy

HIV/AIDS infection in Bulgaria has spread over about 1200 registered patients and it is supposed that the number of the undetected cases is four times higher. Kaposi's sarcoma is rarely observed in our country and no cutaneous-mucosal dissemination is reported for the time being.

AIM

The aim of the study is to present a case of disseminated Kaposi's sarcoma in a HIV/ AIDS patient who underwent Psoralen--UVA radiation treatment (PUVA) for total alopecia.

METHODS

HIV was proved through ELISA and Western blot (InnoLia HIV I/II Score). PCR method (COBAS-Amplicor HIV-1 MT, 1,5) was used to determine viral load (VL). Monitoring was realized by flow-cytometric phenotype analysis of the immune cells. Biopsy of a skin lesion was performed for histomorphological analysis. Computed axial tomography (CAT) of the visceral organs was also applied.

RESULTS

The patient's face, chest, back and upper extremities are covered by more than 50 typical for Kaposi's sarcoma skin tumors and several isolated lesions are found in the oral cavity mucosa. The histological results show dilated vascular spaces with large endothelial cells and spindle-like tumor cells in irregularly formed fascicles. Monitoring of the immune cells and the viral load before and after the application of highly active antiretroviral therapy (HAART) showed CD4+ T cell number = 0.147 x 10(9)/l and VL = 216 000 copies HIV-RNA/ml plasma when the disorder was first detected. A very good effect appeared 4 months after the HAART start: the mucous membrane lesions disappeared and the skin tumors decreased by number and dimensions. In the same time the CD4+ T cell number increased up to 0.255 x 10(9)/l and VL values decreased < 400 c/ml.

CONCLUSION

Disseminated form of Kaposi's sarcoma can be provoked by additional immunosuppressive factors like the implementation of PUVA therapy. Early initiation of HAART improves the process and prevents visceral dissemination.

A case of successful application of the photodynamic therapy for a patientwith kaposis sarcoma of the penis

The article describes a case of successful application of the photodynamic therapy for treatment of the classic type of Kaposis sarcoma in the area of the glans of a 60-year-old patient.

Thermotherapy in dermatologic infections

The use of local induced hyperthermia or thermotherapy for dermatologic infections has not been fully explored in the more recent medical literature. Herein, we discuss the rationale behind the use of thermotherapy and review reported clinical experience with its use in the management of cutaneous infections.

Human herpesvirus type 8 variants circulating in Europe, Africa and North America in classic, endemic and epidemic Kaposi's sarcoma lesions during pre-AIDS and AIDS era

Human herpesvirus-8 (HHV-8) variants have been found heterogeneously distributed among human populations living in diverse geographic regions, but their differential pathogenicity in Kaposi's sarcoma development remains controversial. In the present study, HHV-8 variant distribution has been analyzed in classic, iatrogenic, endemic as well as epidemic Kaposi's sarcoma (KS) during pre-AIDS and AIDS period (1971-2008) in countries with different KS incidence rate. DNA samples from cutaneous KS lesions of 68 patients living in Africa (n=23, Cameroon, Kenya and Uganda), Europe (n=34, Greece and Italy) and North America (n=11) have been subjected to PCR amplification of HHV-8 ORF 26, T0.7, K1 and K14.1/15, followed by direct nucleotide sequencing and phylogenetic analysis. Among the 23 African samples, the majority of HHV-8 ORF 26 variants clustered with the subtype R (n=12) and B (n=5). Conversely, the viral sequences obtained from 45 European and North European tumors belonged mainly to subtype A/C (n=36). In general, HHV-8 and K1 variant clustering paralleled that of ORF 26 and T0.7. Genotyping of the K14.1/15 loci revealed a large predominance of P subtype in all tumors. In conclusion, comparison of the HHV-8 sequences from classic or endemic versus AIDS-associated KS showed a strong linkage of the HHV-8 variants with specific populations, which has not changed during AIDS epidemic.

X-box binding protein 1 contributes to induction of the Kaposi's sarcoma-associated herpesvirus lytic cycle under hypoxic conditions

Kaposi's sarcoma-associated herpesvirus (KSHV), like other herpesviruses, has two stages to its life cycle: latency and lytic replication. KSHV is required for development of Kaposi's sarcoma, a tumor of endothelial origin, and is associated with the B-cell tumor primary effusion lymphoma (PEL) and the plasmablastic variant of multicentric Castleman's disease, all of which are characterized by predominantly latent KSHV infection. Recently, we and others have shown that the activated form of transcription factor X-box binding protein 1 (XBP-1) is a physiological trigger of KSHV lytic reactivation in PEL. Here, we show that XBP-1s transactivates the ORF50/RTA promoter though an ACGT core containing the XBP-1 response element, an element previously identified as a weakly active hypoxia response element (HRE). Hypoxia induces the KSHV lytic cycle, and active HREs that respond to hypoxia-inducible factor 1alpha are present in the ORF50/RTA promoter. Hypoxia also induces active XBP-1s, and here, we show that both transcription factors contribute to the induction of RTA expression, leading to the production of infectious KSHV under hypoxic conditions.

Kaposi's sarcoma virally encoded, G-protein-coupled receptor: a paradigm for paracrine transformation

Kaposi's sarcoma (KS) is an angioproliferative disease caused by infection with human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV). This virus encodes 84 open-reading frames (ORFs), many of which represent pirated versions of human genes. One of them, ORF74, encodes a predicted seven-span transmembrane receptor termed vGPCR that is similar to the human IL8 receptor CXCR2, which displays strong oncogenic activity in vitro and in vivo by a complex interplay of direct and autocrine/paracrine mechanisms. vGPCR has been shown to be both necessary and sufficient for the formation and progression of KS-like lesions in experimental model systems. Due to the fundamental role of vGPCR in the pathogenesis of KS, understanding the molecular mechanisms elicited by this unique chemokine receptor can be exploited to devise new strategies for KS management, as well as to gain novel insights into how KSHV subverts key physiological processes such as cell proliferation, chemotaxis, angiogenesis, and immunomodulation for its replicative advantage. Here we describe multiple techniques and strategies that have been used to study the unique properties and functions of vGPCR and its role in oncogenesis.